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U niversity M ic ro film s In te rn a tio n a l 300 North Zeeb Road Ann Arbor, M ichigan 48106 USA St John's Road, Tyler s Green High Wycombe. Bucks, England H P 1 0 8HR 7® 15166 s x n g h , d e v in d a r field m a c h in e r y REQUIREMENTS PRODUCTION M ICHIG AN s y s t e m FOR m o d e l in g SELECTED STATE U N IVER SITY, M icrofilm s m CASH SYSTEMS. University, International and M ICHIG AN n ,'iiH n o a u annahikjh viabh *, P H .D . # 1970 CROP FIELD MACHINERY SYSTEM MODELING AND REQUIREMENTS KJR SELECTED MICHIGAN CASH CRCP PRODUCTION SYSTEMS By Devindar Singh A DISSERTATION Subm itted t o Michigan S ta te U n iv e rs ity in p a r t i a l f u lf illm e n t o f th e requirem ents fo r th e degree o f DOCTOR OF PHILOSOPHY Department o f A g ric u ltu ra l E ngineering 1978 ABSTRACT FIELD MACHINERY SYSTEM MODELING AND REQUIREMENTS FOR SELECTED MICHIGAN CASH CROP PRODUCTION SYSTEMS By D evindar Singh A com puter model was developed t o d e sig n f i e l d m achinery system s f o r m u ltic ro p farm s. The model was u t i l i z e d t o e v a lu a te and compare m ajor cro p p ro d u ctio n s y s ta n s , t y p i c a l in so u th e rn M ichigan, o v e r a ran g e o f s iz e s w ith re s p e c t t o c o s ts and req u ire m e n ts f o r m achinery, la b o r and f u e l . The computer model d e sig n s a m achinery system b ased upon f i e l d work s p e c i f i c a ti o n s , f i e l d o p e ra tio n c a le n d a r d a te c o n s t r a i n ts , m achinery c a p a c ity r e l a t i o n s , and f i e l d work c o n d itio n s . The model s p e c i f i e s th e s i z e and number o f each m achinery component, p re p a re s a d e ta il e d week-by-week work sc h e d u le , g iv e s th e d i s t r i b u t i o n o f la b o r need s, c a lc u la te s f u e l re q u ire n e n ts f o r each o p e ra tio n , and makes d e ta il e d c o s t a n a ly s is o f th e s e le c te d m achinery s e t . The model p e rm its th r e e d i f f e r e n t u se c a te g o r ie s o f two-wheel d r iv e t r a c t o r s , each o f a unique s i z e , t o a s s u r e " n e a r - f u ll " u t i l i z a t i o n o f power. The m achinery s y s ta n d e sig n p ro ce d u re b a s i c a ll y c o n s i s t s o f a s e r i e s o f su b o p tim iz a tio n s by i t e r a t i v e s e a rc h , s u b je c t t o c o n s tr a in ts on a v a ila b le power, implement s i z e and sp eed , and com pletion o f each Devindar Singh o p e ra tio n by th e s p e c i f i e d d a te w ith th e s p e c i f i e d d e sig n p r o b a b i l i t y . The sequence o f s u b o p tim iz a tio n s i s : h a rv e s tin g c a p a c ity , la r g e t r a c t o r power, a n a l l t r a c t o r pow er, number o f t r a c t o r s f o r a l f a l f a h a rv e s tin g (w here a l f a l f a i s in c lu d e d in th e r o t a t i o n ) and number o f u n i t s o f each im plem ent. An o p e r a tio n s sc h e d u le i s p re p a re d t o d e te rm in e w h ether t h e s e l e c te d m achinery system i s s u f f i c i e n t t o s a t i s f y a l l d a te c o n s t r a i n t s a t t h e g iv e n d e s ig n p r o b a b i l i t y . I f any c o n s t r a i n t i s v i o la t e d , an a d ju stm en t i s made i n th e number o f in plem ent u n i t s o r in th e t r a c t o r power. M achinery re q u ire m e n ts (number and s i z e o f each m achinery com ponent) and c o s ts w ere d e te rm in e d f o r 29 c ro p p ro d u c tio n s y s ta n s c o n s i s t in g o f t e n c ro p r o t a t i o n s in v o lv in g c o rn , so y b ean s, f i e l d b e a n s, w heat and a l f a l f a , and t h r e e t i l l a g e s y s ta n s - m oldboard plow , c h i s e l plow and n o - t i l l . The ran g e o f farm s i z e s c o n s id e re d v a r ie d from th e maximum c ro p a re a t h a t a 2-row combine can h a rv e s t t o t h a t c o rre sp o n d in g to an 8-row c a rb in e . M u ltic ro p b a la n c e d r o t a t i o n s in c re a s e d m achinery u t i l i z a t i o n , d e c re a se d (1 ) m achinery re q u ire m e n ts on a u n i t c ro p a re a b a s i s by a s much a s h a l f , (2 ) m achinery in v estm en t by a s much a s 40 p e r c e n t, and (3 ) annual m achinery r e l a t e d c o s ts by a s much a s 30 p e rc e n t o v e r s in g le - c r o p r o t a t i o n s . T il l a g e i n t e n s i t y in flu e n c e d t r a c t o r power and f u e l re q u ire m e n ts , b u t t h e e f f e c t on m achinery in v estm en t and m achinery r e l a t e d c o s ts was g e n e r a lly l e s s th a n 15 p e rc e n t f o r m u ltic ro p r o t a t i o n s . T h is was b ecau se d i f f e r e n t c ro p s w ere r a i s e d a t th e red u ced t i l l a g e i n t e n s i t y u s in g d i f f e r e n t t i l l a g e system s and, t h e r e f o r e , more im plem ents w ere r e q u ir e d . O th er c o n c lu s io n s frcm th e stu d y in c lu d e d t h e fo llo w in g : Devindar Singh As farm s i z e in c r e a s e s , an n u al m achinery r e l a t e d c o s ts d e c re a s e a t a d e c re a s in g r a t e . Maximum re d u c tio n o c c u rs when faim s i z e i s in c re a s e d f r a n th e maximum a re a t h a t a 2-row c a rb in e can h a rv e s t t o t h a t c o rre sp o n d in g t o a 4-row combine. The ra u ltic ro p r o t a t i o n s have a more even d i s t r i b u t i o n o f la b o r d u rin g th e y e a r compared t o s in g le - c r o p r o t a t i o n s . However, t h e an n u al la b o r re q u ire m e n ts p e r u n i t a re a a r e n o t c o n s id e ra b ly a f f e c t e d by t h e c ro p r o t a t i o n . F or r o t a t i o n s in v o lv in g a l f a l f a , th e la b o r re q u ire m e n ts a r e v e ry h ig h d u rin g th r e e 2-week h a rv e s tin g se a so n s o f a l f a l f a . F u e l re q u ire m e n ts d e c re a s e w ith a d e c re a s e in t i l l a g e i n t e n s i t y f o r e v e ry c ro p r o t a t i o n . But th e v a r i a ti o n in f u e l re q u ire m e n ts among r o t a t i o n s i s g e n e r a lly l e s s th a n 25 p e r c e n t. Approved by: M ajor P ro f e s s o r D epartm ent Q iaiim an AOOSICWLEDCMENTS The a u th o r w ishes t o e x p re ss h i s s in c e r e g r a t i t u d e t o t h e fo llo w in g D r. J . B. Holtraan, th e a u t h o r 's m ajor p r o f e s s o r and c o m n itte e chairm an f o r th e m ajor p a r t o f t h e s tu d y , f o r p ro v id in g c o n tin u in g encouragem ent and g u id an ce w ith g r e a t p a tie n c e . D r. Thomas H. B u rk h ard t, th e a u th o r ’s c u r r e n t m ajo r p r o f e s s o r , f o r h i s h e lp in p re p a rin g t h i s m a n u sc rip t. D r. R. E. Lucas who se rv ed on th e a u t h o r 's g u id an ce c o n m itte e f o r two y e a rs , f o r h i s h e lp in p re p a rin g f i e l d work d a ta . D r. George E. Merva, Dr. L a rry J . Obnnor, and D r. Lynn S. R obertson who a ls o se rv e d on t h e a u t h o r 's g u id an ce c o n m itte e , f o r t h e i r h e lp f u l s u g g e s tio n s and c o n tin u e d i n t e r e s t . Mr. Dwight F. Kampe f o r h i s many h e lp f u l s u g g e s tio n s on m achinery d a ta . N a tio n a l S cien ce Foundation and M ichigan A g r ic u ltu r a l E xperim ent S t a ti o n f o r p ro v id in g f i n a n c ia l s u p p o rt f o r t h e s tu d y . TABLE OF CONTENTS Page LIST OF T A B L E S ......................................................................................................... v i LIST OF FIG U R E S......................................................................................................... x i LIST OF ACRCNYMS....................................................................................................... x i i C hapter 1. IN T R C D U C T IC N ................................................................................................................................ 1 .................................... 4 1.1 S e le c tio n o f A p p ro p riate Approach 1 .2 O b je c tiv e s o f th e S t u d y ........................................................4 1 .3 S y stan C o n s tra in ts and D e sira b le Model C h a r a c t e r i s t i c s ........................................................................... 5 2. REVIEW OF LITERATURE....................................................................................7 2 .1 2 .2 2 .3 Machine P r o d u c t i v i t i e s ........................................................7 ....................................................9 S u ita b le F ie ld Work Days S e le c tio n C r i t e r i o n .......................................................... 14 2 .3 .1 2 .3 .2 2 .3 .3 M achinery c o s ts ....................................... 15 Labor c o s t s .........................................................................16 T im elin ess c o s t s ................................................................ 16 2 .4 Machinery System D esign P r o c e d u r e s ......................................... 17 3. SYSTEM MODEL.................................................................................................. 21 3 .1 Input D a t a ...................................................................22 3 .1 .1 3 .1 .2 3 .1 .3 3 .1 .4 F ie ld work s p e c i f i c a t i o n s ............................................... 25 C alendar d a te s p e c if ic a tio n s f o r f i e l d work . 25 la b o r p o lic y s p e c i f i c a t i o n s .......................................26 Mean and s ta n d a rd d e v ia tio n o f f r a c tio n of s u i t a b l e d a y s ................................................................ 28 iii Chapter Page 3 .2 3 .3 3 .4 3 .5 3.6 3 .7 3 .8 H a rv e ste r S i z e .................................................................. 29 T ra c to r S i z e ........................................................................... 31 A v a ila b le F ie ld Work T i m e ...................................... 36 R equired F ie ld Work T im e ................................................. 38 Methodology f o r D eterm ining T ra c to r and Combine S i z e .................................................................................... 41 Inplem ent S iz e and N u m b e r ..................................................... 45 O p eratio n s S c h e d u l e ...................................................................... 45 3 .8 .1 3 .8 .2 3 .8 .3 3 .8 .4 3 .9 3.10 3.11 57 L a b o r .................................................................................... F u e l ............................................................................................. 58 Cost A n a l y s i s ...............................................................................60 3 .1 1 .1 3 .1 1 .2 4. 5. Scheduling o f non t i l l a g e o p e ra tio n s . . 52 Scheduling of t i l l a g e o p e ra tio n s . . . 53 Equipment a s s i g n m e n t ......................................................54 A djustm ents made, i f s e le c te d m achinery s e t was inad eq u ate f o r a r e a l i s t i c s c h e d u l e ........................................................... 55 L i s t p r ic e s o f m a c h i n e s .................................. Machinery c o s t s ................................................... 60 62 IMPLEMENTATION OF THE M O D E L ................................................... 65 4 .1 4 .2 C o m p a r is o n s ........................................................... T im elin ess C o s t s .................................................................... 67 68 R E S U L T S ............................................................................................. 70 5.1 70 E ffe c t o f T illa g e I n te n s ity 5 .1 .1 5 .1 .2 5 .1 .3 5 .1 .4 5 .1 .5 5 .1 .6 5 .1 .7 5 .1 .8 5 .1 .9 5 .1 .1 0 5 .2 .......................................... Continuous corn (C C) cro p r o t a t io n . . Continuous soybeans (S S) cro p r o ta tio n . Com -soybean (C S) crop r o t a t io n . . . C b m -fie ld bean (C IB ) cro p r o t a t io n . . C om -com -soybean-w heat (C C S W) crop r o t a t i o n ........................................................... O o m -c o rn -fie ld bean-w heat (C C IB W) cro p r o t a t i o n ................................................... C o r n - w b e a t- a lf a lf a - a lf a lf a (C W A A) crop r o t a t i o n ........................................................... C o m -s o y b e a n -w h e a t-a lfa lfa -a lfa lfa (C S W A A) cro p r o t a t io n . . . . C o ra -c o m -s o y b e a n -w h e a t-a lfa lfa -a lfa lfa (C C S W A A) crop r o t a t io n . . . . C o m -c o m -fie ld b e a n - w h e a t- a lf a lf a - a lf a lf a (C C IB W A A) cro p r o t a t io n . . . 72 75 75 80 80 85 85 90 93 96 E ffe c t o f Crop R o t a t i o n .............................................................. 96 iv Chapter Page 5 .3 M achinery Requirem ents and C o s t s .......................................... 114 5 .3 .1 5 .3 .2 5 .3 .3 5 .3 .4 5 .4 5 .5 5 .6 T illa g e t r a c t o r pcwer re q u ire m e n ts . . . 114 H a rv estin g m a c h i n e r y ...................................................117 M achinery i n v e s t m e n t ...................................................120 T o ta l annaul m achinery r e l a t e d c o s t s . . 122 F ie ld Labor R e q u i r e m e n t s ........................................................... 124 F u e l R e q u i r e m e n t s ............................................................................ 128 S e n s i t i v i t y A n aly sis ............................................................ 130 5 .6 .1 5 .6 .2 5 .6 .3 5 .6 .4 E f f e c t o f d e sig n p r o b a b i l it y . . . . E f f e c t o f f i e l d w orking ho u rs p e r day . . E f f e c t o f i d li n g t i l l a g e t r a c t o r s d u rin g h a rv e s t .................................................... S e n s i t iv i t y t e s t o f m achinery c o s t f a c t o r s . 130 133 133 137 6. CONCLUSIONS.......................................................................................................139 7. SUGGESTIONS FOR FURTHER S T U D Y ............................................................ 144 APPENDICES A. INPUT D A T A ....................................................................................................... 146 B. PROCEDURE FOR CALCULATING MEDIAN PLANTING, HARVESTING D A T E S .....................................................................................161 C. FIELD MACHINERY REQUIREMENTS FOR THE SELECTED MICHIGAN CASH CHOP PRODUCTION SYSTEJE.......................................... 164 LIST OF REFERENCES..................................................................................................... 171 v LIST CfF TABLES F i e ld Work In p u t D a ta f o r t h e E xanple Farm . 27 F ie ld M achinery S e t S e le c te d and Annual Machine Use f o r th e E xanple F a r m ..................................................... 46 O p e ra tio n s S chedule f o r t h e Weeks o f A p ril 24 and May 1 f o r t h e E xanple F a r m ................................... 49 Machine Schedule f o r t h e Weeks o f A p ril 24 and May 1 f o r th e E xanple F a r m ................................... 50 Sunmary o f O p e ra tio n s S ch ed u le f o r t h e E xanple Farm ( h e c ta r e s com pleted o f each o p e ra tio n in e ac h w e e k ) ...................................................................... 51 Median C a rp le tio n D a tes f o r H a rv e s tin g and P la n tin g f o r t h e E xanple Farm ( a t 50 p e rc e n t p ro b a b ility le v e l) ..................................................... 52 F uel R equirem ents f o r F i e l d O p e ra tio n s o f t h e Exanple F a r m ...................................................................... 61 M achinery C o sts f o r t h e E xanple Farm 64 Average Annual M achinery R e la te d C o sts f o r t h e E xanple F a r m ...................................................................... 64 D e s c rip tio n o f t h e S e le c te d C ropping System s 66 E f f e c t o f T i l l a g e I n t e n s i t y on S iz e , Use, and C o sts o f F i e ld M achinery f o r C C R o ta tio n 73 Median C om pletion D a te s f o r P la n tin g and H a rv e stin g in C C R o ta tio n .............................................................. 74 E f f e c t o f T il l a g e I n t e n s i t y an S iz e , U se, and C o sts o f F i e ld M achinery f o r S S R o ta tio n 76 Median O orrpletion D a tes f o r P la n tin g and H a rv e stin g in S S R o ta tio n .............................................................. 77 vi E f f e c t o f T il l a g e I n t e n s i t y on S iz e , Use, and C o sts o f F i e ld M achinery f o r C S R o ta tio n . . . . Median C om pletion D a tes f o r P la n tin g and H a rv e stin g i n C S R o t a t i o n ...................................................................... 79 E f f e c t o f T il l a g e I n t e n s i t y on S iz e , Use, and C o sts o f F i e ld M achinery f o r C IB R o ta tio n . . . . 81 Median C orepletion D a te s f o r P la n tin g and H a rv e s tin g in C FB R o ta tio n ............................................................................... 82 E f f e c t o f T il l a g e I n t e n s i t y on S iz e , U se, and C o sts o f F i e ld M achinery f o r C C S W R o ta tio n 83 Median C om pletion D a tes f o r P la n tin g and H a rv e s tin g in C C S W R o ta tio n ............................................................. 84 E f f e c t o f T il l a g e I n t e n s i t y on S iz e , U se, and C o sts o f F i e ld M achinery f o r C C FB W R o ta tio n . 86 Median C orepletion D a te s f o r P la n tin g and H a rv e s tin g in C C FB W R o t a t i o n ............................................................. 87 E f f e c t o f T il l a g e I n t e n s i t y on S iz e , U se, and C o sts o f F i e ld M achinery f o r C W A A R o ta tio n 88 Median C c c p le t ion D a te s o f P la n tin g and H a rv e s tin g in C W A A R o t a t i o n ............................................................. 89 E f f e c t o f T il l a g e I n t e n s i t y on S iz e , Use, and C o sts o f F i e ld M achinery f o r C S W A A R o ta tio n . 91 Median C orepletion D a tes o f P la n tin g and H a rv e s tin g in C S W A A R o ta tio n .................................................... 92 E f f e c t o f T i l l a g e I n t e n s i t y on S iz e , Use, and C o sts o f F i e ld M achinery f o r C C S W A A R o ta tio n 94 Median C om pletion D a te s o f P la n tin g and H a rv e s tin g in C C S W A A R o t a t i o n .................................................... 95 E f f e c t o f T i l l a g e I n t e n s i t y on S iz e , U se, and C o sts o f F i e ld M achinery f o r C C IB W A A R o t a t i o n ........................................................................................ 97 Median C om pletion D a te s o f P la n tin g and H a rv e s tin g in C C IB W A A R o t a t i o n .................................................... 98 v ii T able Page 5.11A E f f e c t o f Crop R o ta tio n on S i z e , Use, and C o sts o f F i e ld M achinery a t t h e HLTI f o r th o s e R o ta tio n s in w hich Corn i s a Dominant C r o p ................................................ 100 5.11B Median C c n p le tio n D a te s f o r P l a n ti n g and H a rv e s tin g a t t h e HLTI f o r th o s e i n w hich Corn i s a Dominant C r o p ..............................................................................................................101 5.12A E f f e c t o f Crop R o ta tio n on S iz e , U se, and C o sts o f F i e l d M achinery a t th e MLTI f o r th o s e R o ta tio n s in w hich Com i s a Dominant C r o p .................................................102 5.12B Median C om pletion D a te s f o r P l a n ti n g and H a rv e s tin g a t t h e MLTI f o r th o s e R o ta tio n s in w hich Corn i s a Dominant C r o p ..................................................................................103 5.13A E f f e c t o f Crop R o ta tio n on S iz e , U se, and C o sts o f F i e ld M achinery a t th e LLTI f o r th o s e R o ta tio n s i n w hich Corn i s a Dominant C r o p ................................................... 104 5.13B Median C om pletion D a te s f o r P la n tin g and H a r v e s tin g a t t h e LLTI f o r th o s e R o ta tio n s i n w hich Com i s a Dominant C r o p .................................................................................. 105 5.14A E f f e c t o f Crop R o ta tio n on S iz e , U se, and C o sts o f F i e ld M achinery a t t h e HLTI f o r th o s e R o ta tio n s i n w hich Corn i s n o t a Dominant C r o p ........................................... 107 5.14B Median C o u p let io n D a te s f o r P la n tin g and H a rv e s tin g a t t h e HLTI f o r th o s e R o ta tio n s i n w hich Cora i s n o t a Dominant C r o p .......................................................................... 108 5.15A E f f e c t o f Crop R o ta tio n on S iz e , U se, and C o sts o f F i e l d M achinery a t t h e MLTI f o r th o s e R o ta tio n s i n w hich Corn i s n o t a Dom inant Crop . . . 109 5.15B Median C om pletion D a te s f o r P la n tin g and H a rv e s tin g a t t h e MLTI f o r th o s e R o ta tio n s i n w hich Com i s n o t a Dominant C r o p .......................................................................... 110 5.16A E f f e c t o f Crop R o ta tio n on S iz e , U se, and C o s ts o f F i e l d M achinery a t t h e LLTI f o r th o s e R o ta tio n s i n w hich Corn i s n o t a Dominant C r o p .....................................I l l 5.16B Median C cm p leticn D a te s f o r P l a n ti n g and H a rv e s tin g a t t h e LLTI f o r th o s e R o ta tio n s i n w hich Corn is not a Demin a n t C r o p ...........................................................................112 v iii Table Page 5.17 H a rv estin g C o sts ($ /h a ) a s A ffected by Crop R o tatio n and Cbnibine S i z e ..............................................................119 5.18 Labor Requirem ents (h /h a ) a s A ffected by Crop R o ta tio n and T illa g e I n t e n s i t y ......................................................125 5.19 Labor (man-week) D is tr ib u tio n d u rin g an Average (50 p e rc e n t p r o b a b ility l e v e l) Year a t Three D if f e r e n t L ev els o f T illa g e I n te n s ity .................................. 126 5.20 5.21A Fuel Requirem ents ( l i t r e s / b a ) o f th e Crops . . . . E ffe c t o f D esign P r o b a b ility on S iz e , Use, and C o sts o f F ie ld Machinery f o r C C S ! R o tatio n a t th e HLTI . 128 . 131 5.21B Median Ccmpletion D ates f o r P la n tin g and H arv estin g a t 70 , 80, and 90 P e rc e n t D esign P ro b a b ility L evels f o r C C S W R o tatio n a t th e H L T I ............................................. 132 5.22 E ffe c t o f F ie ld Working Hours p e r Day on S iz e , Use, and C o sts o f F ie ld Machinery f o r C C S W R o ta tio n a t th e H L T I ...................................................................... 134 5.2 3 E ffe c t o f I d lin g T illa g e T ra c to rs d u rin g H arvest on S iz e , Use, and C o sts o f F ie ld Machinery f o r C C S W R o tatio n a t th e H L T I ......................................................136 A .l Assumed F ie ld O p eratio n s and C alendar D ate C o n s t r a i n t s ................................................................................................ 146 A.2A F ie ld Working Hours p e r Day Assumed f o r V arious F ie ld O p e r a t i o n s ............................................................................... 148 A.2B Mean and S tandard D ev iatio n o f F ra c tio n o f C alendar Days S u ita b le f o r Non H a rv estin g F ie ld O perations . . 149 A.2C Mean and S tandard D e v ia tio n o f S u ita b le Work Days f o r H a rv estin g O p e r a t i o n s .............................................................. 151 A. 3A Assured P r o d u c tiv ity D ata f o r S e lf-P ro p e lle d Combines . A.3B Assured P ro d u c tiv ity D ata f o r T ra c to r Powered F ie ld M a c h i n e s ........................................................................................153 A.4A A ssured S iz e and P r ic e D ata f o r T ra c to r Powered F ie l d M a c h i n e s ........................................................................................155 A.4B T ra c to r Power and P r ic e D ata used f o r Developing R egression E quation 6 .......................................................................156 . 152 Table Page A.4C C arb in e P r i c e D a t a ....................................................................................158 A.4D Com Head P r i c e D ata A.4E G rain Head P r i c e D a t a ...........................................................................159 A.4F P r ic e D ata f o r P ic k up Head and A ttachm ents f o r F ie ld B e a n s ............................................................................................. 159 A. 5 Assarted M achinery C ost F a c t o r s ............................................................160 C .l F ie ld M achinery R equirem ents f o r th e S e le c te d M ichigan Cash Grcp P ro d u c tio n S y s t e m s ............................................................ 164 ...........................................................................158 x LIST OF FIGURES F ig u re 3 .1 Page S i n p l i f i e d G eneral Flow Diagram f o r M achinery System D e s i g n ............................................................................................... 23 3 .2 Flew Diagram f a r Combine S iz e S e le c tio n 30 3 .3 Flow Diagram f o r E stim a tin g S iz e and Nunfoer o f T illa g e T r a c t o r s ............................................................................................... 32 S i n p l i f i e d Flow Diagram f o r E s tim a tin g S iz e and Number o f U t i l i t y T r a c t o r s ..................................................................... 33 S i n p l i f i e d Flow Diagram f o r S e le c tin g Number o f A l f a l f a T r a c t o r s ............................................................................................... 35 3 .6 S i n p l i f i e d Flow Diagram f o r S u b ro u tin e P0WHUNT . 42 3 .7 Labor D is tr ib u tio n a t tb e E xanple Farm f o r an Average Y e a r ....................................................................................................... 3 .4 3 .5 . . . . . . 59 5 .1 E f fe c t o f T il l a g e I n t e n s it y L evel and Crop R o ta tio n on T illa g e T r a c to r Power R e q u i r e m e n t s ............................................ 115 5 .2 E f fe c t o f C ocbine S iz e and Crop R o ta tio n on th e Maximum C ropland A rea t h a t a Combine can H arvest in one S e a s o n ....................................................................................... 118 5 .3 E f fe c t o f T illa g e I n t e n s it y and Crop R o ta tio n on I n i t i a l M achinery Investm ent f o r th e Maximum Farm S iz e s t h a t can b e H a rv ested by a 4-Rcw Combine . . 121 5 .4 E f f e c t o f T illa g e I n t e n s it y L evel and Crop R o ta tio n on T o ta l Annual F ie ld M achinery R e la te d C o sts f o r th e Maxi mm Farm S iz e s t h a t can be H a rv e ste d by a 4-Row C o m b i n e ....................................................................................... 123 5 .5 E f fe c t o f T illa g e I n t e n s it y L evel and Crop flo ta tio n on F u e l R e q u ire m e n ts .............................................................................. 129 5 .6 E f fe c t o f M achinery Cost F a c to rs on Annual C o sts f o r a 446 H e cta re C C S W Farm a t th e HLTI . . . . xi 138 LIST OF ACRONYMS CC C ontinuous c o m c ro p r o t a t i o n S S C ontinuous soybeans c ro p r o t a t i o n C S C om -soybean c ro p r o t a t i o n C FB C o r n - f ie ld bean cro p r o t a t i o n C C S lf C o m -co m -so y b ean -w h eat c ro p r o t a t i o n C C FB W O o m - c o r n - f ie ld bean-w heat c ro p r o t a t i o n C IA A O o r n - w h e a t- a lf a lf a - a l f a l f a c ro p r o t a t i o n C S WA A O o m - s o y b e a n - w h e a t- a lf a lf a - a lf a f a cro p r o t a t i o n C C S WA A C o m - c o r a - s o y b e a n - w h e a t- a lf a lf a - a lf a lf a c ro p r o t a t i o n C C FB W A A C o r n - c o r n - f ie ld b e a n - w h e a t - a l f a l f a - a l f a l f a c ro p ro ta tio n MBTS M oldboard plow t i l l a g e system CETTS C h is e l plow t i l l a g e system NTTS N o - t i l l t i l l a g e system HLTI H ip e s t le v e l o f t i l l a g e in te n s ity MLTI Medium l e v e l o f t i l l a g e i n t e n s i t y LLTI Lowest l e v e l o f t i l l a g e i n t e n s i t y TMRC T o ta l annual m achinery r e l a t e d c o s t s p e r h e c ta r e tm t I n i t i a l m achinery in v estm en t p e r h e c ta r e IWH/D F i e l d w orking h o u rs/d a y 1. INTRCDUCTICN S e v e ra l r e c e n t s t u d i e s have r a i s e d q u e s tio n s a b o u t d e c lin in g r e s o u rc e p r o d u c t i v i t i e s ( o u tp u t p e r u n i t o f r e s o u r c e in p u t) o r d e c lin in g r a t e s o f in c r e a s e in r e s o u r c e p r o d u c t i v it y in a g r i c u l t u r e (C o n m ittee on A g r ic u ltu r a l P ro d u c tio n E f f ic ie n c y , 1975; H e ic h e l, 1973; P a v e li s , 1973; and P im en te l e t a l . , 1973). E nergy, la n d , la b o r , c a p i t a l , a s w e ll a s o t h e r r e s o u rc e p r o d u c t i v i t i e s hav e been a d d re s s e d . In many i n s t a n c e s , te c h n o lo g ic a l a d ju s tm e n ts have c a u se d a g r i c u l t u r a l r e s o u r c e p r o d u c t i v it y chan g es and th e s e a d ju s tm e n ts sim p ly r e f l e c t t h e econom ic ( a s p e rc e iv e d by d e c is io n ­ m aker) s u b s t i t u t i o n o f one s e t o f r e s o u r c e s f o r a n o th e r . The economic f o r c e s f o r a d ju s tm e n ts a r e t h e i n te g r a t e d r e s u l t o f p h y s ic a l law s g o v e rn in g t h e p ro d u c tio n p r o c e s s e s , c o n s t r a i n t s upon t h e p r o c e s s e s , and t h e r e l a t i v e p r i c e s o f r e s o u r c e s (Holtm an and C onnor, 1976). T h is s tu d y i s co n ce rn e d w ith t h e a n a l y s i s and a sse ssm e n t o f th e s e r e l a t i o n s h i p s f o r f i e l d m ach in ery , l a b o r and f o s s i l f u e l in t h e p ro d u c tio n o f c e r t a i n m ajo r M ichigan f i e l d c ro p s . F i e ld c ro p s a r e a m ajor a g r i c u l t u r a l p ro d u c t o f M ichigan; 2 4 .5 p e rc e n t o f M ichigan farm s w ith s a l e s o f $2500 and o v e r w ere c l a s s i f i e d a s c a sh g r a in farm s i n 1969 Census o f A g r ic u ltu r e (Volume 1, p a r t 13, s e c tio n 1 ) . They a r e t h e second m ost cannon ty p e o f farm s i n M ichigan a f t e r d a ir y farm s (2 8 .5 p e r c e n t ) . C om , so y b ean s, f i e l d b e a n s , w heat and o a t s a r e t h e main cash c ro p s o f M ichigan. S i x t y - t h r e e p e rc e n t o f t h e c a sh g r a in farm s w ere grow ing c o m , 4 4 .7 p e rc e n t so y b e an s, 48 p e r c e n t f i e l d b e an s, 1 2 77 p e rc e n t wheat and 40.6 p e rc en t o a ts , in 1969. an im portant crop in M ichigan. A lf a lf a hay i s a lso About h a lf of a l l M ichigan farm s were growing a l f a l f a hay in 1969. F ie ld m achinery c o s ts a re a m ajor component o f th e t o t a l farm b u d g et. A Michigan stu d y (Holtman e t a l , 1976) e stim a te d t h a t f i e l d m achinery accounts f o r 24 p e rc e n t o f annual c o s ts and 21 p e rc e n t of c a p i t a l req u irem en ts in th e p ro d u ctio n o f cro p s on a d a iry farm . F u rth e r­ more extrem e v a r ia tio n s e x is t among farm s due t o cropping p r a c tic e s and management. A P ennsylvania e x te n sio n p u b lic a tio n (W aters and Daum, undated) showed t h a t m achinery c o s ts f o r corn p ro d u c tio n in 1969 v a rie d from $35 t o $116 p e r h e c ta re . F ie ld m achinery p ro d u c tiv ity p e r u n it of c ro p lan d a re a can be s i g n i f ic a n t l y in c re a se d e i t h e r by in c re a s in g m achinery u t i l i z a t i o n o r by red u c in g th e i n te n s i t y o f t i l l a g e fo r a p a r t i c u l a r cro p . Machinery u t i l i z a t i o n can be in c re a s e d by u sin g a crop r o t a t io n t h a t d i s t r ib u t e s work more evenly o v e r th e cropping y e ar. The crop r o t a t io n , i . e . th e n a tu re o f f i e l d work d i s t r ib u t i o n would s i g n i f ic a n t l y in flu e n c e peak la b o r req u ire m e n ts. req u irem en ts may a ls o be a ffe c te d by th e crop r o t a t io n . The t o t a l la b o r Reduction in th e t i l l a g e i n te n s i t y would reduce o p e ra to r la b o r re q u ire d f o r f i e l d work. F o s s il fu e l req u irem en ts would d ecrease w ith a d e c re a se in t i l l a g e i n t e n s i t y b u t would rem ain u n a ffe c te d by th e n a tu re o f f i e l d work d i s t r ib u t i o n over th e cro p p in g y e a r. F o s s il fu e l req u irem en ts may a ls o change w ith a change in th e cro p r o t a t io n . The design c o n d itio n s on f i e l d machinery sy s ta n req u irem en ts axe e x tra o rd in a ry in M ichigan. In oonparison to most m idw estem a g r ic u ltu r a l a re a s , Michigan has a s h o r te r growing season and much low er f r a c t io n o f c a le n d a r days s u ita b le f o r f i e l d work in th e c r u c ia l p la n tin g and h a rv e s tin g p e rio d s (Tulu e t a l ., 1974). T h erefo re, th e economic advantage a s s o c ia te d w ith in c re a s in g m achinery p ro d u c tiv ity p e r u n it o f cro p lan d a re a i s more im portant in c lim a te s l i k e t h a t o f M ichigan. P rocedures f o r tr a d e o f f a n a ly s is need to be developed t o e v a lu a te p ro d u ctio n re s o u rc e req u irem en ts and c o s ts in r e l a ti o n t o a l t e r n a t i v e p h y sic a l and te c h n ic a l o rg a n iz a tio n ( s c a le and technology) o f th e p ro ­ d u ctio n u n i t . T his study developed such a procedure f o r m ajor f i e l d cro p s o f so u th ern Michigan. The crops c o n sid ered were co rn , soybeans, f i e l d bean s, wheat and a l f a l f a . The te c h n o lo g ie s s e le c te d were th o se t h a t a re used on farm s in southern M ichigan. technology were n o t co n sid ered . However, a l l form s o f In ste a d , an attem pt was made t o s e l e c t o n ly th o s e te c h n o lo g ie s t h a t re p re s e n t "p o in ts " on th e spectrum o f c u rre n t o r p o te n tia l te c h n o lo g ie s. Thus, t i l l a g e system s re p re s e n tin g th r e e le v e ls o f t i l l a g e in te n s i t y were s e le c te d . c o n sid ered were: T illa g e system s n o - t i l l , c h is e l plow and moldboard picw. The names o f th e s e t i l l a g e system s r e f e r t o th e prim ary t i l l a g e o p e ra tio n in each c a se . Farm s i z e le v e ls (cro p lan d a re a ) co n sid ere d were r e l a t e d in g e n e ra l t o th e s i z e range c u rr e n tly in e x is te n c e in th e so u th e rn p a r t o f th e s t a t e - a range which was s u f f i c i e n t f o r e v a lu a tin g th e re le v a n t economies o r diseconom ies o f s c a le . 4 1 .1 S e le c tio n o f an A p p ro p riate Approach There a r e two ways t o approach such a stu d y . A ctual o p e ra tin g system s u sin g each crop p ro d u c tio n system can be lo c a te d and an aly zed from th e in fo rm a tio n g a th e re d on s i t e . T h is approach i s d i f f i c u l t because co n p arab le system s u s in g th e same tech n o lo g y , s im ila r management and having co n p arab le w eather p a tte r n s and lan d b ase have t o be lo c a te d o v e r a s u i t a b l e ran g e o f s i z e s . A lso, in o rd e r to conpare d i f f e r e n t cro p p in g sy s­ tems w ith re s p e c t t o s e v e ra l v a r ia b le s , a l l v a r ia b le s have t o be h e ld c o n s ta n t ex cep t one, to o b serv e th e e f f e c t o f t h a t one v a r i a b le . As t h i s cannot be done in th e r e a l w orld, a s y n th e tic m odeling approach was used. To d e sig n a f i e l d m achinery system which s a t i s f i e s s p e c if ie d p h y s ic a l perform ance c h a r a c t e r i s t i c s and p r o b a b i l i s t i c c a le n d a r d a te c o n s t r a i n ts , a la r g e number o f c a lc u la tio n s a r e re q u ire d . S ince r e s u l t s were re q u ire d f o r a number o f crop p ro d u c tio n system s, a computer program was developed f o r d e sig n in g f i e l d m achinery system s. 1 .2 O b je c tiv e s o f th e Study The fo llo w in g o b je c tiv e s o f th e stu d y were fo rm u lated : 1. Tb develop a ccrrputer model t o d e sig n f i e l d m achinery system s f o r m u ltic ro p farm s i t u a t i o n s t h a t w i l l e n ab le com parison o f d i f f e r e n t cro p p ro d u c tio n system s w ith re s p e c t t o c o s ts and re q u ire m e n ts f o r m achinery, la b o r , and f o s s i l f u e l s f o r f i e l d work. 2. Tb e v a lu a te and conpare m ajor crop p ro d u c tio n system s o f so u th e rn M ichigan o v e r a range o f s i z e s . Crop p ro d u c tio n system s c o n s id e re d sh o u ld in c lu d e m ost eco n o m ically and ag ro n o m ic a lly f e a s i b l e mix o f c ro p s o f c o rn , so y b ean s, f i e l d b e an s, wheat and a l f a l f a u s in g a n o - t i l l , c h i s e l plow o r m oldboard plow t i l l a g e system . 1 .3 System B o u ndaries and D e s ira b le Model C h a r a c te r is ti c s A rn n b e r o f system c o n s t r a i n t s and model c h a r a c t e r i s t i c s were e s t a b l is h e d a t t h e o n s e t; 1. The model sh o u ld be developed f o r an in d iv id u a l fa n n in g o p e ra tio n (an in d iv id u a l firm ) t h a t e x i s t s s o l e ly f o r th e p ro d u c tio n o f f i e l d c ro p s . T here sh o u ld be no c o n p e titio n f a r men, m achine o r f i e l d tim e from o t h e r farm e n t e r p r i s e s . 2. The model sh o u ld b e a b le t o h a n d le f i e l d o p e ra tio n s f o r any m ix o f c ro p s o f c o rn , soybeans, f i e l d b e a n s, w heat and a l f a l f a u s in g n o - t i l l , c h i s e l plow o r m oldboard plow t i l l a g e system . 3. The model sh o u ld be a b le t o ta k e i n to c o n s id e r a tio n th e p ro b a­ b i l i s t i c n a tu r e o f w e a th e r and i t s e f f e c t on f i e l d m achinery re q u ire m e n ts . 4. The model sh o u ld b e a b le t o d e sig n " r e a l i s t i c ” f i e l d m achinery sy stem s and produce a sc h e d u le o f o p e ra tio n s w hich i s c o n s is te n t w ith norm al p r a c t i c e s f o r s e l e c te d c ro p p ro d u c tio n sy stem s o v e r a s u i t a b l e ra n g e o f farm s i z e s . 5. The ra n g e o f s i z e s c o n s id e re d f o r each c ro p p in g system sh o u ld , in g e n e r a l, b e r e l a t e d t o t h e ra n g e c u r r e n t ly i n e x is te n c e in s o u th e rn M ichigan and t o th e ra n g e w hich i s s u f f i c i e n t f o r e v a lu a tin g r e le v a n t econom ies o r diseconom ies o f s c a l e . 6. The te c h n o lo g y c o n s id e re d sh o u ld c o n s i s t o f s e l f - p r o p e l l e d c o itb in es and tw o -v h ee l d r i v e t r a c t o r s . T h is w i l l s im p lif y t h e model s t r u c t u r e and s t i l l b e a b le t o r e p r e s e n t most o f th e M ichigan fa rm s. T h e re fo re , farm s i z e s c o n s id e re d sh o u ld be l a r g e enough t o r e q u i r e t h e u se o f s e l f - p r o p e l l e d com bines, b u t b ig farm s t h a t u se fo u r-w h e e l d r iv e t r a c t o r s s h o u ld n o t b e c o n s id e re d . 7. S in c e d a ta o f e q u a l r e l i a b i l i t y on tim e li n e s s c o s t o f d i f f e r e n t o p e r a tio n s i s n o t a v a i l a b l e f o r a l l c ro p s , t im e li n e s s o o st s h o u ld a p p e a r a s a c o n s t r a i n t r a t h e r th a n a s a component o f an o b j e c ti v e f u n c tio n . The model s h o u ld p ro d u ce r e s u l t s f o r d i f f e r e n t c ro p p in g sy stem s w hich a r e c o n p a ra b le . 8. In M ichigan custom h i r i n g , l e a s i n g , and o t h e r ty p e s o f s h a r in g o f eq uipm ent, may o c c a s io n a lly b e p r a c t ic e d , b u t i s n o t cam ion. T h e re fo re , e a c h fir m sh o u ld have co m p lete c o n tr o l o f i t s m achinery s y s te m 9. In a d d itio n t o t h e f i e l d m achinery s e t , t h e model s h o u ld p ro v id e w eekly l a b o r re q u ire m e n ts , f u e l consum ption and m onetary c o s t s a s s o c i a t e d w ith t h e m achinery s e t f o r e ac h c ro p p ro d u c tio n sy stem . 10. The r e s u l t s s h o u ld b e o b ta in e d f o r w e ll- d r a in e d Miami -C onover loam s o i l s w hich a r e cannon in so u th e rn M ichigan. 2. REVIEW QF LITERATURE The d e sig n o f f i e l d m achinery system s in v o lv e s c a lc u la tio n o f m achine p r o d u c tiv itie s , e stim a tio n o f s u i t a b l e f i e l d work tim e, s e le c tio n o f an a p p ro p ria te perform ance c r i t e r i a and development o f a s u ita b le p ro ced u re f o r o p tim izin g perform ance c r i t e r i a s u b je c t t o s p e c ifie d c o n s tr a in ts . 2 .1 Machine P r o d u c tiv itie s The m ajor f a c to r s in flu e n c in g th e p ro d u c tiv ity o f a machine a re s iz e , o p e ra tin g speed, f i e l d e ff ic ie n c y and energy re q u ire m e n ts. The a v a ila b le s iz e s o f v a rio u s m achines can be o b ta in e d frcm p r i c e l i s t s o f farm m achinery m anufacturers such a s th e A g ric u ltu ra l Whole Goods P r ic e L is t o f Deere and Coupan y , o r from Implement and T ra c to rs Red Book (1977). F ie ld e ff ic ie n c y i s a measure o f r e l a t i v e p r o d u c tiv ity o f a machine u n d er f i e l d c o n d itio n s . I t acco u n ts f o r f a i l u r e t o u t i l i z e th e t h e o r e t i c a l o p e ra tin g w idth o f th e machine and f o r tim e lo s s e s due t o tu r n in g , i d l e t r a v e l , m a te ria l h a n d lin g , c le a n in g clogged equipm ent, and f i e l d r e p a i r and m aintenance. I t i s n o t a c o n s ta n t v a lu e f o r a s p e c i f i c m achine b u t v a r ie s w idely. Hunt (1977) d e scrib e d v a rio u s f a c t o r s a f f e c tin g th e f i e l d e ff ic ie n c y o f a m achine. T yp ical rang es in o p e ra tin g speed and f i e l d e ff ic ie n c y f o r most ty p e s o f m achines a re 7 8 giv en in th e A g ric u ltu ra l E ngineers Yearbook (1977), which summarizes d a ta p r io r t o 1971, and elsew here (Hunt, 1977; Bowers, 1970). F ie ld machine energy req u irem en ts c o n s is t o f fu n c tio n a l requirem en ts and r o l l i n g r e s is ta n c e req u irem en ts. F u n c tio n a l req u irem en ts a re th o se t h a t r e l a t e d i r e c t l y t o th e p ro ce ssin g o f s o i l s , se ed s, chem icals o r c ro p s . R o llin g r e s is ta n c e power req u irem en ts a r i s e from th e n e c e s s ity f o r moving heavy m achinery o ver s o f t f i e l d s u rfa c e s . F u n ctio n al req u irem ents depend upon s o i l and crop c o n d itio n s which a re h ig h ly v a ria b le . T illa g e d r a f t v a r ie s w ith s o i l ty p e , s o i l m o istu re, ro o t development, o rg a n ic m a tte r co n ten t and depth o f p e n e tra tio n . Forward speed a ls o s i g n i f ic a n t l y a f f e c t s plow d r a f t (A g ric u ltu ra l E ngineers Yearbook, 1977). To p ro v id e an in d ic a tio n o f th e degree o f v a r i a b i l i t y , r e l a t i v e draw bar p u l l s f o r moldboard plows in d i f f e r e n t s o i l s a re l i s t e d below (Hunt, 1977): Sandy s o i l 1 .0 Clay loam 2 .3 Heavy c la y sod 3.6 Sandy loam 1 .6 Clay 2 .8 Moist gumbo 5 .5 S i l t loam 2 .0 Heavy c la y 3 .3 Dry adobe 7.8 D ra ft o f t i l l a g e implements i s norm ally re p o rte d p e r u n i t o f e f f e c t i v e w idth o r p e r row. R o llin g and fu n c tio n a l requirem ents a re combined f o r most t i l l a g e and ground d riv e n m achines (Hunt, 1977). o f d r a f t , energy o r power req u irem en ts f o r most f i e l d m achines a r e l i s t e d in th e A g ric u ltu ra l E ngineers Yearbook (1977) and elsew here (Hunt, 1977; Bowers, 1970). White (1975b) p u b lish e d d r a f t re q u ire ­ m ents o f v a rio u s m achines under M ichigan c o n d itio n s . Ranges 9 2 .2 S u ita b le F ie ld Work Days The r e l a t i o n o f th e f r a c t io n o f c a le n d a r days s u i t a b l e f o r f i e l d work t o c lim a tic and s o i l c o n d itio n s h as been modeled f o r Michigan (T ulu e t a l . , 1974), a s w ell as f o r s e v e r a l o th e r a re a s . V arious te c h n iq u e s have been used t o d eterm in e t h i s r e l a t i o n . Records o f observed numbers o f s u i t a b l e f i e l d work days have been re p o rte d by Link (1962) from th e p e rs o n a l d ia r y o f th e manager o f th e Ames, Iowa, Agronomy Farm (1932-1939, 1942-1961) and by Morey e t a l . (1972) from f i e l d o b se rv e rs in c e n t r a l In d ia n a (1952-1968). The o b s e rv a tio n s o f s u i t a b l e days w ere made on a s in g le farm o r f o r a p a r t i c u l a r re g io n in a l l c a se s r e s t r i c t i n g t h e i r v a l i d i t y to th a t s itu a tio n . F u lto n and Ayres (1976) re p o rte d observed numbers o f s u i t a b l e days in Iowa a t d i f f e r e n t p r o b a b i l it y l e v e l s f o r f i e l d o p e ra tio n s th ro u g h o u t th e cro p season based on re c o rd s o f Iowa Crop and L iv esto ck R e p o rtin g S e rv ic e . C a rp e n te r and B rooker (1970) d eterm ined s u i t a b l e days f o r corn h a rv e s tin g i n M isso u ri from h i s t o r i c a l c lim a to lo g ic a l re c o rd s . A day on w hich any one o f th e fo llo w in g c o n d itio n s o c c u rre d was assumed to b e an u n s u ita b le day f o r co m h a rv e s tin g : D aily p r e c i p i t a t i o n > (Tenp. + 1 7 .7 8 )/8 .7 4 9 Two-day accum ulated p r e c i p i t a t i o n > (Temp. + 1 7 .7 8 )/4 .3 7 4 T hree-day accum ulated p r e c i p i t a t i o n > (Temp. + 1 7 .7 8 )/2 .1 8 7 F our-day accum ulated p r e c i p i t a t i o n > (Temp. + 1 7 .7 8 )/1 .0 9 4 F iv e-d ay a cc u n u la te d p r e c i p i t a t i o n > (Tenp. + 1 7 .7 8 )/0 .5 4 7 Snow fall > 25 rim Snowdepth > 25 ran 10 A ll te m p e ra tu re s were average d a ily tem p era tu re in °C. They a ls o assumed t h a t s o i l would be fro z e n on any day w ith an average tem p eratu re l e s s th a n -6 .7 °C (20°F) and c l a s s i f i e d such days a s s u i t a b l e f o r h a rv e s tin g r e g a r d le s s o f p r e c i p i t a t i o n i f sn o w fall and d ep th o f snow were b o th l e s s th a n 25 ran. No v a lid a tio n o f th e model was re p o rte d . S e v e ra l i n v e s tig a to r s have u sed s o i l m o istu re c o n te n t a s a c r i t e r i o n f o r s u i t a b l e f i e l d work days. Shaw (1965a) used a s o i l m o istu re b u d g e tin g te c h n iq u e t o e s tim a te th e m o istu re c o n te n t in th e to p 152 ran o f s o i l p r o f i l e from d a ily p r e c i p i t a t i o n and e v a p o ra tio n f o r C la rio n W ebster s o i l s o f Iowa. He assumed t h a t s o i l was w orkable any day when i t was n o t fro ze n and th e a v a ila b le s o i l m o istu re in th e to p 152 mm o f th e p r o f i l e was l e s s th a n o r e q u a l t o 19 ran ( a v a ila b le w a te r c a p a c ity = 23 ran). He conpared th e number o f p r e d ic te d days s u i t a b l e f o r f i e l d o p e ra tio n s t o th e re c o rd o f s u i t a b l e days from th e o ld Agronomy Farm, Ames, Iowa (L in k , 1968). The c o r r e l a t io n s between th e observed and p r e d ic te d number o f days d u rin g March, A p r i l , and May ranged from 0 .8 7 to 0 .9 3 . B olton e t a l . (1968) developed a s o i l m o istu re acco u n tin g tech n iq u e t o e s tim a te s o i l m o is tu re c o n te n t on any day from re c o rd s o f r a i n f a l l and pan e v a p o ra tio n . From a tw o -y ear re c o rd o f days s u i t a b l e f o r f i e l d o p e ra tio n s a t th e D e lta Branch Experim ent S ta tio n , S to n e v ille , M is s is s ip p i, th e y c l a s s i f i e d a day a s a workday i f th e s o i l m o istu re in th e 152 ran s u rfa c e l a y e r was 80 p e rc e n t o f f i e l d maximun f o r t i l l a g e o p e ra tio n s and 85 p e rc e n t f o r n o n tilla g e o p e ra tio n s f o r s i l t y c la y and sandy s o i l s . F o r c la y s o i l s m o is tu re must be a t o r below 78 p e rc e n t o f f i e l d maximum f a r a l l f i e l d o p e ra tio n s . 11 Link (1968) a ls o u se d a m o is tu re b u d g e tin g te c h n iq u e t o e s tim a te d a ily s o i l m o is tu re c o n te n ts . He proposed th e p l a s t i c l i m i t a s th e maximum v a lu e f o r th e s o i l t o b e t r a f f i c a b l e , and su g g e ste d t h a t f i e l d c o n d itio n s s u i t a b l e f o r t i l l a g e o p e ra tio n s c o u ld b e d e fin e d by a maximum s o i l m o is tu re c o n te n t below t h e p l a s t i c l i m i t and some minimum s o i l m o is tu re c o n te n t. R utledge and McHardy (1968) p a r t i t i o n e d th e s o i l i n to s i x m o istu re zo n es and u sed a s o i l m o is tu re budget developed by B a ie r and R obertson (1966) t o e s tim a te t h e s o i l m o is tu re c o n te n t in each zone from c liro a t o l o g i c a l re c o rd s . They a ls o c a l c u l a t e d v a lu e s o f s o i l s h e a r s tr e n g th r e q u ir e d f o r t i l l a g e o f A lb e rta s o i l s , and concluded t h a t re q u ire d s h e a r s tr e n g th w ould b e developed a t s o i l m o is tu re c o n te n ts a t o r below f i e l d c a p a c ity . They o b ta in e d a good c o r r e l a t i o n w ith o b serv ed days s u i t a b l e f o r t i l l a g e when 95 p e rc e n t o f a v a i la b l e w a te r c a p a c ity was u se d a s t h e maximum s o i l m o is tu re c o n te n t i n t h e to p t h r e e zones and th e r e s t r i c t i o n o f no snow on th e ground was in c lu d e d . P e te rs o n and F ris b y (1969) u se d w ind tu n n e l s t u d i e s t o d evelo p an e q u a tio n f o r th e d ry in g r a t e o f s o i l a t m o is tu re c o n te n ts above f i e l d c a p a c ity . F ris b y (1970) u se d t h i s e q u a tio n and a s o i l m o is tu re b u d g e tin g te c h n iq u e f o r p r e d i c ti n g th e number o f good days a v a i la b l e f o r p rim ary t i l l a g e in th e s p r in g and f a l l f o r a s o i l in c e n t r a l M isso u ri. He c l a s s i f i e d a day a s s u i t a b l e f o r t i l l a g e i f t h e s o i l m o is tu re c o n te n t was e q u a l t o o r l e s s th a n f i e l d c a p a c ity and i f p r e c i p i t a t i o n was l e s s th a n 2 .5 ran. Morey e t a l . (1971) u se d a s o i l m o is tu re b u d g e tin g te c h n iq u e developed by Shaw (1963) and t r a c t a b i l i t y c r i t e r i a b a se d p r im a r ily on t h e r e s u l t s o f R u tled g e and McHardy (1968) t o e s tim a te th e number o f 12 days s u ita b le f o r h a rv e s tin g co m in c e n tr a l In d ian a. A s u ita b le day was d e fin e d a s one having le s s th an 2 .5 mn o f p r e c ip ita tio n and a m o istu re c o n te n t l e s s th an 95 p e rc e n t o f a v a ila b le w a ter c a p a c ity in th e to p 152 mn o f th e s o i l p r o f i l e . S e l i r i o and Brown (1972) e stim a te d sp rin g workdays in O n tario from c lim a to lo g ic a l re c o rd s . Based on two y e a rs o f s o i l m o istu re measurements and o b se rv a tio n o f work c o n d itio n s , th e y concluded th a t c u lt i v a t io n was p o s s ib le when th e s o i l m o istu re c o n te n t was about 90 p e rc e n t o f th e f i e l d c a p a c ity v a lu e t o a depth o f 120 mn r e g a rd le s s o f s o i l m o istu re c o n te n t in th e lower zones. A day was assumed to be s u ita b le f o r f i e l d work i f th e -top 120 mn o f th e s o i l was a t o r below 90 p e rc e n t o f f i e l d c a p a c ity , d a ily sn o w fall was l e s s th an 25 mn and maximum a i r te n p e r a tu re was above 0°C (3 2 °F ). Holtman e t a l . (1973) used a com bination o f th e s o i l m o istu re budgets developed by Shaw (1963) and B a ie r and R obertson (1966) to e stim a te a v a ila b le s o i l m o istu re in th e top 152 ram o f th e s o i l p r o f i l e . They d e fin e d a day a s s u ita b le f o r co m h a rv e s tin g i f th e a v a ila b le w ater c a p a c ity in th e upper 76 mn o f th e s o i l p r o f i l e was below 95 p e rc e n t on lig h t s o ils . F o r heavy w e ll d ra in e d s o i l s , th ey proposed t h a t p e rc e n t a v a ila b le w a ter c a p a c ity in th e second 76 mn o f th e s o i l p r o f i l e must a ls o be below 98 o r 99 p e rc e n t. They d id n o t determ ine v e h ic le m o b ility when s o i l was fro z e n . Tulu (1973) extended th e work o f Holtman e t a l . t o fro z e n s o i l . The models o f F rid le y and Holtman (1972) were employed t o compute s o i l fre e z in g and thaw ing d a te s re q u ire d f o r s o i l m o istu re budget. He assumed a day was s u i t a b l e f o r corn h a rv e s tin g i f th e s o i l was fro zen o r i f thawed th e a v a ila b le w ater c a p a c ity in th e upper 76 nrn o f s o i l 13 p r o f i l e was below 95 p e rc e n t. For sp rin g t i l l a g e and p la n tin g o p e ra tio n s , a workday was assumed i f th e a v a ila b le w ater c a p a c ity in th e upper 76 mn o f s o i l p r o f i l e was below 95 p e rc e n t and in th e second 76 mn o f th e s o i l p r o f i l e was below 98.5 p e rc e n t. He v e r i f i e d th e model r e s u l t s w ith observed workdays from th r e e n o rth e rn In d ian a farm s f o r 1970. K ish and P r i v e tt e (1974) e stim a te d th e number o f f i e l d work days a v a ila b le f o r t i l l a g e on South C a ro lin a s o i l s based on a s o i l m oistu re budget o f th e upper 305 run o f th e s o i l . The p erc en ta g e o f f i e l d c a p a c ity a t o r below which s o i l s were assuned t o be t i l l a b l e v a rie d from 70 to 95. They d id n o t r e p o r t any f i e l d s o i l m o istu re measurements to support c o n sid e re d l i m i t s . Hassan and Broughton (1975) s t a t e d t h a t t r a c t a b i l i t y c r i t e r i a f o r seed bed p re p a ra tio n appeared t o be a ff e c te d by th e m o istu re s t a t e in th e upper 25 nm and second 51 mn o f s o i l p r o f i l e based upon lim ite d f i e l d o b se rv a tio n s. The lim itin g p e rc e n ta g e s o f a v a ila b le w a ter c a p a c ity in th e upper 25 mn and next 51 ran o f s o i l p r o f i l e f o r c la y , c la y loam and sandy loam s o i l s o f th e MacDonald C ollege Farm, S t. Lawrence Lowlands, Quebec were re p o rte d by th a n t o be 10, 97; 50 , 93; and 66 , 9 8 .2 ; r e s p e c tiv e ly . Ayers (1975) used s o i l m o istu re budg etin g tec h n iq u e s developed by Shaw (1963, 1965b) f o r p r e d ic tin g s u i t a b l e days f o r co m h a rv e s tin g in Iowa. Records o f good and bad f i e l d days from th e o ld Agronomy Farm, Ames, Iowa (Link, 1962) were used t o s e l e c t th e v a lu e s o f th e d e c isio n p aram eters by s e n s i t i v i t y a n a ly s is . The v a lu e s o f p aram eters in th e model t h a t had th e b e s t agreem ent w ith th e e ig h t- y e a r o b se rv a tio n s were: 14 Maximum p r e c i p i t a t i o n y e ste rd a y 1 3 .7 mu Maximum p r e c i p i t a t i o n today Unfrozen s o i l 6 .9 mn Frozen s o i l 2 .5 mn Maximum a v a ila b le s o i l m o is tu re , 0-152 mn 2 6 .7 mn Maximum sn o w fall 2 5 .4 ran Maximum d e p th o f snow on th e ground 0 .0 0 ran E l l i o t e t a l . (1977) developed a s o i l m o istu re b a la n c e model t o p r e d ic t days a v a ila b le f o r s o i l t i l l a g e in I l l i n o i s d u rin g th e s p rin g m onths. P e rc e n t o f th e a v a ila b le s o i l m o istu re in th e upper 150 ran o f s o i l was used a s a t i l l a g e c r i t e r i o n , 80 p e rc e n t f o r f i n e sandy loam s o i l s and 90 p e rc e n t f o r s i l t loam s o i l s . They t e s t e d t h e model a g a in s t f i e l d work day d a ta from th e I l l i n o i s C o o p erativ e Crop R ep o rtin g S e rv ic e and l o c a l d a ily f i e l d o b s e rv a tio n s o f fa v o ra b le workdays and found i t t o b e s u f f i c i e n t t o p r e d ic t a v a ila b le t i l l a b l e days on a m onthly b a s i s . 2 .3 S e le c tio n C r ite r io n Ih e s e le c tio n c r i t e r i o n used in m achinery system d e sig n i s most o f te n an economic one, i . e . l e a s t c o s t o r maximum p r o f i t (H unt, 1963; F ris b y and Bockhop, 1968; Burrow and Siemens, 1974; MacHardy, 1 9 6 6 a,b ). The c o s ts c o n sid e re d a r e m achinery, la b o r and tim e lin e s s . 15 2 ,3 .1 Machinery c o s ts Machinery c o s ts a r e d iv id e d i n to two c a te g o r ie s , f ix e d c o s ts and v a r ia b le c o s ts . V a ria b le c o s ts in c re a s e p ro p o r tio n a lly w ith th e u se o f th e m achine, w h ile fix e d c o s ts a r e independent o f u se . The c o s ts o f i n t e r e s t on m achinery in v estm en t, ta x e s , housing, and in su ra n c e axe dependent on c a le n d a r y e a r tim e and a r e independent o f u se . The c o s ts o f f u e l , l u b r ic a t i o n , d a ily s e r v ic e and m aintenance a r e a s s o c ia te d w ith u se . D e p re c ia tio n and c o s t o f r e p a ir in g seem t o b e a fu n c tio n o f b o th u se and tim e . B ut, m ost o fte n d e p re c ia tio n i s in c lu d e d in th e f ix e d c o s t c ate g o ry and r e p a i r c o s t in th e v a r ia b le c o s t c a te g o ry . D e ta ile d p ro c e d u re s f o r e s tim a tin g m achinery c o s ts a r e a v a ila b le in Hunt (1977) and elsew here (A g r ic u ltu r a l E n g in eers Yearbook, 1977; Bowers, 1970). E stim a te s o f th e s e c o s ts can b e found in e x te n sio n b u l l e t i n s o f v a rio u s A g r ic u ltu r a l E n g in e erin g d epartm ents (S ta p le to n and Hinz, 1974; E id sv ig and O lson, 1969; W aters and Daun, u n d a te d ). F a irb an k s and L arson (1971) have p u b lis h e d c o s ts o f u sin g farm m achinery b ased on a survey o f th e b e s t farm e rs in K ansas. Hunt (1974) has r e p o r te d th e r e s u l t s o f an e ig h t- y e a r m o n ito rin g o f th e r e p a i r and m aintenance c o s ts o f 745 m achines on I l l i n o i s farm s. 16 2 .3 .2 Labor c o s ts F o r a g ro w e r-o p e ra to r o f a farm , th e la b o r c o s ts a r e th e o p p o rtu n ity c o s t o f o p e ra to r tim e u se d f o r o p e ra tin g m achinery. I f h ir e d la b o r i s u sed , t h e c o s t may b e on an h o u rly o r an n u al b a s i s . Cn an h o u rly b a s i s , t o t a l la b o r c o s t i s d i r e c t l y p r o p o r tio n a l t o m achine o p e ra tin g tim e . When la b o r i s h ir e d on an an n u al b a s i s , t o t a l la b o r c o s t i s in d ependent o f m achine o p e r a tin g tim e . Burrows and Siemens (1974) computed la b o r c o s t assum ing t h a t each man was h i r e d a t an annual s a l a r y , f u l l tim e , o n ly t o o p e ra te m achinery. Hughes and Holtman (1974) assum ed h i r e d la b o r on an h o u rly b a s i s . 2 .3 .3 T im e lin e ss c o s ts T im e lin e ss i s a m easure o f a b i l i t y t o p erfo rm a jo b a t a tim e t h a t g iv e s optimum q u a l i t y and q u a n tity o f p ro d u c t. I f t h e m achine system does n o t have enough c a p a c ity t o perform th e jo b w ith d e s ir e d r e s u l t s , th e v a lu e o f c ro p l o s s i s c o n s id e re d an economic p e n a lty f o r p o o r tim e lin e s s . T im e lin e ss p e n a lty c o s t s in c lu d e red u ced y i e l d from im proper t i l l a g e , seedbed p r e p a r a tio n and p la n tin g o p e ra tio n s ; l o s s e s a s s o c ia te d w ith im proper tim in g o f m achine o p e ra tio n s t o b io lo g i c a l n eed s o f th e m a tu rin g p l a n t ; and any r e d u c tio n i n p ro d u c t q u a l i t y t h a t may be a t t r i b u t e d t o u n tim e ly m achine o p e r a tio n s . n e a r z e ro tim e lin e s s c o s t s . Some o p e ra tio n s may have O th e rs , p a r t i c u l a r l y t h e h a rv e s t o f h ig h ly p e r is h a b le p ro d u c ts , may have v e ry h ig h tim e lin e s s c o s ts ( A g r ic u ltu r a l E n g in e e rs Yearbook, 1977). 17 A tim e li n e s s l o s s c u rv e ( r e l a t i o n s h i p betw een c ro p v a lu e and th e o p e ra tic * ! d a te ) v a r i e s w ith o p e r a tio n , c ro p , farm l o c a t i o n , and even from one y e a r t o a n o th e r . Hunt (1977) and Bowers (1970) gave e s tim a te s o f t im e li n e s s l o s s f a c t o r ( f r a c t i o n a l re d u c tio n in y i e l d o r v a lu e o f t h e c ro p p e r a c re -d a y o f d e la y ) f o r seme s p e c i f i c c ro p s and o p e r a tio n s . They assum ed a l i n e a r re d u c tio n i n y i e l d ( o r v a lu e ) o f c ro p a f t e r an optimum d a te . S in c e r e l i a b l e d a ta f o r tim e li n e s s c o s t s o f a l l o p e r a tio n s and f o r a l l c ro p s i s n o t r e a d i l y a v a i l a b l e f o r a l l l o c a t i o n s , some i n v e s t i g a t o r s (Hughes and H oltm an, 1974; Bowers, 1975) c o n s id e re d t im e li n e s s a s a system d e s ig n c o n s t r a i n t . S u ita b le c a le n d a r p e r io d s f o r eac h o p e r a tio n w ere e s t a b l i s h e d and m achinery s y s ta n s i z e was o p tim iz e d s u b j e c t t o t im e li n e s s c o n s t r a i n t s . 2 .4 M achinery System D esign P ro c e d u re s R e fe re n c e l i t e r a t u r e c o n ta in s ranch d a ta on t h e c o s t s o f o p e r a tin g farm f i e l d equipm ent, b u t few p u b l ic a t i o n s have c o n s id e re d t h e problem o f c a p a c ity o r s i z e s e l e c t i o n . The e s s e n t i a l m ethodology f o r m atch in g t h e s i z e o f ground en g ag in g im plem ents t o t r a c t o r power and f o r c a l c u l a t i n g p r o d u c t i v it y i s g iv e n i n t h e A g r ic u ltu r a l E n g in e e rs Y earbook (ASAE, 1 9 7 7 ). Hunt (1963, 1966) p r e s e n te d p ro c e d u re s f o r s e l e c t i n g f i e l d m achinery on a n econom ic b a s i s . Annual c o s t e q u a tio n s f o r each im plem ent w ere w r i t t e n i n te rm s o f e f f e c t i v e w id th o f im plem ent and f o r t h e t r a c t o r i n te rm s o f maximum PTO pow er. Each a n n u al c o s t e q u a tio n in c lu d e d a te rm f o r t im e li n e s s c o s t a s s o c ia te d w ith t h a t o p e r a tio n . The l e a s t c o s t 18 s iz e f o r each machine was determ ined in dependently o f th e o th e rs by d i f f e r e n t i a t i n g th e annual c o st e q u a tio n w ith re s p e c t to th e p e r tin e n t v a ria b le and s e t t i n g th e d i f f e r e n t i a l equal to z e ro . Hunt (1972) d e sc rib e d a s im ila r p roced ure f o r determ in in g th e economic power le v e l f o r b ig t r a c t o r s . Scarborough and Hunt (1973) m odified th e s e programs by in c lu d in g a lg o rith m s f o r determ in in g optimum replacem ent p e rio d s f o r th e equipment and f o r sch ed u lin g o p e ra tio n s which a re c o m p e titiv e in n a tu re . Link and Bockhop (1964) approached s e le c tio n from a sch ed u lin g view point. They p re s e n te d an a n a ly tic a l approach f o r m atching a m achinery system t o a s e t o f farm jo b req u irem en ts and e v a lu a tin g th e match f o r tim e lin e s s o f o p e ra tio n . P r o b a b i li t ie s o f com pletion o f f i e l d work w ith in s p e c if ie d p e rio d s w ere used. F risb y and Bockhop (1968) used L in k 's model t o determ ine acreag e y ie ld in g maximum incane f o r a given machinery system . Three s e p a ra te jo b sequences f o r th e c u ltu r e o f a s in g le cro p , c o m , were c o n sid ere d . Machinery ownership c o st and th e v a lu e of crop l o s t due to incom plete h a rv e st were s u b tra c te d from g ro ss income t o c a l c u l a t e income f o r a given farm s iz e w ith a given m achinery system . Plowing c a p a c ity and h a rv e s tin g c a p a c ity were no t b alan ced in sane s y s ta n s . They su g g ested t h a t th e s e system s be m odified by in c re a s in g plow ing c a p a c ity u n t i l th e maximum acreag e lim ite d by h a rv e stin g c a p a c ity i s o b ta in e d . MacHardy (1966a) d e sc rib e d a method u sin g Lagrange M u ltip lie rs f o r d eterm ining th e miniraim c o s t m achinery com bination. The method determ ines implement p r o d u c tiv itie s and t r a c t o r horsepow er such t h a t annual fix e d m achinery c o st i s a miniimin. MacHardy (1966b) d e sc rib e d a procedure 19 f o r s e le c tin g m achinery s iz e by m inim izing th e sum o f annual fix e d m achinery and tim e lin e s s c o s ts . Using cum ulative d i s t r ib u t i o n curves f o r c o n se c u tiv e good and bad days and a Monte C arlo approach, a g ra in combining o p e ra tio n was sim u la te d . A se arc h on s iz e y ie ld e d th e optimum Burrows and Siemens (1974) developed a computer program to determ ine l e a s t c o s t m achinery mix f o r com -soybean farm s in th e corn b e l t . A se a rc h was conducted on a sim u la tio n which c o n sid ere d m achinery, la b o r, and corn p la n tin g tim e lin e s s c o s ts . Hie sim u la tio n was based on workday p r o b a b i l i t i e s developed from d a ta given by Link (1968) f o r th e Ames, Iowa, Agronomy Farm. Hie optimum m achinery s e t and th e number of men re q u ire d was determ ined b y m a k in g s e v e ra l t r i a l s . For each se a rc h t r i a l a l l t r a c t o r s and c a rb in e s were equal in s i z e . In sch ed u lin g f i e l d o p e ra tio n s a t r a c t o r was c o n tin u a lly a ssig n e d t o a f i e l d o p e ra tio n u n t i l th e o p e ra tio n was com pleted. Hughes and Holtman (1974) developed a computer program f o r s e le c tin g and s iz in g m achinery system s based upon c a le n d a r d a te c o n s tr a in ts on f i e l d o p e ra tio n s . F ie ld o p e ra tio n s were o rg an ized in to s u b s e ts . Each su b se t was a group o f f i e l d o p e ra tio n s t h a t must be perform ed e i t h e r sim u lta n eo u sly o r s e q u e n tia lly d u rin g a s p e c i f i c tim e p e rio d . n e ss c o s ts w ere n o t c o n sid ered e x p l i c i t l y . T im eli­ R ath er, a c a le n d a r p e rio d c o n s tr a in t was assumed f o r each su b se t o f o p e ra tio n s . I t was assumed t h a t a l l f i e l d o p e ra tio n s used th e same fix e d p e rc en ta g e o f r a te d t r a c t o r draw bar power a t a l l tim e s and su b se t tim e was d iv id e d among o p e ra tio n s acc o rd in g t o th e energy req u irem en ts o f th e o p e ra tio n s . The e f f e c t i v e horsepower re q u ire d f o r th e system was th e maximum o f t h a t re q u ire d f o r any one s u b s e t. I t was p o s s ib le to reduce t h i s 20 maximum horsepow er by m anually m odifying th e d i s t r i b u t i o n o f work among s u b s e ts (where agronom ically f e a s i b l e ) and re -ru n n in g th e program . Bower (1975) d e s c rib e d a s im ila r p ro ced u re f o r m achinery s e le c tio n which he used f o r a 50,000 h e c ta re fan n in g o p e ra tio n in Y ugoslavia. A t r a c t o r s i z e was assumed and im plem ents were m atched t o th e t r a c t o r . A tim e lin e s s c o n s tr a in t was in clu d ed by re q u ir in g t h a t o p e ra tio n s be com pleted b e fo re y ie ld s s t a r t e d re d u c in g a t an a c c e le r a te d r a t e . C alendar d a te c o n s t r a i n ts w ere a d ju s te d m anually t o o b ta in th e l e a s t c o s t f e a s i b l e a ll o c a t io n o f f i e l d work o v e r tim e . The tim e lin e s s c o s t d a ta o f eq u al r e l i a b i l i t y f o r f i e l d o p e ra tio n s o f a l l th e c ro p s t o be c o n sid ere d in t h i s stu d y i s n o t a v a ila b le f o r so u th e rn M ichigan c o n d itio n s . T h e re fo re , th e a lg o rith m s t h a t d e sig n m achinery s y s ta n s by o p tim iz in g an economic o b je c tiv e fu n c tio n co u ld n o t b e used f o r t h i s stu d y . And a ls o , s in c e a la r g e number o f crop p ro d u c tio n s y s ta n s was t o be compared o v e r a ran g e o f s i z e s , th e com puter a lg o rith m s t h a t do n o t c o n p le te ly autom ate d e sig n c a lc u la tio n s were n o t s u i t a b l e f o r t h i s stu d y . T h ere fo re , i t was d ecid ed t o develop a new com puter a lg o rith m t h a t s a t i s f i e d a l l th e system c o n s t r a i n ts and have d e s ir a b le model c h a r a c t e r i s t i c s d e s c rib e d in s e c tio n 1 .3 . 3. SYSTEM MODEL The system model d e s c rib e d h e re in d e s ig n s a f i e l d m achinery system f o r a m il t ic r o p farm s i t u a t i o n b a sed on tim e c o n s t r a i n t s . The m achinery system d e sig n p ro c e d u re b a s i c a l l y c o n s i s t s o f a s e r i e s o f su b o p tim iz a tio n s by i t e r a t i v e s e a rc h , s u b je c t t o c o n s t r a i n t s on t h e c o n p le tio n o f each o p e ra tio n by t h e s p e c i f i e d d a te w ith t h e s p e c i f i e d d e sig n p r o b a b i l it y . F o r each s u b o p tim iz a tio n , s u i t a b l e f i e l d work tim e t h a t can be e x p ec te d f o r a g iv en d e sig n p r o b a b i l i t y l e v e l i s c a l c u l a t e d f o r each o p e ra tio n . A m achine w id th o r power l e v e l i s assumed and th e p r o d u c tiv ity o f each o p e ra tio n i s c a l c u l a t e d s u b je c t t o c o n s t r a i n t s on a v a ila b le power, im plem ent s i z e and sp e e d . The f i e l d tim e re q u ir e d f o r each o p e ra tio n i s d e te rm in e d by d iv id in g t o t a l c ro p a re a by th e p r o d u c tiv ity o f t h e o p e r a tio n . T h is r e s u l t i s compared w ith th e a v a i la b l e f i e l d tim e w ith in t h e s p e c i f i e d c a le n d a r d a te c o n s t r a i n t s . I f th e re i s a d i f f e r e n c e betw een t h e a v a i l a b l e f i e l d tim e and th e r e q u ire d f i e l d tim e , t h e assu m p tio n i s a d ju s te d and t h e p ro c e d u re re p e a te d u n t i l a s m a lle s t m u ltip le o f b a s i c m achine w id th o r 0 .7 5 PID kW (1 HP) power l e v e l i s re a c h e d t h a t makes t h e r e q u ir e d f i e l d tim e e q u al t o o r l e s s th a n t h e a v a i la b l e f i e l d tim e . The s e l e c t i o n p ro c e d u re p ro ce ed s in a seq uence o f t h i s ty p e o f s u b o p tim iz a tio n s on h a r v e s tin g c a p a c ity , t r a c t o r power, and im plem ents. In each su b o p tim iz a tio n maximum m u ltip le u s e o f each u n i t o f equipm ent i s made. 21 22 The sequence o f s u b o p tim iz a tio n s e s t a b l i s h e s a low er bound on th e rnsnber and s i z e o f each r e q u ir e d m achinery com ponent. An o p e ra tio n sche­ d u le i s p re p a re d t o d e te rm in e w h eth er th e s e l e c te d m achinery system i s s u f f i c i e n t t o s a t i s f y a l l d a te c o n s t r a i n t s a t th e g iv en d e sig n p r o b a b i l it y . I f any d a te c o n s t r a i n t i s v i o l a t e d , an ad ju stm en t i s made in th e number o f implement u n i t s o r in th e t r a c t o r power. An o p e ra tio n s sc h e d u le i s a l s o d eveloped f o r an a v erag e y e a r (50 p e rc e n t p r o b a b i l i t y ) t o p ro v id e an i n d ic a tio n o f t h e tim e lin e s s c o s t in v o lv e d w ith th e s e le c te d m achinery s e t , and t o d e te rm in e th e la b o r d i s t r i b u t i o n d u rin g th e y e a r . C o st c a l c u l a t i o n s a r e made t o e s tim a te t h e av erag e annual c o s ts o f th e s e l e c te d m achinery system . F ig u re 3 .1 shews a s im p li f i e d g e n e ra l flow diagram o f t h e p ro c e d u re . The l i s t i n g and o t h e r d e t a i l s o f th e com puter program which was developed by t h e a u th o r f o r t h i s stucfy a r e g iv en in th e forthcom ing A g r ic u ltu r a l Economics R eport Number 331 (S ingh and Connor, 1978). Here th e m ethodology i s d e s c rib e d u s in g a s an exam ple a 446 h e c ta r e (1102 a c r e ) c o m - c o m soybean-w heat c ash c ro p farm i n s o u th e rn M ichigan. 3 .1 In p u t D ata The r e q u ir e d in p u t d a ta c o n s i s t o f : 1. Farm s i z e , 2. Crop r o t a t i o n , 3. F i e ld o p e r a tio n s t o b e p erfo rm ed , 4. S t a r t i n g and f i n i s h i n g d a te c o n s t r a i n t s f o r each o p e ra tio n , 5. F i e ld work h o u rs p e r w orking day f o r each o p e ra tio n , 6. The d e s ir e d d e sig n p r o b a b i l i t y f o r m eetin g a l l d a te c o n s t r a i n ts and, 23 c START ) MAIN: Read in p u t d a ta and c a lc u ­ l a t e a re a f o r each f i e l d o p e ra ­ tio n , each cro p , and each implement INPUT DATA: Crop r o t a t i o n , farm s i z e , f i e l d work d a ta , s u i t a b l e tim e d a ta , m achine p r o d u c tiv ity d a ta , and m achine c o s t d a ta * CQMBINS: D eterm ine no. and s i z e o f SP combines 4- 1 Mfefltj?: C a lc u la te energy r e q u ir e 1 m ents o f each o p e ra tio n riHLTKS: D eterm ine no. and s i z e of t i l l a e e tra c to rs UTRCTRS: D eterm ine no. and s i z e of u t i l i t y tra c to rs ..................... * ATRCTRS: D eterm ine number o f a l f a l f a t r a c t o r s , i f re q u ire d REFTIME: C a lc u la te f i e l d tim e re q u ire d f o r each o p e ra tio n POWRUNT: Compare re q u ire d f i e l d tim e w ith a v a ila b le f i e l d tim e AVFTIME: C a lc u la te f i e l d tim e a v a ila b le w ith in s p e c if ie d d a te c o n s t r a i n ts a t s e le c te d d esig n p r o b a b ility le v e l I IMPUNTS: D eterm ine minimum r e ­ q u ire d no. o f u n i t s o f each implement______________ SCHDULE: P re p a re weekly o p e ra ­ t io n s sch ed u le f o r an 80% d esig n p r o b a b ility Yes — can a l l c o n s t r a i n ts be s a t i s f i e d ADJUSIM: In c re a s e s i z e o f t r a c ­ t o r s , implement u n i t s , o r r e d i s ­ t r i b u t e work among t r a c t o r c a te g o r ie s SCHDULE: P re p a re o p e ra tio n s sc h ed u le f o r an average y e a r SEQfTIAL: Schedule f i e l d o p e ra ­ t io n s which a re s t a r t e d a f t e r com pleting p re v io u s o p e ra tio n TTRACTR: Schedule f i e l d o p era­ tio n s a ssig n e d t o t i l l a g e 1t r a c ­ t o r s which a re c a r r i e d o u t a t same r a t e F llake equipm ent a s s ig n ment to each f i e l d o p e ra tio n ACEEH: C a lc u la te a re a h a rv e s te d o f th e p re v io u s cro p by end o f th e week MEANPH: C a lc u la te median comple­ t io n d a te o f p la n tin g /h a r v e s tin g F ig u re 3 .1 S im p lifie d G eneral Flow Diagram f o r M achinery System D esign. 24 2 IMPSIZE: S e le c t s iz e o f each implement A v a ila b le s iz e s of each implement 1 COST: C a lc u la te average annual m achinery, la b o r , and f u e l c o s ts F ig u re 3.1 ( co n t in u ed ) FUEL: C a lc u la te f u e l consump­ tio n f o r each f i e l d o p e ra tio n 25 7. Mean and sta n d a rd d e v ia tio n o f f r a c tio n o f s u ita b le days in each week o f th e y e a r f o r each ty p e o f o p e ra tio n . The in p u t d a ta used in t h i s stu d y i s given in Appendix A. 3 .1 .1 F ie ld work s p e c if ic a tio n s A ll f i e l d o p e ra tio n s were co n sid ered e x p l i c i t l y . T ra n s p o rta tio n , d ry in g , p ro c e ssin g , and farm stead o p e ra tio n s were not c o n sid ere d . However, t h e i r in flu e n c e can be r e f l e c t e d by a d ju s tin g working hours p e r s u i t a b l e working day. The f i e l d work d a ta used in t h i s stu d y i s shown in T able A .l (R obertson, 1977). 3 .1 .2 C alendar d a te s p e c if ic a tio n s f o r f i e l d work The c a le n d a r y e a r was d iv id e d in to 52 weeks in th e model. The c a le n d a r d a te c o n s tr a in ts which a re needed in th e model must be s p e c i­ f i e d in term s o f a weekly s t a r t i n g d a te a s given in Table A.2B; a s th e s u ita b le day d a ta was c a lc u la te d f o r th e s e weeks. C alendar d a te c o n s tr a in ts f o r th e p la n tin g and h a rv e s tin g o p e ra tio n s o f each cro p were s p e c if ie d based upon cropping p r a c tic e s r e p r e s e n ta tiv e o f so u th e rn M ichigan. They were so s e le c te d t h a t s a t i s f a c t i o n in 80 p e rc e n t o f a l l seaso n s was d e s ire d . F in is h in g d a te o f p r e p la n t t i l l a g e o p e ra tio n s was s p e c if ie d equal t o th e f in is h in g d a te c o n s tr a in t o f th e p la n tin g o p e ra tio n f o r t h a t cro p . I f a t i l l a g e operatic® was p e rm itte d in th e f a l l , i t s s t a r t i n g d a te c o n s tr a in t was s p e c if ie d equal t o t h e s t a r t i n g d a te c o n s tr a in t o f th e h a rv e s tin g o p e ra tio n o f th e p re ­ v io u s c ro p . But, i f a t i l l a g e o p e ra tio n was not p e rm itte d in f a l l , i t s s t a r t i n g d a te c o n s tr a in t was s e t equal t o th e e a r l i e s t sp rin g d a te on 26 which t i l l a g e o p e ra tio n s co u ld be s t a r t e d (A p ril 10, T able A.2B). F a ll t i l l a g e o p e ra tio n s , i f n o t com pleted in f a l l , were d is c o n tin u e d f o r th e p e rio d between November 27 and A p ril 9. D uring most y e a rs v ery l i t t l e , i f any, t i l l a g e can be done d u rin g t h i s p e rio d in so u th e rn M ichigan. I f a f i e l d o p e ra tio n was re q u ire d t o be done im m ediately p re c e d in g p la n tin g , i t s s t a r t i n g d a te c o n s t r a i n t was s p e c if ie d eq u al t o th e p la n tin g o p e ra tio n . S t a r ti n g and f i n is h in g d a te c o n s tr a in ts f o r cro p husbandry o p e ra tio n s t h a t a re perform ed in between p la n tin g and h a rv e s tin g were s p e c if ie d b ased on contem porary p r a c t ic e s o f th e re g io n . The f i e l d o p e ra tio n s w ere a rra n g e d s e q u e n tia lly in o rd e r o f de­ c re a s in g p r i o r i t y . d a te c o n s t r a i n t. The p r i o r i t y was a ssig n e d acc o rd in g t o th e f in is h in g The h a rv e s tin g o p e ra tio n which had th e e a r l i e s t f in is h in g d a te a f t e r June 30th was a ssig n e d th e h ig h e s t p r i o r i t y and was th e f i r s t o p e ra tio n in th e sequence. The f i e l d o p e ra tio n (h a rv e s t o r n o n -h a rv e st) which had a l a t e r b u t n e x t e a r l i e s t f i n is h in g d a te was a ssig n e d nex t h ig h e s t p r i o r i t y and so on. C alendar d a te c o n s t r a i n ts assumed in t h i s stu d y f o r each f i e l d o p e ra tio n a re shown in T able A .l (Lucas, 1976). F ie ld work d a ta and c a le n d a r d a te c o n s t r a i n ts f o r th e example farm a r e g iv en in T able 3 .1 which i s d e riv e d from T able A .l 3 .1 .3 la b o r p o lic y s p e c i f i c a ti o n s la b o r was assuned t o b e a v a ila b le t o o p e ra te a l l t r a c t o r s sim u l­ ta n e o u sly when h a rv e s tin g i s n o t in p r o g r e s s . H a rv e stin g o p e ra tio n s o fte n r e q u ir e a d d itio n a l h e lp f o r u n lo ad in g , h a u lin g , and p ro c e s s in g o f t h e c ro p h a rv e s te d , a s w e ll a s f o r th e o p e ra tio n o f th e h a r v e s te r . Some 27 T ab le 3 .1 F ie ld Work In p u t D ata f o r th e Example Farm. Crop r o t a t i o n = c o rn -co rn -so y b ean -w h eat Farm s i z e = 446 h e c ta r e s (1102 a c r e s ) D esign p r o b a b i l it y = 80 p e rc e n t Number o f t i l l a g e t r a c t o r s t o be i d le d f o r eac h h a r v e s te r o p e ra tin g in th e f i e l d =0 F i e ld o n e ra tio n o p e ra tio n H arv est wheat H arv est soybeans Moldboard plow f o r wheat D isk h arro w -d rag f o r wheat Seed d r i l l wheat H a rv e st c o rn a f t e r wheat H a rv e st c o m a f t e r c o m T b p dress n itro g e n on wheat Spray h e rb ic id e on wheat D isk f o r c o m a f t e r corn** S p read f e r t i l i z e r f o r c o m a f t e r w heat S pread f e r t i l i z e r f o r c o m a f t e r c o m M oldboard plow f o r c o m a f t e r w heat M oldboard plow f o r c o m a f t e r c o m D isk harrow f o r c o m a f t e r wheat D isk harrow f o r c o m a f t e r c o m P la n t c o m a f t e r w heat+ P la n t c o m a f t e r c o m D isk f o r soybeans** M oldboard plow f o r soybeans D isk harrow f o r soybeans P la n t soybeans4-1' Spray h e rb ic id e on soybeans Apply anraonia f o r c o m a f t e r wheat Apply anmonia f o r c o m a f t e r c o m How c u l t i v a t e c o m a f t e r wheat How c u l t i v a t e c o m a f t e r c o m How c u l t i v a t e soybeans * ** + ++ S t a r t i n g d a te Mo/Day 7/17 9 /18 9 /18 9 /1 8 9/18 10/09 10/09 3 /06 4 /1 7 10/09 4 /1 0 4 /1 0 4 /1 0 4 /1 0 4 /2 4 4 /2 4 4 /2 4 4 /2 4 10/09 4 /1 0 5 /15 5 /1 5 5 /15 5 /29 5 /29 6 /0 5 6 /0 5 6 /19 F in is h in g d a te * Ma/Day 8 /0 7 10/16 1 0/16 10/16 10/16 11/13 1 1/13 4 /0 3 5 /0 8 5/22 5/22 5/22 5 /2 2 5 /22 5 /22 5 /2 2 5 /2 2 5 /2 2 5 /2 8 5/28 5/28 5/28 6 /0 5 6 /2 6 6 /2 6 6 /2 6 6 /2 6 7 /0 3 The f i e l d o p e ra tio n m ust b e com pleted b e f o r e t h i s d a te . I f t h e f i e l d o p e ra tio n was n o t f i n is h e d d u rin g f a l l , i t was d i s ­ c o n tin u e d on Novenber 26 and was resum ed on A p ril 10 in t h e fo llo w in g s p r in g . H e rb ic id e s a p p lie d d u rin g th e p la n tin g o p e ra tio n . F e r t i l i z e r a p p lie d d u rin g th e p la n tin g o p e r a tio n . 28 t r a c t o r s may have to be fre e d from t i l l a g e o p e ra tio n s because la b o r may n o t be a v a ila b le f o r t i l l a g e o p e ra tio n s o r t r a c t o r s may be engaged in h a u lin g o p e ra tio n s . P ro v isio n was made in th e program whereby z e ro , one, o r two t r a c t o r s co u ld be id le d f o r each o p e ra tin g h a rv e s te r. In t h i s example no t i l l a g e t r a c t o r was id le d f o r each h a rv e s te r o p e ra tin g in th e f i e l d . S u f f ic ie n t a d d itio n a l la b o r and m achinery was assumed t o be a v a ila b le t o tr a n s p o r t h a rv e ste d crop to th e farm stead. Work on Sundays was n o t p e rm itte d b u t no o th e r h o lid a y s were co n sid ere d . The p r a c t ic e o f u sin g m achinery two s h i f t s p e r working day was a ls o n o t c o n sid e re d . F ie ld work hours p e r day f o r d i f f e r e n t ty p es o f o p e ra t ions t h a t were assumed in t h i s stu d y f o r so u th ern Michigan c o n d itio n s a re given in T able A.2A. These v a lu e s were s e le c te d to r e f l e c t ty p ic a l p r a c tic e s d u rin g th e peak work seaso n , as i t i s t h a t p e rio d which la r g e ly determ ines m achinery req u ire m e n ts. 3 .1 .4 Mean and sta n d a rd d e v ia tio n o f f r a c tio n o f s u i t a b l e days T u lu 's (1974) s u i t a b l e work days model was used t o c a lc u la te 2 0 -y ear d a ily s u i t a b l e day sequences f o r a l l n o n -h arv e st o p e ra tio n s and f o r c o m h a rv e s tin g from W eather Bureau re c o rd s (1953-1968 from D e tro it C ity A irp o rt and 1969-1972 from E ast L a n sin g ). T u lu 's co m combining c r i t e r i o n was used f o r sp ra y in g , f e r t i l i z e r sp re ad in g , c o rn s ta lk sh red d in g , and co rn h a rv e s tin g o p e ra tio n s . The t i l l a g e c r i t e r i o n was used f o r a l l f a l l and s p r in g t i l l a g e and p la n tin g o p e ra tio n s . The mean and sta n d a rd d e v ia tio n o f th e f r a c t io n o f c a le n d a r days s u ita b le f o r f i e l d work w ere c a lc u la te d f o r each week from th e s e sequences f o r each ty p e o f o p e ra tio n . The sequences o f c a lc u la te d mean and sta n d a rd d e v ia tio n were smoothed u sin g fo llo w in g eq u atio n : ^ i = where PS^ = smoothed v a lu e o f mean (o r sta n d a rd d e v ia tio n ) f o r th e week i . = a c tu a l v alue o f mean ( o r sta n d a rd d e v ia tio n ) f o r th e week i . The smoothed sequences a re shown in Table A.2B. The mean and sta n d a rd d e v ia tio n o f th e f r a c tio n o f s u i t a b l e work­ days f o r soybean, f i e l d bean, and wheat h a rv e s tin g were e stim a te d from a p e rso n a l can n o n ica tio n (Adams, 1975). A lf a lf a h a rv e s tin g s t a t i s t i c s w ere e stim a te d from d a ta given by M illie r and Rehkugler (1972). e s tim a te s a re d isp la y e d in T able A.2C. These T ables A.2B and A.2C were used as an exogeneous in p u t t o th e model. 3.2 H a rv este r S ize I t was assumed t h a t a l l h a rv e s tin g o p e ra tio n s , o th e r th an a l f a l f a h a rv e s tin g a r e dene by s e lf - p r o p e lle d combines. changeable heads w ere assumed. in th e model. U n its w ith i n t e r ­ Four s iz e s o f combines were p e rm itte d Assumed s i z e , speed, f i e l d e f f ic ie n c y , and e f f e c t i v e f i e l d c a p a c ity o f th e fo u r b a s ic s i z e s f o r th e v a rio u s h a rv e s tin g o p e ra tio n s a re given in T able A.3A. The methodology used f o r determ in in g number and s iz e o f combines i s shown in F ig u re 3.2 30 C S u b ro u tin e COMBINS ^ ____ 1 I S e le c t f i e l d o p e ra tio n s t o be done by SEP combines NC = 0 NC = NC + 1 1 No. o f caribines s i z e o f each 2-row combine: 1 1 1 2 2 3 4-row 6-row 8-row 6-row 3-row 8-row S u b ro u tin e REFTIME C a lc u la te f i e l d tim e re q u ire d f o r each o p e ra tio n HZ NS = 1 S u b ro u tin e POWKUNT (NS, JC) Check i f a l l d a te c o n s t r a i n ts can be s a t i s f i e d S u b ro u tin e AVFTIME C a lc u la te f i e l d tim e a v a ila b le w ith in s p e c if ie d d a te c o n s tra in l a t a giv en d esig n p r o b a b ility le v e l RETURN JC = 1 in d ic a te s t h a t a l l o p e ra tio n s have been com pleted w ith in s p e c if ie d d a te c o n s t r a i n ts , and JC = 0 in d ic a te s n o t. NS = 1 in d ic a te s t o th e s u b ro u tin e POWRUNT t o r e tu r n t o c a l l i n g s t a t e ­ ment i f a d a te c o n s t r a i n t i s v io la te d , and NS = 2 in d ic a te s to f i n i s h a s much a re a o f each o p e ra tio n a s p o s s ib le w ith th e given power u n i t . F ig u re 3 .2 . Flow Diagram f o r Combine S iz e S e le c tio n . 31 3 .3 T ra c to r S iz e T hree s i z e s o f tw o-w heel d r iv e t r a c t o r s m y ap p ea r in a s e l e c te d m achinery system . T h is o p tio n p ro v id e s f u l l u t i l i z a t i o n o f t r a c t o r power f o r m ost o p e r a tio n s . A ll p r e p la n t t i l l a g e o p e ra tio n s and n o - t i l l p l a n t i n g o p e ra tio n s a r e a s s ig n e d t o t i l l a g e t r a c t o r s o f e q u a l s i z e , w hich i s c o n s tr a in e d t o t h e ran g e o f 2 9 .8 PTD kW (40 HP) t o 1 1 1 .9 PTO kW (150 HP). The n irrb e r and s i z e o f t i l l a g e t r a c t o r s was d e te rm in e d by t h e p ro c e d u re o u tlin e d in F ig u re 3 .3 . The p ro c e d u re c o n ta in s a p r o v is io n (n o t shown i n F ig u re 3 .3 , t o keep t h e flow diagram s im p le ) , whereby a s many a s two t r a c t o r s can b e i d le d f o r each o p e r a tin g h a r v e s t e r . U t i l i t y t r a c t o r s o f e q u a l s i z e , in th e ran g e o f 2 2 .4 PTO kW (30 HP) t o 6 7 .1 PTO kW (90 HP), w ere u se d f o r a l l o t h e r f i e l d o p e r a tio n s . If p o s s ib le , t h e s e l e c t i o n p ro c e s s (F ig u re 3 .4 ) r e s t r i c t s t h e number o f u t i l i t y t r a c t o r s t o one by u s in g a v a ila b le t i l l a g e t r a c t o r s f o r th e s e o p e r a tio n s . However, u t i l i t y t r a c t o r s w ere n o t a s s ig n e d p r e p la n t t i l l a g e o p e ra tio n s t o supplem ent th e t i l l a g e t r a c t o r s . T h is k e ep s t h e re q u ir e d la b o r and number o f implement u n i t s t o minimum. A l f a l f a m o w in g -co n d itio n in g and b a lin g o p e ra tio n s w ere done by t r a c t o r s o f 2 9 .8 PTO kW (40 HP) s i z e , h e r e a f t e r c a l l e d a l f a l f a t r a c t o r s . The s e l e c t i o n p ro c e ss (F ig u re 3 .5 ) m inim izes t h e number o f a l f a l f a t r a c t o r s by u s in g a v a ila b le u t i l i t y and t i l l a g e t r a c t o r s f o r a l f a l f a h a r v e s tin g o p e ra tio n s , i f p o s s ib l e . However, a l f a l f a t r a c t o r s w ere u se d e x c lu s iv e ly f o r a l f a l f a h a r v e s tin g o p e r a tio n s . T illa g e t r a c t o r s w ere used f o r t h e o p e r a tio n s a s s ig n e d t o u t i l i t y t r a c t o r s o r a l f a l f a t r a c t o r s o n ly f o r t h e tim e f o r w hich th e y w ere f r e e from t h e o p e ra tio n s t o which th e y a r e n o im a lly a s s ig n e d . S im ila rly , 32 C S u b ro u tin e TTRCTRS I S e le c t f i e l d o p e r a tio n s t o be done by t i l l a g e t r a c t o r s SET: HPMAXT = 150.0 HPTRACT = 4 0 .0 HPENCT = 4 0 .0 E $ $ $ HPMINT = 4 0 .0 NTRACT = 1 NC = 1 $ NS = 1 S u b ro u tin e HEFTIME C a lc u la te f i e l d tim e r e q u ir e d f o r e ac h o p e r a tio n ] ------------------------------------- S u b ro u tin e POWRUNT (NS, JC) Check i f a l l d a te c o n s t r a i n t s c an b e s a t i s f i e d L S u b ro u tin e AVFTIME C a lc u la te f i e l d tim e a v a i l a b l e w ith in s p e c i f i e d d a te con­ s t r a i n t a t a g iv e n d e sig n p ro b a b ility le v e l NTRACT = NTRACT + 1 HPTRACT - HPMINT c m »{NG=NC + 1 w r ) =3 wmui' =,mnACT~"3o.m HPENCT « 1 0 .0 HPTRACT = HPTRACT + HPENCT No > HPMAXf HPTRACT = HPTRACT - 9 .0 HPENCT = 1 .0 Yes HPTRACT = HPMAXT HPTRACT = horsepow er o f e a c h t i l l a g e t r a c t o r NTRACT =number o f t i l l a g e t r a c t o r s HPENCT =horsepow er in cre m e n t f o r t i l l a g e t r a c t o r s i z e s e l e c t i o n HPMAXT =maximun horsepow er p e r m itte d f o r each t i l l a g e t r a c t o r HPMINT =minimum ho rsep o w er p e r m itte d f o r e ac h t i l l a g e t r a c t o r JC, NC =See F ig u re 3 .2 F ig u re 3 .3 . Flow Diagram f o r E s tim a tin g S iz e and Number o f T il l a g e T r a c to r s . 33 C S ubroutine U T R C T R S J i S e le c t f i d ops t o be perform ed by u t i l i t y t r a c t o r s SET: INITIALIZE: $ $ $ NTRACU = 1 NC = 0 HPMINU = 30.0 HPTRAC « HPTRAC1U $ HPENC = HPENCU NS = 1 $ NF = 1 ---------------- ► 0 i HPTRACU = 30 0 HPENCU = 10 0 HPMAXU = 90 0 i' NTRAC = NTRACU $ IT = 3 S ub ro u tin e REFTIME C a lc u la te f i e l d tim e re q u ire d f o r each o p e ra tio n E HPTRACU = HPTRAC © S ubroutine POWRUNT (NS, JC) Check i f a l l d a te c o n s tr a in ts can be s a t i s f i e d - S ubroutine AVFTIME C a lc u la te f i e l d tim e a v a i l ­ a b le w ith in s p e c if ie d d a te c o n s tr a in t a t a given design p r o b a b ility HFTRAC = HPTRACU NONC+1 « ---------M HPTRACU - horsepower o f each u t i l i t y t r a c t o r NTRACU = number o f u t i l i t y t r a c t o r s HPMAXU = maximum horsepower p e rm itte d f o r each u t i l i t y t r a c t o r HPMINU = minimum horsepower p e rm itte d f o r each u t i l i t y t r a c t o r HPENC = horsepower increm ent NS, JC = See F ig u re 3 .2 . F ig u re 3 .4 . S im p lifie d Flow Diagram fo r E stim a tin g S iz e and Number o f U t i l i t y T ra c to rs . 34 Yes = HPMAXU? No HPTRAC = HPMINU NTRACU=NTRAC+1 NS = 1 HPTRAC = HPTRAC + HPENC Yes HPTRAC = HPMAXU $ NS = 2 NONC+1 RETURN =1 HPTRAC = HPTRAC - 9 .0 HPENC = 1 . 0 =3 =2 HPTRACU = HPTRAC Yes, RETURN No .1 o p . fin is h e i Yes No IT = 2 HPTRAC = HPTRACT NTRAC = NTRACT C a lc u la te a re a l e f t and f i e l d tim e re q u ire d f o r each opera­ tio n ____________ F ig u re 3 .4 . (co n tin u ed ) NS=1 Yes 11 op. finish* 35 ( Subrout in e ATRCTRS S e le c t f i d ops t o b e perform ed by a l f a l f a t r a c t o r s SETT: HPTRACA = 4 0 .0 IT = 4 $ NTRACA = 1 S u b ro u tin e KEFTIME C a lc u la te f i d tim e re q u ire d f o r each o p e ra tio n S u b ro u tin e POWRUNT (NS, JC) Check i f a l l d a te c o n s t r a i n ts can be s a t i s f i e d S u b ro u tin e AVFTIME C a lc u la te f i d tim e a v a ila b le w ith in s p e c if ie d d a te con­ s t r a i n t a t a given d esig n p r o b a b ility RETORN ) D eterm ine rem aining a re a o f each o p e ra tio n =2 _— IT=4 NTRACA=NTRACA + 1 HFTRAOHPTRACA NTRAO^TIRACA ------- =3 IT=2 HPTOAOHPTRACT NTRAC=NTRACT C a lc u la te tim e r e ­ q u ire d to c a n p le te each rem aining op. =4 IT=3 HPTRAOHPTRACV NTRAC=NTRACU C a lc u la te tim e r e ­ q u ire d t o com plete each rem aining op. HPTRACA = horsepow er o f each a l f a l f a t r a c t o r NTRACA = nurrber o f a l f a l f a t r a c t o r s F ig u re 3 .5 S im p lifie d Flow Diagram f o r S e le c tin g Number o f A lf a lf a T r a c to r s . 36 u t i l i t y t r a c t o r s w ere u se d f o r a l f a l f a h a r v e s tin g o p e ra tio n o nly f o r th e tim e f o r which th e y w ere f r e e from th e o p e ra tio n s t o which th e y a r e n orm ally a s s ig n e d . The p ro ce d u re f o r a cco m p lish in g t h i s i s n o t shown in F ig u re s 3 .3 th ro u g h 3 .6 t o keep t h e flow diagram s s i n p l e . The p r i n c i p l e o f assignm ent o f work t o d i f f e r e n t s i z e s o f t r a c t o r s a c c o rd in g t o lo a d re q u ire m e n ts , which i s t h e b a s i s o f t h e above s e l e c t i o n p ro c e d u re , i s su p p o rte d by f i e l d o b s e r v a tio n s . Hunt (1972) n o te d in a sm a ll su rv e y t h a t fa rm e rs g e n e ra lly a s s ig n heavy d r a f t o p e ra tio n s t o b ig t r a c t o r s and u s e s m a lle r t r a c t o r s f o r l i g h t f i e l d work. T h is p ro c e d u re a ls o m inim izes t h e la b o r re q u ire m e n ts s in c e th e heavy t i l l a g e work i s a s s ig n e d t o b ig t r a c t o r s . 3 .4 A v a ila b le F i e ld Work Time A v a ila b le f i e l d work tim e f o r an o p e ra tio n depends ip o n th e c a le n d a r p e rio d s p e c i f i e d f o r i t , t h e f r a c t i o n o f c a le n d a r days s u i t a b l e f o r w ork, and fie ld -w o rk h o u rs p e r workday. The f r a c t i o n o f c a le n d a r days s u i t a b l e f o r work i s w e a th e r dependent and was c a lc u la te d on a p r o b a b i l i s t i c b a s is . A d e sig n p r o b a b i l i t y o f com p letio n was em ployed. S u ita b le workdays c a c lu a te d a t 80 p e rc e n t d e sig n p r o b a b i l it y can be i n t e r p r e t e d a s m eaning t h a t on t h e a v erag e th e c a lc u la te d workdays o r more would o c c u r i n 80 p e rc e n t o f a l l se a s o n s. Tb c o n p u te t h e f i e l d w orking h o u rs a v a i la b l e a t d e sig n p r o b a b i l i t y , i t was assumed t h a t t h e w eekly f r a c t i o n s o f c a le n d a r days s u i t a b l e f o r f i e l d work w ere n o rm ally d i s t r i b u t e d and t h a t s u c c e s s iv e weeks w ere s t a t i s t i c a l l y in d e p e n d e n t. Thus, th e f r a c t i o n o f c a le n d a r tim e s u i t a b l e 37 f o r work d u rin g N s u c c e s s iv e weeks was n o rm a lly d i s t r i b u t e d . The N-week f r a c t i o n p o p u la tio n mean and v a r ia n c e w ere t h e a r i t h m e t i c means o f th e w eekly means and v a r ia n c e s . The f r a c t i o n o f c a le n d a r days s u i t a b l e in t h e N-week p e r io d f o r t h e d e s ig n p r o b a b i l i t y was com puted and f o r w eekly s c h e d u lin g was tra n s fo rm e d b ack t o a w eekly b a s i s u s in g a p ro ­ p o r t i o n a l r a t i o ( f i r s t b ra c k e te d te rm i n e q u a tio n 2 ) . The fo rm u la u se d f o r th e s e c o m p u ta tio n s was: M “““ Ik = i —L i M i —L M i —f j s 2ik>1/ 2l* m * Hk w here H o u r ^ = f i e l d w orking h o u rs a v a i l a b l e d u rin g week i f o r t h e k t h o p e ra tio n ^ = mean o f f r a c t i o n o f c a le n d a r d a y s s u i t a b l e f o r f i e l d work d u rin g week i f o r t h e k t h o p e r a tio n s i k = sr^an<^ar<^ d e v ia tio n o f f r a c t i o n o f c a le n d a r d ay s s u i t a b l e f o r f i e l d work d u r in g week i f o r t h e k t h o p e r a tio n L = f i r s t week o f t h e p e rio d M - l a s t week o f t h e p e r io d ND = number o f c a le n d a r d ay s w ork i s p e r m itte d d u rin g t h e week = 6 = f i e l d w ork in g h o u rs p e r day f o r t h e k t h o p e r a tio n Za = a m m ber from t h e norm al c u m u la tiv e d i s t r i b u t i o n t a b l e c o rre sp o n d in g t o t h e d e sig n p r o b a b i l i t y l e v e l = 0 . 8 4 f o r d e sig n p r o b a b i l i t y o f 0 .8 I t i s known t h a t t h e a ssu rrp tio n o f n o rm a lity i s n o t v a l i d f o r p e r io d s o f one week (T u lu , 1973). However, a s t h e l e n g th o f t h e p e r io d i s 38 in c re a se d , th e p r o b a b ility d i s t r ib u t i o n o f weekly f r a c tio n o f s u ita b le working days approaches n o rm a lity . 3 .5 R equired F ie ld Work Time F ie ld tim e r e q u ire d f o r any o p e ra tio n depends upon th e energy r e ­ quirem ents o f th e o p e ra tio n , t r a c t o r power a v a ila b le to th e implement, c o n s tr a in ts on s iz e and speed o f th e implement, machine r e l i a b i l i t y and r e l a t i v e p r o d u c tiv ity o f th e machine under f i e l d c o n d itio n s. The assum ption was made t h a t th e energy re q u ire d p e r u n it a re a f o r a p a r t i c u l a r o p e ra tio n i s speed in v a r ia n t. T his i s no t g e n e ra lly t r u e . F or example energy consum ption f o r m oldboard plows in c re a s e s a s some power o f speed (A g ric u ltu ra l E ngineers Yearbook, 1977). However, i f machine speed i s r e s t r i c t e d t o a narrow ran g e , th e energy re q u ire d can be assumed to be speed in v a r ia n t. The average u n i t d r a f t v a lu e s t h a t were used in t h i s study a r e giv en in T able A.3B. These a re average u n it d r a f t v a lu e s e stim a te d f o r a w ell d ra in e d Miami-Conover loam s o i l and in c lu d e th e r o l l i n g r e s i s ­ ta n c e o f th e implement and t r a c t o r (W hite, 1975b). The energy re q u ir e ­ m ents o f PTD-operated implements w ere c o n v erted in to u n it d r a f t v a lu e s t o f a c i l i t a t e c a lc u la tio n s . Farm t r a c t o r power i s r a te d acco rd in g to th e maximum observed PID horsepow er, as determ ined by th e Nebraska T ra c to r T e s ts . A s ig n i f ic a n t p a r t o f t h i s power i s n o t a v a ila b le f o r implement use a t th e drawbar d u rin g f i e l d o p e ra tio n s . th e a x le . Some o f th e power i s l o s t in tra n s m iss io n to T ypical r a t i o o f PTO t o a x le pcwer i s 0.96 f o r t r a c t o r s w ith a g e a r-ty p e tra n sm issio n (Zoz, 1972). Power i s a ls o l o s t a t th e i n te r f a c e 39 between th e s o i l and th e t i r e . T ra c tiv e e ff ic ie n c y i s a m easure o f t h i s power lo s s and i s d e fin e d a s th e r a t i o o f draw bar power to a x le power. T ra c tiv e e ffic ie n c y v a lu e s o f 0 .7 5 f o r u n t i l l e d and 0 .6 fo r t i l l e d f i e l d work (A g ric u ltu ra l E ngineers Yearbook, 1969) were used in t h i s stu d y . Zoz (1972) has p re se n te d a more e la b o ra te method o f p r e d ic tin g t r a c t o r 's drawbar perform ance under v a rio u s f i e l d c o n d itio n s . The assuned t r a c t i v e e ff ic ie n c y v a lu e s can a ls o be deduced from h i s d a ta , l b reduce engine wear and t o p rovide c a p a c ity fo r v ary in g lo a d s and in e v ita b le o verload s i t u a t i o n s t h a t occu r in farm ing o p e ra tio n s , th e av erage lo ad should be l e s s th an th e maximum c a p a b ility . A lo a d f a c t o r (LFAC) o f 0 .8 was assumed in t h i s study (W hite, 1975a). The s iz e s o f implements which were c o n sid ered in t h i s study a re g iv en in T able A.4A. Only th o se implement s iz e s were co n sid ere d which were l i s t e d in th e A g ric u ltu ra l Whole Goods P r ic e L is t o f Deere and Coupany (1975) o r in th e O f f ic ia l Guide t o T ra c to rs and Farm Equipment (S p rin g 1976). Speed c o n s tr a in ts f o r v a rio u s o p e ra tio n s assumed in t h e stu d y a re p re se n te d in Table A.3B and were tak en from W hite (1975b) o r th e A g ric u ltu ra l E ngineers Yearbook (1977). Machine r e l i a b i l i t y i s a measure o f th e p e rc en ta g e o f f i e l d tim e d u rin g which th e machine i s in o p e ra tin g c o n d itio n . In t h i s stu d y r e l i a b i l i t y f o r each machine was assuned equal t o u n ity . F ie ld e f f ic ie n c y i s a measure o f th e r e l a t i v e p r o d u c tiv ity o f a m achine under f i e l d c o n d itio n s . Average v a lu e s o f f i e l d e ff ic ie n c y used in t h i s stu d y , s e le c te d frcm Bowers (1970) o r th e A g ric u ltu ra l E ng ineers Yearbook (1977), a r e given in Ih b le A.3B. Hie e f f e c t i v e f i e l d c a p a c ity (a re a worked p e r u n it o f f i e l d tim e) f o r each tra c to r-p o w e re d implement was computed frcm t r a c t o r power u sin g 40 th e fo llo w in g r e l a ti o n s h i p : EEC. = HPTElAC*0.96,rC E .*Ii’AC,^R E .*e./(D i /3 6 0 ) J J J «J j = 1,2,...N T IM P (3) ij where EPC. = e f f e c t i v e f i e l d c a p a c ity o f o p e ra tio n j (h a /h ) J HPTRAC = t r a c t o r PTO power (kW) TE. = t r a c t i v e e f f ic ie n c y f o r o p e ra tio n j ( f r a c ti o n ) LFAC = t h e r a t i o o f t r a c t o r power used in perfo im in g an o p e ra tio n t o r a te d power o f t r a c t o r (0 .8 0 ) RE. = r e l i a b i l i t y o f m achine f o r o p e ra tio n j ( f r a c ti o n ) J e . = f i e l d e f f ic ie n c y o f m achine f o r o p e ra tio n j ( f r a c t i o n ) J D. = u n i t d r a f t o f m achine f o r o p e ra tio n j (N/m) 3 NTIMP = number o f tra c to r-p c w e re d im plem ents 360 = (3600 s / h x 1000 W/kW)/10000 m2/h a A djustm ents w ere made i f s i z e and speed c o n s t r a i n ts on th e implement were v i o la t e d . I f EPC. was g r e a t e r th a n t h a t which could b e o b ta in e d w ith t h e b ig g e s t a v a ila b le s i z e o f implement a t th e maximum o p e ra tin g speed (EPCMAX. ) , i t was e q u ated t o EFCMAX.. J «J I f EPC. was l e s s th a n t h a t which co u ld b e o b ta in e d w ith th e s m a lle s t J a v a ila b le s i z e o f implement a t th e minimum o p e ra tin g speed (EPCMIN.), J t r a c t o r power was in c re a s e d u n t i l EPC. > EPCMIN.. J «J A f u r t h e r c o n s t r a i n t was p u t on e f f e c t i v e f i e l d c a p a c i ti e s o f row p l a n t e r and c u l t i v a t o r im plem ents by r e s t r i c t i n g t h e i r s iz e t o th e same i n te g e r m u ltip le o f co rn head s i z e . The f i e l d tim e re q u ire d f o r an o p e ra tio n was c a lc u la te d by d iv id in g t h e a re a t o b e worked by th e e f f e c t i v e f i e l d c a p a c ity o f th e o p e ra tio n . 41 3 .6 Methodology f o r D eterm ining T ra c to r and Combine S iz e The e s s e n t i a l m ethodology f o r d e te rm in in g number and s i z e o f co m bines, t i l l a g e t r a c t o r s , u t i l i t y t r a c t o r s and a l f a l f a t r a c t o r s , h e r e a f t e r c a l l e d power u n i t s , i s a s fo llo w s: A power u n i t s i z e i s s e l e c te d and f i e l d tim e r e q u ir e d f o r each o p e ra tio n i s computed. R eq u ired f i e l d tim e (KFT) i s compared w ith a v a i la b l e f i e l d tim e (ATT). The p ro c e d u re f o r com paring RFT w ith APT i s c o n ta in e d in th e s u b ro u tin e PCWEUOT whose s im p lif ie d flow diagram i s shown in F ig u re 3 .6 . I f th e re i s any d if f e r e n c e betw een RFT and AFT, th e power u n i t s i z e i s a d ju s te d . The s m a lle s t power u n i t t h a t makes RFT £ AFT i s s e l e c te d . The s u b ro u tin e PCWHUNT i s c a l l e d f o r one ty p e o f power u n i t a t a tim e . A ll u n i t s o f one ty p e sh o u ld be o f th e same s i z e . The s e l e c ti o n p ro c e d u re assum es t h a t none o f th e t r a c t o r s would be i d le d due t o th e u n a v a i l a b i l i t y o f an implement u n i t . T h e re fo re , a l l u n i t s o f one ty p e work s im u lta n e o u s ly on one o p e ra tio n a t a g iv en tim e . O p e ra tio n s a r e sc h e d u le d a c c o rd in g t o th e f i n i s h i n g d a te p r i o r i t y e s t a b l is h e d in th e in p u t d a ta . However, a low er p r i o r i t y o p e ra tio n can b e sc h e d u le d in a week in w hich i t i s n o t p o s s ib le t o sc h e d u le any h ig h e r p r i o r i t y o p e ra tio n . The s e l e c t i o n p ro c e d u re a s s u r e s t h a t th e number o f power u n i t s o f s e l e c te d s i z e o f each ty p e a r e a b le t o f i n i s h th e f i e l d o p e r a tio n s a s s ig n e d t o t h a t ty p e o f pcwer u n i t w ith in th e s p e c i f i e d c a le n d a r d a te c o n s t r a i n t s , in d iv id u a lly a s w e ll a s c o l l e c t i v e l y , a t t h e s p e c i f i e d d e sig n p r o b a b i l i t y l e v e l . 42 ( " S u b r o u tin e PCWHUNT (NS, JC) CP=1 $ FCP=OP I $ ) JB=1 WEEK = s t a r t i n g week c o n s t r a i n t o f OP INITIALIZE: STAKIW = s t a r t i n g week c o n s t r a i n t o f QP ENDW = e n d in g week c o n s t r a i n t o f CP K = i n d e n t i f i c a t io n number f o r th e sequence o f w eekly mean and s ta n d a r d d e v ia tio n o f s u i t a b l e w orkdays f o r QP S u b ro u tin e AVFTIME C a lc u la te a v a i l a b l e f i e l d w orktim e in each week betw een STAKIW and ENDW f o r workday seq u en ce K C a lc u la te a r e a o f CP f i n i s h e d d u rin g t h e WEEK WEEK = WEEK + 1 > ENDW C a lc u la te unused f r a c t i o n o f th e WEEK T NS=? _ JC=0 OP = CP + 1 _ _ _ _ _ _ IK RETURNMI Y es j p i No WEEK F ig u r e 3 .6 S im p lif ie d Flow Diagram f o r t h e S u b ro u tin e POWRUNT 43 =1 JB=? ’ART(OP) < STARTW Yes =2 KP=OP STARTW = ENDW = K= CP = WEEK = START(GP) END(QP) WDS(POP) POP START(OP) ENDW = K= OP = WEEK = END(OP) WDS(QP) POP START(OP) M D No Yes (OP) > ENDW No No WDS(OP) = K? K = WDS(QP) es MK=? =1 MK=? =0 =0 OP START(OP) END(OP) WDS(OP) = = = = PGP = N= JB = MK = F ig u re 3 .6 . o p e ra tio n s t a r t i n g week c o n s t r a i n t o f OP e n d in g week c o n s t r a i n t o f QP i d e n t i f i c a t i o n number f o r t h e seq u en ce o f w eekly mean and s ta n d a r d d e v ia tio n o f s u i t a b l e w orkdays f o r CP f i r s t o p e r a tio n o f a seq u en ce o f o p e r a tio n s w hich a r e p e r ­ form ed w ith o u t any tim e gap in betw een nunber o f o p e r a tio n s 2 i n d i c a t e s t h a t f i e l d work i s b e in g s t a r t e d a f t e r a tim e gap, and JB = 1 i n d i c a t e s f i e l d work i s c o n tin u o u s 1 i n d i c a t e s t h a t a low er p r i o r i t y o p e r a tio n i s b e in g p erfo rm ed w h ile a h ig h e r p r i o r i t y o p e r a tio n c an n o t be s c h e d u le d , and MK = 0 i n d i c a t e s t h a t o p e r a tio n s a r e b e in g p erfo rm ed a c c o rd in g t o th e e s t a b l is h e d p r i o r i t y . ( c o n tin u e d ) 44 SOPOP CP-N Yes p a r t (^ 1 .0 ) o f th e week was not used JN ° No JB=2 be scheduled d u rin g th e WEEK Yes MK=1 C a ll S ubroutine AVPTIME C a lc u la te a re a o f CP f in is h e d d u rin g th e WEEK C a lc u la te unused f r a c tio n o f th e WEEK es WEEK = WEEK + 1 OP = SOP No Can CP — be scheduled d u rin g —_ th e WEEK ^ Yes F ig u re 3 .6 . ( c o n tin u e d ) )P co n p le te d 45 3 .7 Implorient S iz e and Number The s m a lle s t a v a ila b le implement which maximized t r a c t o r power u t i l i z a t i o n s u b je c t t o th e speed c o n s t r a i n ts was s e le c te d . The number o f u n i t s o f each implement was i n i t i a l l y e s tim a te d assum ing t h a t none o f them would be id le d due t o th e u n a v a i la b i li t y o f a t r a c t o r . The minimum number o f u n i t s o f each implement which co u ld f i n i s h a l l f i e l d o p e ra tio n s a ssig n e d t o th e im plem ent, w ith in th e s p e c if ie d d a te c o n s t r a i n ts a t d e sig n p r o b a b i l it y l e v e l , w ere s e le c te d . T h is sim p le p ro ced u re does n o t g u a ra n te e t h a t implement u n i t s so determ ined would be adequate f o r a p ro p e r o p e ra tio n s sc h e d u le . R ath er, i t p ro v id e s a low er bound on th e number o f u n i t s re q u ire d . The re q u ire d number o f u n i t s were e s ta b lis h e d when th e e x is te n c e o f a f e a s i b l e o p e ra tio n s sc h ed u le was d em o n strated . T able 3 .2 shows th e m achinery s e t s e le c te d and annual m achine u se f a r th e ex an p le farm (T able 3 .1 ) . 3 .8 O p e ratio n s Schedule The o p e ra tio n s sch ed u le i s a summary o f a c t i v i t i e s f o r each week b eg in n in g w ith th e f i r s t h a rv e s tin g o p e ra tio n a f t e r June 3 0 th . An o p e ra tio n s sc h e d u le computed f o r th e d e sig n p r o b a b ility was p re p a re d to d e te rm in e i f th e s e le c te d m achinery system was s u f f i c i e n t t o s a t i s f y a l l d a te c o n s t r a i n ts . In p re p a rin g o p e ra tio n s sc h e d u le , two m ethods were used t o d i s t r i ­ b u te t o t a l w eekly work tim e o f each power u n it among f i e l d o p e ra tio n s . 46 T ab le 3 .2 F ie ld M achinery S et S e le c te d and Annual Machine Use f o r th e Example Farm. Si?.e Machine F ie ld c a p a c ity (h a /h -u n it) Annual u se (h /u n it) Two t i l l a g e t r a c t o r s 9 0 .2 PTO kW 274 U tility tra c to r 5 3 .7 PTO kW 496 SP combine 8-rcw+ 263 Corn head 8-row ^ 1 .6 2 138 G rain head 4 .9 m 1 .6 6 + 125 Two m oldboard plows 5 -0 .4 1 m bottom 1.28 174 D isc harrow 5 .2 m 3.11++ 200 G rain d r i l l 4 .0 m 2 .3 9 47 P l a n te r 8-row ^ 2 .3 8 141 Ammonia a p p lic a to r 6-row+ 2 .3 6 94 Bow c u l t i v a t o r 8-row + 3 .2 5 103 Spin s p re a d e r 12.2 6 .8 7 49 S p ray er 6 .1 m** 3 .5 3 63 ♦How w id th = 0 .7 6 m ♦♦Width covered in one p a s s +Fi e l d c a p a c ity f o r w heat h a r v e s tin g = 1 . 9 2 (h a /h ) ++F ie ld c a p a c ity f o r c o rn s t a l k d is c in g = 4 .3 6 ( h a /h ) , and f o r d is c in g w ith d ra g a tta c h e d = 2 .7 2 (h a /h ) 47 H ie t o t a l w eekly work tim e o f a l l t i l l a g e t r a c t o r s was d i s t r i b u t e d among a l l p r e p la n t t i l l a g e o p e r a tio n s o f a c ro p in su ch a m anner t h a t by t h e end o f t h e week c u m u la tiv e a r e a com pleted o f e ac h o p e r a tio n was t h e sam e, a s f a r a s f e a s i b l e w ith a v a i la b l e equipm ent (S e c tio n 3 . 8 . 2 ) . F o r a l f a l f a h a r v e s t i n g , t h e t r a c t o r tim e was a l l o c a t e d betw een now ingc o n d itio n in g an d b a li n g o p e r a tio n s in such a m anner t h a t b o th o p e r a tio n s w ere c a r r i e d o u t a t i d e n t i c a l r a t e s . F o r a l l o t h e r o p e r a tio n s , th e power u n i t tim e was d i s t r i b u t e d among o p e r a tio n s s e q u e n t i a l l y . S ta rtin g w ith t h e h ig h e s t p r i o r i t y o p e r a t io n , a s much o f t h e t o t a l a v a i l a b l e w eekly work tim e o f t h e a p p r o p r ia te power u n i t was a ll o c a t e d t o t h e o p e r a tio n a s r e q u i r e d t o f i n i s h t h e o p e r a tio n (S e c tio n 3 . 8 . 1 ) . O p e ra tio n s w ere sc h e d u le d on a w eekly b a s i s a c c o rd in g t o th e p r i o r i t y e s t a b l i s h e d i n t h e in p u t d a ta . The g e n e r a l p ro c e d u re u se d f o r p r e p a r in g an o p e r a t io n s sc h e d u le was a s fo llo w s : t h e f i e l d o p e r a tio n s t h a t c o u ld b e sc h e d u le d d u r in g t h e week b a se d on c a le n d a r d a te c o n s t r a i n t s w ere s e l e c t e d . From among th e s e o p e r a tio n s , f i e l d o p e r a tio n s a s s ig n e d t o SP contoines w ere s e l e c t e d and sc h e d u le d s e q u e n t i a l l y (S e c tio n 3 . 8 . 1 ) . F i e l d o p e r a tio n s a s s ig n e d t o a l f a l f a t r a c t o r s w ere s e l e c t e d an d sc h e d u le d s e q u e n tia lly . Then a l l o t h e r o p e r a tio n s w ere sc h e d u le d a s f o llo w s : frcm among t h e c ro p s whose f i e l d o p e r a tio n s c o u ld b e sc h e d u le d d u rin g t h e week, t h e c ro p c o rre s p o n d in g t o t h e h ig h e s t p r i o r i t y n o n - h a r v e s tin g o p e r a tio n was s e l e c t e d . The n o n - h a rv e s tin g f i e l d o p e r a tio n s o f t h a t c ro p w hich c o u ld b e sc h e d u le d d u rin g t h e week w ere ch o sen . S t a r t i n g from t h e f i r s t o p e r a t io n , e a c h o p e r a tio n was checked t o s e e i f i t was a p r e p l a n t t i l l a g e o p e r a tio n . I f i t w as, th e n a l l p r e ­ p l a n t t i l l a g e o p e r a t io n s o f t h i s c ro p w ere s e l e c t e d and sc h e d u le d s im u lta n e o u s ly ( S e c tio n 3 . 8 . 2 ) . s c h e d u le d s e q u e n t i a l l y . But i f i t was n o t , th e n i t was When a l l t h e o p e r a tio n s o f a c ro p had been 48 scheduled, th e next crop was tak en and th e p rocedure was re p e a te d u n t i l a l l cro p s had been c o n sid ered . A sch ed u le f o r th e week was p r in te d . A check was made f o r v io la tio n o f th e c o n p le tio n d a te c o n s tr a in t f o r each o p e ra tio n a t th e end o f each week. I f a v io la tio n o ccu rred , an adjustm ent was made in th e nuntoer o f implement u n i ts o r t r a c t o r power, o r th e work was r e d i s tr i b u te d among th e th r e e ty p e s o f t r a c t o r s (S e ctio n 3 .8 .4 ) . I f no v io la tio n o ccu rred , th e nex t week was tak en and th e whole p ro cedure was re p e a te d u n t i l a l l weeks had been co n sid ered . Table 3.3A shows th e o p e ra tio n s sch ed u le f o r two weeks f o r th e example farm . T able 3.3B d e p ic ts th e a s s o c ia te d equipment assignm ents f o r th o s e weeks. 82.03 h e c ta re s o f moldboard plow ing f o r corn a f t e r wheat had been c o n p le te d b e fo re th e week o f A p ril 24. D isc harrow ing and p la n tin g o p e ra tio n s were s t a r t e d in th e week o f A p ril 24. An attem p t was made d u rin g th e week o f A p ril 24 t o make th e cum ulative a re a c o n p le te d o f d is c harrow ing o p e ra tio n eq u al t o t h a t o f moldboard plow ing o p e ra tio n . However, s in c e o nly one d is c harrow was a v a ila b le , only one t i l l a g e t r a c t o r co u ld be u t i l i z e d f o r d is c harrow ing and th e o th e r t i l l a g e t r a c t o r was used f o r moldboard plow ing. But i t was p o s s ib le in th e nex t week t o a ll o c a t e th e t i l l a g e t r a c t o r tim e between moldboard plow ing and d is c harrow ing in such a manner t h a t cum ulative a re a co n p leted o f each o p e ra tio n became th e same. Table 3 .4 shows a sinm ary o f o p e ra tio n s sch ed u le f o r th e whole y e a r f o r th e exanple farm . The computer program a ls o p re p a re s a sinm ary o f machine schedule f o r th e whole y e a r. An o p e ra tio n s sch ed u le was a ls o p rep a red f o r an "average" y e a r (50 p e rc e n t p r o b a b ility le v e l) u sin g th e p ro ced u re o u tlin e d above. 49 T able 3.3A O p eratio n s Schedule f o r th e Weeks o f A p ril 24 and May. 1 f o r th e Example Farm. Hours worked O peration H ectares co n p leted C unulative h e c ta re s co n p le te d A v a ila b le work hours* For th e week o f A p ril 24 Oom a f t e r wheat Moldboard plow D isc harrow P la n t 21.2 2 1.2 23.0 T o ta l f i e l d work hours 27.15 65.93 54.64 109.18 65.93 54.64 21.2 21.2 23.0 65.4 F or th e week o f May 1 Oom a f t e r wheat Moldboard plow D isc harrow P la n t 1.8 14.6 23.9 2.31 45.56 56.85 111.50 111.50 111.50 27.4 27.4 2 9 .7 Com a f t e r com Moldboard plow D isc harrow P la n t 27.2 11.2 5 .8 34.83 34.83 13.85 34.83 34.83 13.85 27.4 27 .4 29.7 T o ta l f i e l d work hours 84.5 ♦ A v ailable f i e l d work tim e p e r u n i t machine d uring th e week, c a lc u la te d by e q u a tio n ( 2 ) . Table 3.3B Machine Schedule for the Weeks o f A pril 24 and May 1 fo r the Example Farm. Power U nit Implement T illa g e T ra c to r #1 Hours worked H ectares co npleted T illa g e T ra c to r #2 Hours worked H ectares co n p le te d U t i l i t y T ra c to r #1 Hours worked H ectares co n p leted 0 .0 0 .0 23.0 0 .0 0 .0 54.64 For th e week o f A p ril 24 Corn a f t e r wheat Moldboard plow D isc harrow P la n te r T o ta l f i e l d work hours 21.2 0 .0 0 .0 27.15 0 .0 0 .0 21.2 0 .0 21.2 0 .0 0 .0 65.93 0 .0 21.2 23.0 For th e week o f May 1 Corn a f t e r wheat Moldboard plow D isc harrow P la n te r 1.8 14.6 0 .0 2.31 45.56 0 .0 0 .0 0 .0 0 .0 0 .0 0 .0 0 .0 0 .0 0 .0 23.9 0 .0 0 .0 56.85 Com a f t e r corn Moldboard plow D isc harrcw P la n te r 11.0 0 .0 0 .0 14.04 0 .0 0 .0 16.2 11.2 0 .0 20.80 34.83 0 .0 0 .0 0 .0 5 .8 0 .0 0 .0 13.85 T o ta l f i e l d work hours 27.4 27.4 29.7 T a b le 3 .4 S ir n o r y o f O p o r a t h n s S c h e d u le f o r th e R u m p le Fartn ( h e c t a r e s c m p l o t e d o f e a c h o p e r a tio n lit eac h w eek ). 0|»? r a tio n ( b r n a f t e r w heat H arv est S pread f e r t i l i z e r ll"ildhonrd plow Disc. Imrrow P la n t A ip ly um iim ln Dow c u l t i v a t e d im a f lo r com H arv est D isc S p read f e r t i l i z e r H ddlicuird plow D isc harrow P la n t Apt>ly onniHila Bow c u l1 1v a le 10 A p ril W "2? 5B IS 52 29 ro Jiwe 12 19 "55 J u ly r r i r — si S c p tc n te r Iff 55' 02 09 3 8 .7 111 .5 4 2 .2 O c to b er 16 23 5 1.4 Nov 30 18.4 ffi 11.1 a I 111. r. 111.5 3 0 .8 2 7 .2 6 5 .9 5 4 .6 2 .3 4 5 .6 5 6 .9 li i . r, II 1.5 9 1 .4 iii.fi 17.1 111.5 111.5 111.5 cn 3 8 .7 54.4 3 1 .7 18.4 4 4 .0 111.5 3 4 .8 3 4 .8 13.8 5 7 .3 5 7 .3 7 8 .3 1 9 .4 19.4 19.4 2 .4 9 8 .5 Soybeans H a rv est D isc U d tlx N trd plow Dl sc ha.rna* 10.6 111 .5 3 3 .6 3 3 .5 1 0 .8 111. 3 1 .7 4 4 .7 4 4 .7 4 4 .7 4 4 .7 Spray lie r h i c l d c s ftiw c u l t l v a t e 6 0 .8 6 3 .8 6 0 .8 5 6 .7 4 4 .9 3 1 .9 111. 111. 111. 111. 10.1 ill. Ill. 1 1 .8 9 9 .7 3 7 .2 3 7 .2 3 7.1 3 3 .6 3 3 .6 3 3 .6 111.5 3 1 .9 111.5 111.5 111.5 111.5 111.5 111.5 111. 5 111.5 3 3 .6 Plant Wheat lla rv p st l li h l x x ir d plow Disc, h a rro w -d ra g S>ed d r i l l T o p d ress n itr o g e n S|irny h e r b ic id e Hay 51 3 3 .6 3 3 .6 3 3 .6 3 3 .5 3 3 .5 3 3 .5 1 0 .8 1 0 .8 10.8 111.5 111.5 111 .5 111.5 111.5 H 1.5 52 I t se rv e d t o determ ine th e la b o r d i s t r i b u t i o n d u rin g th e y e a r. Median corqpletion d a te s f o r h a rv e s tin g and p la n tin g o p e ra tio n s o f each crop were c a lc u la te d from t h i s o p e ra tio n s sch ed u le (Appendix B) to p ro v id e an in d ic a tio n o f th e tim e lin e s s c o s t inv o lv ed w ith th e s e le c te d m achinery s e t . T able 3 .5 d e p ic ts median com pletion d a te s f o r h a rv e s tin g and p la n tin g o p e ra tio n s f o r th e example farm . T able 3 .5 Median Completion D ates f o r H arv estin g and P la n tin g f o r t h e Example F a m ( a t 50 p e rc e n t p r o b a b ility l e v e l) . Crop H arv estin g P la n tin g Cbrn a f t e r wheat 1 0 /0 9 1 + 7 .I 2 4 /2 4 1 + 9 .9 2 Corn a f t e r co m 10/09 + 20.0 4 /24 + 13.0 Soybeans 9 /18 + 1 0 .8 5/15 + 4 .7 Wheat 7/17 + 1 0 .4 9/18 + 1 0 .8 P a r t i n g d a te c o n s tr a in t (m onth/day) 2Days a f t e r s t a r t i n g d a te c o n s tr a in t 3 .8 .1 S cheduling o f n o n - tilla g e o p e ra tio n s A ll f i e l d o p e ra tio n s , o th e r th a n p re p la n t t i l l a g e o p e ra tio n s , were sch eduled s e q u e n tia lly in each week acco rd in g t o th e p r i o r i t y e s ta b lis h e d in th e in p u t d a ta . S ta r tin g from th e h ig h e s t p r i o r i t y o p e ra tio n , th e maximm a re a o f each o p e ra tio n t h a t co u ld b e f in is h e d d u rin g th e week, s u b je c t t o c e r ta in c o n s tr a in ts , was c a lc u la te d and equipment assignm ent was made (S e c tio n 3 .8 .3 ) . The a re a o f an o p e ra tio n t h a t co u ld be fin is h e d d u rin g a week by a ty p e o f power u n i t was c o n stra in e d such t h a t : 1. The cum ulative area* co n p le te d o f th e o p e ra tio n does not exceed a. b. ACRECFP - th e cum ulative a re a co n p leted o f a p rev io u s n o n -h arv e stin g o p e ra tio n o f th e same cro p , i f th e r e i s any ACHECFH - th e cum ulative a re a co n p leted o f a h a rv e stin g o p e ra tio n o f th e p rev io u s cro p , i f th e r e i s any. 2. The cum ulative a re a c o n p le te d o f th e o p e ra tio n by th e ty p e o f power u n it does no t exceed th e t o t a l a re a o f th e o p e ra tio n a ssig n e d to t h a t type o f power u n i t. 3. T o ta l tim e o f th e ty p e o f power u n it used f o r th e o p e ra tio n does n o t exceed th e t o t a l a v a ila b le f r e e tim e o f th a t ty p e o f power u n it f o r th e week. 4. T o ta l tim e o f th e re q u ire d implement u n i ts used f o r th e o p e ra tio n does n o t exceed th e t o t a l a v a ila b le f r e e tim e o f th e implement u n its fo r th e week. 3 .8 .2 Scheduling o f t i l l a g e o p e ra tio n s A ll p re p la n t t i l l a g e o p e ra tio n s o f a crop were c a r r ie d o u t in th e p ro p er sequence a t r a t e s which produced lan d f i t f o r p la n tin g a s e a r ly a s p o s s ib le based on a v a ila b le equipm ent. I b i s was acoonplished by a llo c a tin g t i l l a g e t r a c t o r tim e among th e s e o p e ra tio n s in two s te p s . In th e f i r s t s te p , c u n u la tiv e a re a (ACKECF) t o which a l l p re p la n t o p e ra tio n s o f a cro p could be c a r r ie d o u t by th e end o f th e week, s u b je c t t o c e r ta in c o n s tr a in ts , was determ ined. The t o t a l weekly work tim e o f a l l t i l l a g e t r a c t o r s was a llo c a te d among th e s e o p e ra tio n s so as ♦C unulative a re a c o n p le te d o f an o p e ra tio n r e f e r s t o th e t o t a l a re a o f th e o p e ra tio n f in is h e d from th e s t a r t o f th e o p e ra tio n to th e end o f th e week. 54 t o b r in g c o n p le te d cum ulative a re a o f each o f th e s e o p e r a tio n s e q u a l to ACRECF. In th e second s te p , th e t i l l a g e t r a c t o r tim e l e f t , i f any, was a llo c a te d among p re p la n t t i l l a g e o p e ra tio n s o f t h i s cro p \asing th e p ro ce d u re f o r s e q u e n tia l o p e ra tio n s (S e c tio n 3 ,8 ,1 ) . The whole p ro ced u re was re p e a te d f o r th e n ex t crop to a l l o c a t e any rem aining t i l l a g e t r a c t o r tim e. ACRECF was c o n s tra in e d by: 1 . ACRECFP, 2 . ACRECFH, 3. S h o rte s t a v a ila b le f r e e tim e f o r any o f th e implement which i s re q u ire d f o r th e p re p la n t t i l l a g e o p e ra tio n s o f th e c ro p , 4. A v a ila b le f r e e tim e o f th e t i l l a g e t r a c t o r s , and 5. S m a lle st t o t a l a re a a ssig n e d t o t i l l a g e t r a c t o r s o f any o f t h e p re p la n t t i l l a g e o p e ra tio n o f th e c ro p . 3 .8 .3 Equipment assignm ent A fte r d e te rm in in g th e a re a o f an o p e ra tio n t h a t co u ld b e f in is h e d d u rin g t h e week, equipm ent assignm ent was made. The a re a was f i r s t a ssig n e d t o each a p p ro p ria te power u n i t and th en t o each u n i t o f th e re q u ire d im plem ent. The same p ro ced u re was used t o a s s ig n a re a t o power u n i t s o r t o implement u n i t s . S t a r ti n g w ith t h e f i r s t u n i t , a s much a re a was a ssig n e d t o each u n i t a s p o s s ib le . The a re a a ssig n e d t o each u n i t was c o n s tra in e d by: 1. The a re a o f th e o p e ra tio n t h a t i s u n assig n ed t o a u n i t 2 . The a re a t h a t th e u n i t can com plete d u rin g th e week in th e a v a ila b le f r e e tim e . 55 3 .8 .4 A djustm ents made, i f s e l e c te d m achinery s e t was in a d e q u a te f o r a r e a l i s t i c sc h e d u le A check was made f o r t h e v i o l a t i o n o f th e com pletion d a te c o n s t r a i n t f o r each o p e ra tio n a t th e end o f each week. Whenever a v i o l a t i o n f o r an o p e ra tio n o c c u rre d , an a d ju stm e n t was made in t h e nunber o f u n i t s o f th e implement w hich was u se d f o r th e o p e r a tio n , o r in power o f th e t r a c t o r ( s ) t o which t h e o p e ra tio n was a s s ig n e d . Ib e a d ju stm en t was b a sed upon th e t r a c t o r c a te g o ry t o w hich th e o p e ra tio n was a s s ig n e d . If t h e o p e ra tio n was a s s ig n e d t o t i l l a g e t r a c t o r s and i f th e number o f u n i t s o f th e in p lem en t w ere l e s s th a n th e nunber o f t i l l a g e t r a c t o r s , number o f in plem ent u n i t s was in c r e a s e d by one ( s e e 1 b e lo w ). But i f t h e number o f u n i t s o f t h e in p le m en t w ere e q u a l t o number o f t i l l a g e t r a c t o r s , t i l l a g e t r a c t o r power was in c re a s e d ( s e e 3 b e lo w ). I f th e o p e ra tio n was a ssig n e d t o u t i l i t y t r a c t o r s , i t was determ in ed w h eth er a l l u n i t s o f th e in plem ent w ere engaged f o r t h e w hole week. I f s o , i t was th e n assumed t h a t th e number o f u n i t s o f t h i s in p lem en t was i n s u f f i c i e n t and was in c re a s e d by o n e ( s e e 1 b e lo w ). However, i f t h e number o f u n i t s o f t h i s in p lem en t was e q u a l t o n u n b er o f u t i l i t y t r a c t o r s , o r i f a l l u n i t s o f t h e implement w ere n o t busy f o r th e w hole week, u t i l i t y t r a c t o r s i z e was in c r e a s e d (s e e 2 b e lc w ). I f t h e o p e ra tio n was a s s ig n e d t o b o th c a te g o r ie s o f t r a c t o r s , u t i l i t y and t i l l a g e , a check was made w h eth er u t i l i t y t r a c t o r s had f i n is h e d t h e i r s h a r e o f w ork. I f so, nunber o f u n i t s o f t h e implement was in c r e a s e d by one, s u b je c t t o th e u p p e r c o n s tr a in t e q u a l t o t h e sum o f u t i l i t y and t i l l a g e t r a c t o r s . O th erw ise, th e p ro c e d u re f o r o p e r a tio n s a s s ig n e d t o u t i l i t y t r a c t o r s was re p e a te d . A v i o la t io n may o c c u r b ecau se: 1. The number o f in plem ent u n i t s i s in a d e q u a te : The t r a c t o r s may be fo rc e d t o rem ain i d l e b ecau se o f th e u n a v a i l a b i l i t y o f an in plem ent u n i t . To c o r r e c t th e problem , t h e program in c r e a s e s t h e nunber o f u n i t s o f t h e in plem ent c o rre sp o n d in g t o t h e o p e ra tio n f o r which v i o l a t i o n o c c u rre d by o ne, s u b je c t t o th e u p p er c o n s t r a i n t e q u al t o t h e nunber o f c o rre sp o n d in g tra c to rs . The o p e ra tio n s sc h e d u le i s th e n p re p a re d a g a in from t h e b e g in n in g . 2. U t i l i t y t r a c t o r ( s ) i s fo rc e d t o rem ain i d l e : U tility tra c to r(s ) may be fo rc e d t o rem ain i d l e f o r p a r t o f t h e tim e i f p r e p la n t t i l l a g e o p e ra tio n s can n o t be perform ed a t a r a t e t h a t e n a b le s t h e u t i l i t y t r a c t o r ( s ) t o work f u l l tim e . T h is may r e s u l t in v i o l a t i o n o f t h e co m pletion d a te c o n s t r a i n t f o r o p e r a tio n s a s s ig n e d t o t h e u t i l i t y t r a c t o r s . The program r e c t i f i e s th e problem by in c r e a s in g t h e s i z e o f u t i l i t y t r a c t o r ( s ) i n in cre m e n ts o f 0 .7 5 PTO kW (1 HP), and r e c a l c u l a t i n g t h e p ro ­ d u c t i v i t y o f each o p e r a tio n , and p re p a r in g th e o p e ra tio n s sc h e d u le from th e b e g in n in g a g a in . I f s e l e c te d number o f u t i l i t y t r a c t o r s o f maximum p e rm itte d s i z e can n o t f i n i s h t h e w ork, th e program t r a n s f e r s u n f in is h e d work from u t i l i t y t r a c t o r ( s ) t o tilla g e tra c to r(s ). 3. T il l a g e t r a c t o r ( s ) i s fo rc e d t o rem ain i d l e : T il l a g e t r a c t o r ( s ) may b e fo rc e d t o rem ain i d l e f o r p a r t o f t h e tim e i f h a r v e s tin g o p e r a tio n s cannot b e accom plished a t a r a t e t h a t e n a b le s t i l l a g e t r a c t o r ( s ) t o work f u l l tim e . T h is may r e s u l t 57 in v i o l a t i o n o f a c o m p letio n d a te c o n s t r a i n t f o r a t i l l a g e o p e ra tio n . l b r e c t i f y t h e problem , t h e program in c r e a s e s th e s i z e ( i n in c re m e n ts o f 0 .7 5 PTO kW (1 HP)) o r n u n b er o f t i l l a g e t r a c t o r ( s ) and r e c a l c u l a t e s t h e p r o d u c t i v it y o f each o p e r a tio n and s t a r t s p r e p a r a tio n o f o p e r a tio n s sc h e d u le from t h e b e g in n in g . 3 .9 Labor The l a b o r r e q u i r e d f o r o p e r a tin g m achines and t h e d i s t r i b u t i o n o f l a b o r d u r in g t h e y e a r a r e i n p o r t a n t c o n s id e r a tio n s f o r farm management. The w eekly o p e r a tio n s s c h e d u le ( f o r 50 p e r c e n t p r o b a b i l i t y ) was u sed t o c a l c u l a t e l a b o r re q u ire m e n ts . F i e ld l a b o r h o u rs r e q u ir e d d u rin g each week w ere c a l c u l a t e d by sum ning f i e l d work h o u rs u se d f o r d i f f e r e n t o p e r a tio n s d u r in g t h e week. T o ta l r e q u ir e d f i e l d w orking h o u rs d u rin g eac h work week o f t h e y e a r f o r t h e e x a n p le farm a r e p l o t t e d i n F ig u re 3 .7 , The n u n b er o f men r e q u ir e d p e r week w ere computed from th e fo llo w in g re la tio n s h ip : n NCP NMEN, = Z Z 1 i= l k=l WHDUR., m ire H ^ ik (4 ) w here NMENi = n u n b e r o f men r e q u i r e d d u rin g week i WHOURi^r = f i e l d work h o u rs d u rin g week i f o r w hich o p e r a tio n k was p e rfo rm e d by pow er u n i t r ( t r a c t o r o r SP com bine) HDUH^ = f i e l d work h o u rs a v a i l a b l e d u rin g week i f o r th e k th o p e ra tio n n = n u n b er o f f i e l d o p e r a tio n s 58 NOP = number o f f i e l d o p e ra tio n s The number o f men re q u ire d d u ring each work week o f th e y e a r f o r th e example farm i s shown in F ig u re 3 .7 . A f r a c tio n a l man can be i n t e r ­ p re te d a s meaning t h a t th e man i s re q u ire d f o r only a p a r t o f th e week. The r a t i o o f f i e l d tim e t o th e t o t a l tim e la b o r i s p a id i s d e fin e d a s sc h e d u lin g e ffic ie n c y 7. The t o t a l la b o r hours re q u ire d f o r o p e ra tin g f i e l d m achinery d u rin g th e y e ar were computed by d iv id in g t o t a l f i e l d work ho u rs by sc h e d u lin g e ff ic ie n c y (0 .8 5 ) and th en m u ltip ly in g by a f a c t o r o f 1 .3 . T h irty p e rc e n t e x tr a la b o r was added to account f o r la b o r tim e sp e n t in r e p a i r s , o ff-s e a s o n m achinery m aintenance and to o lin g up. T o ta l annual la b o r re q u ire d f o r th e example farm i s shewn in T able 3 .8 . 3.10 Fuel D ie se l f u e l was assumed to be used in a l l power u n i ts . t i o n f o r each f i e l d o p e ra tio n was c a c u la te d s e p a ra te ly . Fuel consump­ The f u e l e f f ic ie n c y , FUELEFF ( litr e s /k W h ) , was computed a s a fu n c tio n o f lo ad on th e power u n it f o r t r a c t o r powered o p e ra tio n s (e q u a tio n 5; Hunt, 1966). The d a ta used f o r dev eloping t h i s e q u atio n i s re p o rte d in T able 2 .2 , Hunt, 1977. FUELEFF = 2.64 PR + 3.90 - 0 .2 0 (738 PR + 173)1/ 2 (5 ) where PR = th e r a t i o o f e q u iv a le n t PTO power re q u ire d t o t h a t maximum a v a ila b le frcm th e PTO. Fuel consumption f o r combining corn was assumed t o be 14.97 l i t r e s / h e c ta re (1 .6 g a llo n s /a c r e ; Ayres, 1976), f o r combining soybeans 10.29 l i t r e s / h e c t a r e (1 .1 g a llo n s /a c re ; A yres, 1976) and f o r o th e r conbining (field (man-weeks) Labor R equired work h o u rs) 140-i ::::::::: ::::::::: A p ril May June J u ly August September O ctober November Beginning Date o f th e Week F ig u re 3 .7 . Labor D is trib u tio n a t th e Example Farm f o r an Average Year. 60 o p e ra tio n s 13.56 l i t r e s / h e c t a r e (1 .4 5 g a llo n s /a c r e ; Bowers, 1 9 7 0 ), i r r e s p e c t i v e o f th e s i z e o f combine o r c o n d itio n o f c ro p . Fuel consuription f o r each f i e l d o p e ra tio n o f t h e exam ple farm i s shown in T ab le 3 .6 and th e t o t a l annual f u e l consum ption i s shown in T able 3 .8 . 3.11 Cost A n a ly sis C ost c a lc u la tio n s w ere made, a s d e s c rib e d below , t o e s tim a te th e av erag e an n u al c o s t o f th e m achinery sy ste m s e l e c te d . 3 .1 1 .1 L i s t p r i c e s o f m achines The l i s t p r i c e s o f t r a c t o r s , c a r b in e s , and r o t a r y c u t t e r s w ere ta k e n from t h e O f f i c i a l G uide t o T r a c to r s and Farm Equipm ent ( F a l l 1976). A r e g r e s s io n r e l a t i o n s h i p was developed f o r r e l a t i n g tw o-w heel d r iv e d i e s e l t r a c t o r l i s t p r i c e t o t r a c t o r s i z e in PTD pow er. o f a l l makes w ere c o n s id e re d . C u rre n t m odels T r a c to r s i z e ra n g e c o n s id e re d was from 2 2 .4 t o 111.9 PIO kW (30 to 150 HP). T h is ra n g e was d iv id e d i n t o 12 g ro u p s, e ac h group r e p r e s e n tin g a ra n g e o f 7 .5 PTO kW (10 HP). Four t r a c t o r s o f d i f f e r e n t makes w ere s e l e c te d from each power group in o r d e r t o g iv e e q u a l w eig h t t o a l l t r a c t o r s i z e s . P r i c e , s i z e , and make o f each s e l e c te d t r a c t o r a r e g iv e n in T able A.4B. r e l a t i o n s h i p s w ere d e v elo p ed . S e v e ra l r e g r e s s io n The c o e f f i c i e n t o f d e te rm in a tio n (R2 ) was h ig h e s t (0 .9 9 ) f o r t h e fo llo w in g r e l a t i o n , w hich was a d o p te d : L i s t P r i c e = 233.26 (PTO kW) - 0 .3 0 8 (PTO kW)2 (8 .3 3 ) (0 .0 7 2 ) (6 ) 61 T ab le 3 .6 F u e l R equirem ents f o r F i e ld O p e ra tio n s o f t h e Example Farm. O p e ratio n T ra c to r c a te g o ry u sed Load fa c to r (PR) HJKTFFF (litr e s /kWh) Fuel consump­ t io n (litre s / ha) T o ta l fu e l consurqpt io n (litre s ) Cbm a f t e r w heat H arvest S pread f e r t i l i z e r M oldboard plow D isc harrow P la n t Apply ammonia Row c u l t i v a t e U tility T illa g e T illa g e U tility U tility U tility .31 .80 .80 .80 .80 .80 39.8 6 4 .7 6 4 .7 6 4 .7 6 4 .7 6 4 .7 15.0 1 .1 18.0 7 .9 4 .3 4 .7 4 .2 1668.6 121.9 2001.8 875.8 4 8 1 .7 5 25.5 4 6 9 .2 Corn a f t e r c o rn H a rv est D isc S pread f e r t i l i z e r M oldboard plow D isc harrow P la n t Apply anmonia Row c u l t i v a t e T illa g e U tility T illa g e T illa g e U tility U tility U tility .80 .31 .80 .80 .80 .80 .80 6 4 .7 3 9 .8 6 4 .7 6 4 .7 6 4 .7 6 4 .7 6 4 .7 1 5 .0 5 .6 1 .1 1 8 .0 7 .9 4 .3 4 .7 4 .2 1668.6 6 2 5 .5 121.9 2 001.8 875.8 4 8 1 .7 525.5 4 6 9 .2 1147.2 6 2 5 .5 2001.8 875.8 4 8 1 .7 181.5 4 6 9 .2 1512.2 2001.8 1000.9 4 5 2 .8 121.9 1 8 1 .5 Soybeans H arv est D isc M oldboard plow D isc harrow P la n t Spray h e r b ic id e s Row c u l t i v a t e T il l a g e T il l a g e T illa g e U tility U tility U tility .80 .80 .80 .80 .25 .80 6 4 .7 6 4 .7 6 4 .7 6 4 .7 3 5.6 6 4 .7 1 0 .3 5 .6 1 8 .0 7 .9 4 .3 1 .6 4 .2 Wheat H arv est M oldboard plow D isc h a rro w -d rag Seed d r i l l T o p d ress n itr o g e n Spray h e r b ic id e T illa g e T illa g e U tility U tility U tility .80 .80 .48 .31 .25 6 4 .7 6 4 .7 5 8 .3 3 9 .8 3 5 .6 1 3 .6 18.0 9 .0 4 .0 1 .1 1 .6 62 U t i l i t y and a l f a l f a t r a c t o r s were assu red t o be 4 y e a rs o ld when a cq u ired f o r u se . The purchase p r ic e o f th e s e u n its was assumed t o be 48 p e rc e n t o f th e l i s t p r ic e o f a new t r a c t o r o f th e same s iz e (Runt, 1977). L is t p r ic e s used in th e model f o r c a rb in e s were th e averages o f p r i c e s o f d i f f e r e n t makes o f c a rb in e s o f th e same s i z e . The makes and th e models t h a t were used t o compute average p r ic e s o f d i f f e r e n t s iz e s o f c a rb in e s and t h e i r p r ic e s a re shown in T able A.4C along w ith th e av erag e p r ic e o f each s i z e . The p r ic e s o f c o m head s, g ra in heads, and p ic k up heads were a ls o s im ila r ly determ ined and a r e shown in T ab les A.4D, A.4E and A.4F, r e s p e c tiv e ly . L is t p r ic e s o f a l l o th e r implements were tak en from th e A g ric u ltu ra l Whole Goods P r ic e L is t o f a m achinery m an u factu rer. In g e n e ra l, th e models used were "middle o f th e range" models, i . e . th e y were n e ith e r th e low est nor h ig h e s t p r ic e d m odels. The p r ic e o f each sta n d a rd u n i t, and wherever re q u ire d , th e p r ic e o f implement w heels and t i r e s , c h is e l s , sweeps, and plow bottom s were in clu d ed . A ttachm ents o r e x tr a o p tio n s w ere n o t c o n sid e re d f o r any equipm ent. T able A.4A shows th e p r i c e s a ssu re d in t h i s stu d y f o r a l l t r a c t o r powered f i e l d m achines. 3 .1 1 .2 Machinery c o s ts Machinery c o s ts in c lu d e d e p re c ia tio n , r e p a i r and m aintenance, i n t e r e s t , housing, in su ra n c e and ta x . D e p re c ia tio n was c a lc u la te d by th e s t r a i g h t l i n e method, assum ing a te n p e rc e n t sa lv a g e v a lu e . u s e f u l l i f e o f a machine was c a lc u la te d by d iv id in g th e e stim a te d The 63 w earout l i f e o f th e machine (Bowers, 1970; A g ric u ltu ra l E ngineers Yearbook, 1977) by th e annual u se o f th e machine. Maximum u s e fu l l i f e o f each machine was assumed equal to 8 years in t h i s study. R epair c o s ts o v er th e w ear-out l i f e o f a machine were taken a s a fix e d p erc en ta g e o f th e purchase p r i c e o f th a t machine and were p ro ­ r a te d a cco rd in g t o annual machine u se . The assumed v a lu e s f o r t o t a l r e p a i r c o s ts in w ear-out l i f e , a s a p e rc e n t o f i n i t i a l purchase p r i c e , were tak e n from th e A g ric u ltu ra l E ngineers Yearbook (1977). Some re c e n t s tu d ie s (Hunt, 1974) have in d ic a te d th a t a c tu a l r e p a i r c o s ts a re s i g n i ­ f i c a n t l y l e s s th an th e s e v a lu e s. But sin c e r e l i a b l e info rm atio n on t o t a l r e p a i r c o s ts o f a l l m achines was not a v a ila b le from any o th e r so u rc e , A g ric u ltu ra l E ngineers Yearbook (1977) v alu e s were used. The e f f e c t o f reduced r e p a ir c o s ts would not be s i g n i f ic a n t on t o t a l m achinery c o s ts (S e c tio n 5 .6 .4 ) . Annual c o s ts f o r i n t e r e s t , housing, and in su ra n ce were c a lc u la te d a s fix e d p e rc e n ta g e s o f th e l i s t p r ic e o f th e m achine. Since th e r e i s no ta x on f i e l d m achinery in M ichigan, ta x was n o t in clu d ed in th e m achinery c o s ts . Assumed m achinery c o s t f a c to r s a re given in T able A. 5. Machinery c o s ts f o r th e ex anple farm a r e shown in T able 3 .7 . Annual la b o r c o s t was c a lc u la te d by m u ltip ly in g annual la b o r h o u rs by th e h o u rly wage r a t e . Assumed v a lu e s o f la b o r r a t e , d ie s e l p r i c e , and eng ine o i l and f i l t e r expenses a re given in Table A .5. T able 3 .8 shows a l l c a te g o r ie s o f annual m achinery r e l a te d c o s ts f o r th e example farm . 64 T able 3 .7 M achinery C o sts f o r th e Example Farm. Machine Two t i l l a g e t r a c t o r s U tility tra c to r SP ccmbine Com head G rain head Two moldboard plows D isc harrow G rain d r i l l P la n te r Anroonia a p p lic a to r Row c u l t i v a t o r Spin sp re a d e r S p rayer Sum C o s t/h e c ta re T hble 3 .8 In s . + Housing ( $ /y r ) R ep air ( $ /y r ) T o ta l ( $ /y r ) 1837 231 1639 582 171 296 271 185 438 163 144 87 80 371 47 331 118 35 60 55 37 88 33 29 18 16 1016 462 2612 810 60 623 655 175 1243 312 180 85 85 7400 1263 8499 2831 654 1651 1595 819 2764 879 681 386 364 6123 13.73 1237 2 .7 7 8317 18.65 29785 66.78 D eprecia­ t io n ( $ /y r ) In t­ e re st 37115 4657 33103 11753 3452 5973 5469 3746 8840 3300 2913 1749 1620 4176 524 3917 1322 388 672 615 421 994 371 328 197 182 123690 277.33 14108 31.63 P r ic e ($) ($/yr) Average Annual M achinery R e la te d C o sts f o r th e Example Farm. T o ta l Investm ent in m achinery $ /y e a r $123690 M achinery c o s ts $ /h e c ta r e 277.33 29,785 66.78 Labor c o s ts 1998 ho u rs 6 ,495 14.55 F uel and o i l c o s ts 23968 l i t r e s o f d ie s e l fu el 2,803 6 .2 8 39,083 87.63 T o ta l m achinery r e l a t e d c o s ts 4. IMPLEMENTATION GF THE MCDEL A nalyses w ere made f o r te n c ro p r o t a t i o n s (T ab le 4 .1 ) , in v o lv in g c o rn , so y b ean s, f i e l d b e a n s, w heat and a l f a l f a . The r o t a t i o n s ran g e from a s i n g l e c ro p t o r o t a t i o n s in v o lv in g s e v e r a l c ro p s . Some o f th e s e c ro p r o t a t i o n s a r e common in so u th e rn M ichigan w h ile i n t e r e s t i s in c r e a s in g in o t h e r s . T hree t i l l a g e system s ( n o - t i l l , c h i s e l plow, and m oldboard plow) w ere s e l e c te d f o r t h i s s tu d y . They r e p r e s e n t " p o in ts " on t h e spectrum o f te c h n o lo g ie s p r e s e n tly u se d in s o u th e rn M ichigan. system s a r e n o t u se d f o r a l l c ro p s . A ll t h r e e t i l l a g e The n o - t i l l system i s n o rm ally u sed o n ly f o r c o rn , th e c h i s e l plow system f o r c o rn , soybeans and w h e a t, and t h e m oldboard plow system i s u se d f o r a l l c ro p s . T hree l e v e l s o f t i l l a g e i n t e n s i t y w ere c o n sid e re d f o r each c ro p ro ta tio n . The t i l l a g e s y s ta n u se d f o r each c ro p a t each l e v e l o f t i l l a g e i n t e n s i t y f a r each r o t a t i o n i s shown in T able 4 .1 . S in c e soybeans a r e n o t n o rm ally r a i s e d u s in g t h e n o - t i l l sy stem in M ichigan, t h e r e a r e 29 c ro p p ro d u c tio n system s t h a t w ere s e l e c te d f o r a n a l y s i s . T able A .l shows f i e l d o p e r a tio n s t h a t w ere a s s u re d f o r each c ro p u nder each t i l l a g e system , a lo n g w ith th e s e l e c te d c a le n d a r d a te c o n s t r a i n t s f o r each (R o b e rtso n , 1977; L ucas, 1976). The c a le n d a r d a te c o n s t r a i n t s w ere s e l e c te d in such a manner t h a t i f th e o p e ra tio n was co u p le te d w ith in th e s e l e c te d p e rio d w ith t h e s p e c i f i e d d e sig n p r o b a b i l i t y (80 p e r c e n t) , o p e ra tio n tim e lin e s s w ould be a c c e p ta b le . 65 T able 4 .1 D e sc rip tio n o f th e S e le c te d Cropping Systems. Crop ro ta tio n * H ighest le v e l o f t i l l a g e in te n s i t y (HLTI) Middle le v e l o f t i l l a g e in te n s i t y (MLTI) Lowest le v e l o f t i l l a g e in te n s ity (LLTI) c c C C C MB** CH+ S MB C CH s s c s MB C FB CC S W C C IB W C MB C MB C MB C WA A C S WA A C C S WA A C C FB W A A S S C S C S MB IB MB CH CH FB NT C CH IB W CH MB C C NT NT C C NT NT C W C S W C MB C S MB MB IB MB MB MB CH W MB A C C MB CH C MB CH W A MB MB MB C S W MB MB MB C C S MB MB M3 IB C C MB MB MB C C A A MB W A A MB MB W A A MB MB C W MB CH C S MB CH C C MB CH C C MB CH CH FB MB NT W CH A A MB W A A CH MB S W A A CH CH MB A IB W A MB CH MB *C - co rn , S - soybeans, ID - f i e l d beans, W - wheat, A - a l f a l f a . **MB - Moldboard plow t i l l a g e system . +CH - C h ise l plow t i l l a g e sy s ta n . ++NT - N o - t i l l t i l l a g e system . S W CH CH FB MB A NT CH MB W C S W CH A A A NT CH CH MB C C S W A 1 NT NT CH CH MB C C IB W A I NT NT MB CH MB 67 Except f o r th e f i e l d work d a ta shown in Table A . l , a l l o th e r a sp e c ts o f th e technology used fo r th e crop prod u ctio n system s were fix e d . The same s o i l , c lim a te , machine c h a r a c t e r i s t i c s and management p o lic ie s were a p p lie d t o a l l system s, and th u s were assumed to have no in flu e n c e on th e ccm parisons t o b e made among system s. Appendix A shows th e c c r p l e t e s e t o f in p u t d a ta used. 4 .1 Comparisons The 29 crop p ro d u ctio n system s (T able 4 . 1 ) were analyzed u sin g th e d a ta in Appendix A and th e computer program, d isc u sse d in C hapter 3, t o d eteim in e th e e f f e c t o f : 1. t i l l a g e in te n s i t y , and 2. crop r o ta tio n on: a. c o s t and s iz e o f f i e l d m achinery, b. t o t a l la b o r f o r f i e l d work and d i s t r ib u t i o n o f la b o r d urin g th e y e a r, and c. f u e l req u irem en ts f o r f i e l d work A s e n s i t i v i t y a n a ly s is was made t o measure th e e f f e c t o f th e fo llo w in g d e sig n param eters on m achinery req u irem en ts and c o s ts : 1. Design p r o b a b ility le v e l, 2. F ie ld w orking hours p e r day, 3. Number o f t i l l a g e t r a c t o r s id le d f o r each h a rv e s te r o p e ra tin g in th e f i e l d , and 4. Machinery c o s t f a c to r s The C C S W crop r o t a t io n and th e HLTI were s e le c te d to i l l u s t r a t e th e e f f e c t o f above design p aram eters. 68 4 .2 T im eliness C osts For a given crop r o ta tio n and t i l l a g e system , th e c o s ts r e la te d to th e s e t o f m achinery used a re th e c o s ts f o r m achinery ( in c lu d in g fu e l and o i l ) , la b o r, and tim e lin e s s . The computer model d e sc rib e d in C hapter 3 was used t o c a lc u la te m achinery and la b o r c o s ts . c o s ts were n o t co n sid ered e x p l i c i t l y . T im eliness R ath er, c a le n d a r d a te c o n s tr a in ts f o r th e f i e l d o p e ra tio n s o f each crop were h e ld c o n sta n t a s f a r a s f e a s ib le in o rd e r t o keep th e tim e lin e s s o f o p e ra tio n s c o n sta n t a c ro ss a l l cropping s y s ta n s . N e v e rth e le ss, tim e lin e s s o f o p e ra tio n s , a s determ ined by median co u p let ion d a te , d id vary from one cropping system t o a n o th e r. The tim e lin e s s o f o p e ra tio n s v a r ie s w ith th e s iz e o f machinery which i s la r g e ly determ ined by th e power req u irem en ts d uring th e peak work seaso n . A change in crop p ro d u ctio n system may change th e le n g th o r c a le n d a r p e rio d o f th e peak work season, and consequently power req u irem en ts and tim e lin e s s o f o p e ra tio n s . The tim e lin e s s o f o p e ra tio n s , f o r a given crop r o t a t io n and t i l l a g e system , a ls o v a rie d w ith th e farm s i z e . However, th e tim e lin e s s o f p la n tin g o p e ra tio n s d id n o t vary a s much a s t h a t o f h a rv e s tin g o p e ra tio n s . T his was so because t r a c t o r s were assumed t o be a v a ila b le a t 0.75 kW (1 PTCHP) s i z e increm ents; w hereas SP combines were assumed t o be a v a i l ­ a b le o nly a t 2-row s i z e in crem ents. The combine s iz e was determ ined by th e h a rv e s tin g p e rio d o f th e crop f o r which th e r a t i o o f th e a v a ila b le f i e l d tim e ( a t th e s e le c te d design p r o b a b ility l e v e l) to th e re q u ire d f i e l d tim e (cro p a re a / p r o d u c tiv ity o f th e given combine s iz e f o r th e c ro p ) f o r th e h a rv e stin g 69 o p e ra tio n was s m a lle s t o f a l l th e crops inv o lv ed in th e cro p r o t a t i o n . H e re a fte r t h i s s m a lle s t r a t i o i s c a lle d R. For a given c a rb in e s i z e , a s th e farm s i z e was in c re a s e d , th e v a lu e o f R d e crea se d , and co n seq u e n tly tim e lin e s s c o s t o f th e h a rv e s tin g o p e ra tio n in c re a s e d . At a c e r t a i n farm s i z e , th e v a lu e o f R became one; and a f u r t h e r in c re a s e in t h e farm s i z e n e c e s s ita te d s e le c tio n o f a l a r g e r c a p a c ity combine. S e le c tio n o f a l a r g e r c a p a c ity combine, a t t h a t farm s i z e , caused a c o n s id e ra b le in c re a s e in th e v a lu e o f R; and c o n seq u en tly d e c re a se d tim e lin e s s c o s t . Thus, t o keep tim e lin e s s c o s ts o f h a rv e s tin g o p e ra tio n s a s n e a rly eq u al a s f e a s i b l e , i t was e s s e n t i a l t o keep th e v a lu e o f R c o n s ta n t f o r a l l system s t o be compared. T h e re fo re , to coup a r e cro p r o t a t io n s , combine s i z e was fix e d ( a t 2, 4 , 6, o r 8-row ) and farm s i z e was v a rie d so t h a t th e v a lu e o f R was n e a rly e q u al t o one. F o r a giv en c ro p r o t a t io n and combine s i z e , th e maximum fan n s i z e t h a t makes R eq u al t o one i s h e r e a f t e r r e f e r r e d a s th e maximum a re a t h a t th e g iv en c a rb in e s i z e can h a rv e s t in one seaso n . F o r r o t a t i o n s in v o lv in g a l f a l f a , th e maximum farm s i z e s t h a t 6 and 8-row c a rb in e s can h a rv e s t in one season w ere b ig g e r th a n 475 h e c ta r e s . Such b ig cash cro p farm s a r e r a r e in M ichigan. T h e re fo re , a n a ly s is o f th e s e r o t a t i o n s was r e s t r i c t e d o n ly t o maximum farm s i z e s t h a t 2 and 4-row combines can h a rv e s t in one seaso n . 5. RESULTS F ie ld m achinery re q u ire m e n ts f o r t h e s e l e c te d c ro p p ro d u c tio n system s (T a b le 4 .1 ) w ere c a lc u la te d u s in g t h e com puter model d e s c rib e d in C h ap ter 3 and in p u t d a ta o f Appendix A. R eq u ired f i e l d m achinery s y s ta n s f o r t h e s e l e c te d M ichigan c ro p p ro d u c tio n system s a r e g iv en in Appendix C, T able C .l . Cbst c a l c u l a t i o n s w ere made u s in g t h e c o s t f a c t o r s g iv en in T ab le A .5 t o d e te rm in e a v e ra g e annual m achinery r e l a t e d c o s ts f o r th e s e sy ste m s. M achinery r e l a t e d c o s ts a r e shown in S e c tio n 5 .1 below . 5 .1 E ffe c t o f T illa g e In te n s ity The e f f e c t o f t i l l a g e i n t e n s i t y on s i z e , u s e , and c o s t s o f f i e l d m achinery was d eterm in ed by v a ry in g t h e l e v e l o f t i l l a g e i n t e n s i t y f o r t h e te n c ro p r o t a t i o n s shown in T a b le 4 .1 , k e ep in g a l l o t h e r p a ra m e te rs fix e d ; and c o n p a rin g t h e f i e l d m achinery re q u ire m e n ts . d e sig n p r o b a b i l it y was f ix e d a t t h e 80 p e r c e n t l e v e l . The S u ffic ie n t a d d itio n a l la b o r and m achinery was assum ed t o b e a v a i la b l e t o t r a n s p o r t th e h a rv e s te d c ro p s t o t h e fa rm s te a d . T h e re fo re , no t i l l a g e t r a c t o r was k e p t i d l e when a h a r v e s t e r was o p e r a tin g i n th e f i e l d . O th e r d a ta were t h e same a s g iv en in Appendix A. T hree l e v e l s o f t i l l a g e i n t e n s i t y , d e s c rib e d in C h a p te r 4 , w ere c o n sid e re d . The t i l l a g e sy stem u se d f o r eac h c ro p a t each t i l l a g e 70 71 i n t e n s i t y l e v e l i s g iv e n in T ab le 4 .1 . The m achinery re q u ire m e n ts and c o s t s f o r eac h c ro p r o t a t i o n a r e shewn in T a b le s 5 .1 th ro u g h 5 .1 0 . In g e n e r a l, r e d u c tio n i n t h e t i l l a g e i n t e n s i t y re d u c e d th e s i z e o f t r a c t o r s and t r a c t o r pow ered im plem ents and th e re b y t h e annual c o s t o f t h e f i e l d m ach in ery . M achinery u t i l i z a t i o n in c r e a s e d w ith th e u se o f t h e c h i s e l plow t i l l a g e sy stem (CUTS) o v e r t h a t o f t h e m oldboard plow t i l l a g e sy stem (MBTS) b e c a u se f a l l c h i s e l plow ing was p e rm itte d w h ile f a l l m oldboard plo w in g was n o t (b e c a u se o f an e ro s io n r i s k ) . M achinery u t i l i z a t i o n was a ls o h ig h e r f o r t h e n o - t i l l t i l l a g e sy stem (WITS) com pared t o t h e MBTS. The amount o f r e d u c tio n i n t h e t o t a l f i e l d m achinery r e l a t e d c o s t s on a p e r u n i t a r e a b a s i s (TMRC) v a r i e d f o r d i f f e r e n t c ro p r o t a ­ tio n s . R ed u ctio n in t h e TMRC was l a r g e r f o r th o s e r o t a t i o n s i n w hich t h e t i l l a g e i n t e n s i t y was re d u c e d f o r a l l c ro p s . Thus, f o r t h e c o n tin u o u s c o rn r o t a t i o n , t h e u s e o f t h e CHTS re d u c e d t h e TMRC by a s much a s 20 p e r c e n t and u s e o f t h e NITS re d u c e d t h e TMRC by a s much a s 25 p e r c e n t com pared t o t h e MBTS. However, t h e r e d u c tio n i n t h e TMRC was much l e s s f o r th o s e c ro p r o t a t i o n s in w hich d i f f e r e n t c ro p s a r e grown u s in g d i f f e r e n t t i l l a g e sy ste m s a t t h e m id d le and t h e lo w e st l e v e l o f t i l l a g e in te n s ity . I b r some c ro p r o t a t i o n s a t t h e m id d le l e v e l o f t i l l a g e i n t e n s i t y (MLTI) c h i s e l plow and s t a l k s h re d d e r im plem ents w ere r e q u ir e d in a d d it i o n t o t h e im plem ents r e q u ir e d f o r t h e same c ro p r o t a t i o n a t t h e h i g h e s t l e v e l o f t i l l a g e i n t e n s i t y (HLTI). Some c ro p r o t a t i o n s a t t h e lo w e s t l e v e l o f t i l l a g e i n t e n s i t y (LLTI) r e q u i r e th e u s e o f a l l t h r e e d i f f e r e n t t i l l a g e sy ste m s f o r d i f f e r e n t c ro p s . F o r th e s e r o t a t i o n s , n o - t i l l p l a n t e r , c h i s e l plow , and s t a l k sh re d d e r im plem ents w ere r e q u ir e d 72 a t th e LLTI in a d d itio n t o th e implements (ex cep t row c u lt i v a t o r ) re q u ire d a t th e HLTI. T h is i s th e reason th a t th e TMRC d ecreased so l i t t l e w ith th e d ecrease in t i l l a g e i n te n s i t y f o r crop r o ta tio n s in v o lv in g th e crops o f a l f a l f a and f i e l d bean s. 5 .1 .1 Continuous corn (C C) crop r o ta tio n Table 5.1 shows t h e e f f e c t o f t i l l a g e i n te n s i t y on s i z e , u se , and c o s ts o f f i e l d m achinery f o r th e C C r o t a t i o n . The u se o f th e CUTS reduced t i l l a g e t r a c t o r power req u irem en ts by 61 p e rc e n t and th ereb y TMRC by about 20 p e rc e n t compared t o t h a t o f th e MBTS. T illa g e t r a c t o r power req u irem en ts w ere l e s s f o r th e CUTS because c h is e l plowing r e q u ire s l e s s energy th an m oldboard plow ing and f a l l c h is e l plow ing was p e rm itte d w hereas f a l l moldboard plow ing was n o t. No t i l l a g e o p e ra tio n i s perform ed u nder t h e NTTS, and th e t i l l a g e t r a c t o r was used f o r n o - t i l l p la n tin g and aranonia a p p lic a tio n o p e ra tio n s o n ly . T h erefo re, th e u se o f th e NTTS caused a 67 p e rc e n t re d u c tio n in t i l l a g e t r a c t o r power req u irem en ts and th e re b y a 25 p e rc e n t re d u c tio n in th e TMRC conpared t o th e MBTS. The re d u c tio n in th e t i l l a g e t r a c t o r power req u irem en ts and th e TMRC was n o t a s much as s t a t e d above f o r th e 79.3 and 136 h e c ta r e farm s i z e s . Bor th e 79.3 h e c ta re farm s i z e , th e sm a lle s t p e rm itte d t i l l a g e and u t i l i t y t r a c t o r s were s e le c te d and th ey could not be used t o t h e i r f u l l c a p a c ity . F or th e 136 h e c ta re farm s i z e , a 4-row n o - t i l l p l a n t e r was n o t s u f f i c i e n t and th e r e f o r e an 8-row n o - t i l l p la n te r had to b e s e le c te d which re q u ire d a 4 4 .7 PlOkW t r a c t o r . t r a c t o r co u ld n o t be u t i l i z e d t o c a p a c ity . T his Table 5.1A T illa g e i n te n s i t y le v e l E ffe c t o f T illa g e In te n sity on S iz e , Use and C osts o f F ie ld Machinery fo r C C R otation. M achinery S iz e and Use T illa g e t r a c t o r s U tility tra c to rs No. & s i z e Use No. & s i z e Use (FTOkW) (h r) (PTOkW) (h r ) In itia l investm ent in m achinery Labor c o s ts Fuel and o il c o s ts T o ta l m achinery r e l a te d c o s ts -------------- ( $ /h a ) ---------------- ----------------------Farm S iz e = 7 9 .3 H ectares Confcine S iz e = 2-Row H ighest Middle Lowest 1-5 5 .9 1-29.8 1-29.8 170 194 128 1-22.4 1 -22.4 1-22.4 231 235 119 581.96 496.21 516.72 1 -9 6 .2 1 -3 7 .3 1 -4 4 .7 170 266 146 1 -3 2 .8 1-29.1 1 -2 2 .4 277 314 204 507.72 374.46 424.08 2-6 4 .1 1-4 9 .2 1 -4 3 .3 170 269 202 1-43.3 1-38.8 1-22.4 286 321 272 484.32 360.97 351.33 2-8 1 .3 1-62.6 1-54.4 170 268 203 1-55.2 1 -4 8 .5 1 -2 2 .4 21.52 26.39 17.99 7.07 5 .6 6 3.71 138.35 116.49 115.00 21.03 20.06 16.88 7.09 5.6 6 3.71 133.56 107.42 100.23 Farm S iz e = 230.3 H ectares Cbntoine S ize = 8-Row H ighest Middle Lowest 166.28 149.42 138.08 Farm S iz e = 181.3 H ectares Cbrrbine S iz e = 6--Row H ighest Middle Lowest 7.04 5 .6 3 3.71 Farm S iz e = 136.0 H ectares Oonbine S iz e = 4--Row H ighest Middle Lowest 34.03 35.78 24.36 291 332 345 475.63 357.54 337.35 16.70 16.04 14.90 7.09 5 .0 8 3.71 127.61 103.14 95.73 Thble 5 . IB Median Conpletion Dates for P lanting and Harvesting in C C R otation. T illa g e in te n s ity le v e l T o ta l machinery r e l a t e d c o s ts ($ /h a ) P la n tin g o p e ra tio n s H arv estin g o p e ra tio n s Com Com -(days a f t e r s t a r t i n g d a te c o n s t r a i n t) ----- Farm S iz e = 7 9 .3 H ectares Cbrrbine S ize = 2-Row H ighest Middle Lowest 166.28 149.42 138.08 11.1 10.5 9 .2 Farm S ize = 136.0 H ectares Combine S iz e = 4-Row H ighest Middle Lowest 138.35 116.49 115.00 11.9 12.9 10.2 133.56 107.42 100.23 12.0 13.0 13.0 Lowest 127.61 103.14 95.73 14.0 14.0 14.0 Farm S ize = 230.3 H ectares Cbnbine S iz e = 8-Row H ighest Middle 14.0 14.0 14.0 Farm S ize = 181.3 H ectares Combine S iz e = 6-Row H ighest Middle lo w est 14.0 14.0 14.0 12.0 13.0 13.0 14.0 14.0 14.0 75 5 .1 .2 C ontinuous soybean (S S) crop r o ta tio n The CHTS reduced t i l l a g e t r a c t o r power req u irem en ts by about 40 p e rc e n t and t h e TMRC by about 10 p e rc e n t compared t o th e MBTS, a s shown in T able 5 .2 . Soybeans a re not norm ally grown by n o - t i l l p la n tin g w ith o u t prim ary t i l l a g e in M ichigan. 5 .1 .3 C om -soybean (C S) cro p r o ta tio n The MBTS was used f o r b o th corn and soybeans a t th e HLTI and th e CUTS was used a t th e MLTI. But a t th e LLTI, corn was r a i s e d u sin g th e NITS and th e CHTS was used f o r soybeans. W ith t h e d e c re a se in t i l l a g e i n t e n s i t y , maximum re d u c tio n in th e t i l l a g e t r a c t o r power req u ire m e n ts and th e TMRC o c c u rre d f o r th e 214.1 h e c ta r e farm s i z e , a s shown in T able 5 .3 . The t i l l a g e t r a c t o r power req u ire m e n ts were 64 p e rc e n t l e s s and th e TMRC w ere about 14 p e rc e n t l e s s f o r b o th th e MLTI and th e LLTI compared t o th e HLTI and t i l l a g e t r a c t o r use was h ig h e r a t b o th t h e MLTI and th e LLTI conpared t o th e HLTI. There was no s iz a b le d if f e r e n c e in median c o u p le t io n d a te s o f p la n tin g and h a rv e s tin g o p e ra tio n s among th e th r e e l e v e ls o f t i l l a g e i n t e n s i t y , a s shown in T able 5.3B . The re d u c tio n in th e t i l l a g e t r a c t o r power re q u ire m e n ts o r th e TMRC was n o t a s much f o r o th e r farm s iz e s e i t h e r b ecau se t h e farm s i z e was s o sm all t h a t even th e s m a lle s t p e rm itte d t r a c t o r s i z e c o u ld n o t b e f u l l y u t i l i z e d , o r b e ca u se a l a r g e r t r a c t o r had t o b e s e le c te d t o p u l l th e p l a n t e r t h a t was m atched w ith t h e conbine s i z e . o f t h e MLTI. The LLTI d id n o t reduce TMRC any more th a n t h a t One reaso n was t h a t f o r th e LLTI two p l a n t e r s w ere Table 5.2A T illa g e i n te n s i t y le v e l E ffe c t o f T illa g e In te n sity on S iz e , Use and Costs o f F ie ld Machinery for Machinery S ize and Use T illa g e t r a c t o r s U tility tra c to rs No. & s i z e Use No. & s iz e Use (PTOkW) ( h r) (PTOkW) (h r ) 1-29.8 1-2 9 .8 214 157 Farm S iz e = 6 4 .3 H ectares 1-22.4 1 -2 2 .4 131 83 558.19 538.64 Oonbine S iz e = 4-Rcw H ighest Middle 1 -3 9 .5 1 -2 9 .8 231 225 1-47.0 1-29.8 230 266 1-22.4 1-22.4 186 119 476.39 436.78 1-53.7 1-32.8 230 276 5.31 4 .0 5 150.09 135.61 1-30.6 1-30.6 1-4 0 .3 1^40.3 26.63 22.63 5.34 4.05 129.58 115.74 Farm S ize = 108.9 H ectares 170 111 504.02 451.66 Oonbine S iz e = 8-Row Highest Middle 32.44 24.36 Farm S ize = 9 1 .9 H ectares Cbmbine S iz e = 6-Row H ighest Middle R otation. In itia l Labor Fuel and T b tal investm ent c o s ts o il machinery in c o s ts r e la te d machinery_________________________ T -------------------------------- ( $ /h a )----------------------------------- C arbine S ize = 2-Row H ighest Middle Ss 21.70 20.66 5.36 4.0 8 129.95 117.10 Farm S iz e = 124.2 H ectares 156 105 541.21 478.49 18.43 18.24 5.39 4 .1 0 133.76 119.85 c o s ts Table 5.2B T illa g e in te n s i t y le v e l Median Conpletion Dates fo r P lanting and H arvesting in S S R otation. T o ta l m achinery r e l a t e d c o s ts ($ /h a ) P la n tin g o p e ra tio n s H arv estin g o p e ra tio n s Soybeans Soybeans --(d ay s a f t e r s t a r t i n g d a te c o n s t r a i n t )- Ooirbine S iz e = 2-Row H ighest Middle 150.09 135.61 Farm S ize = 6 4 .3 H ectares 6 .4 6. 2 Oonbine S iz e = 4-Row H ighest Middle 129.58 115.74 Farm S ize = 9 1 .9 H ectares 8.2 8.2 Oonbine S iz e = 6-Row H ighest Middle 129.95 117.10 133.76 119.85 12.0 12.0 Farm S iz e = 108.9 H ectares 7 .6 9 .2 Combine S iz e = 8-Row Highest Middle 12.0 12.0 12.0 12.0 Farm S iz e = 124.2 H ectares 7 .0 9 .5 12.0 12.0 Table 5.3A T illa g e i n te n s i t y le v e l E ffec t o f T illa g e In te n sity on S iz e , Use and Costs o f F ie ld Machinery fo r _______ Machinery S iz e and Use T illa g e t r a c t o r s U tility tra c to rs No. & s i z e Use No. & s i z e Use (PTOkW) (h r) (PITDkW) (h r) 1-4 8 .5 1-29.8 1-2 9 .8 255 275 185 1-22.4 1-22.4 1-22.4 Farm S ize = 112.5 H ectares 278 239 214 423.76 390.50 440.86 1-74.6 1-2 9 .8 1 -2 9 .8 255 424 285 1-24.6 1-22.4 1-22.4 392 368 330 379.78 306.19 339.79 1-9 2 .5 1-33.6 1-3 3 .6 254 466 314 1-3 0 .6 1-3 0 .6 1-30.6 399 345 327 392.48 305.72 342.51 1-107.4 1-38.8 1 -4 4 .7 254 468 273 130.08 120.69 122.69 23.18 27.35 22.26 6 .2 0 4.8 4 3.88 114.68 102.47 101.59 1 -4 0 .3 1 -4 0 .3 1 -4 0 .3 18.83 22.49 18.53 6 .2 0 4 .8 7 3.93 113.69 97.98 99.06 Farm S iz e = 248.9 H ectares Oonbine S iz e - 8-Row H ighest Middle Lowest 6.18 4,84 3.88 Farm S ize = 214.1 H ectares Oonbine S iz e = 6-Row H ighest Middle Lowest 30.86 30.0? 25.00 Farm S ize = 173.2 H ectares Combine S ize = 4--Rcw H ighest M iddle Lowest S Rotation. In itia l Labor Fuel and T o ta l investm ent c o s ts o il machinery in c o s ts r e l a te d m achinery c o s ts -----------------------------------($ /h a ) ----------------------------------- Combine S ize = 2-■Row H ighest Middle Lowest c 365 318 318 404.22 319.63 365.30 15.39 18.73 14.85 6.2 3 4 .8 9 3.95 112.01 96.62 99.29 Table 5.3B T illa g e i n te n s i t y le v e l Median Cbnpletion Dates fo r P lan tin g and H arvesting in C S Rotation. T b ta l m achinery r e l a te d c o s ts ($ /h a ) P la n tin g o p e ra tio n s H arv estin g o p e ra tio n s Com Com Soybeans Soybeans ------------ (days a f t e r s t a r t i n g d a te c o n s t r a i n t )- Oonbine S iz e = 2-Row H ig h est Middle Lowest 130.08 120.69 122.69 Farm S iz e = 112.5 H ectares 8 .8 8 .0 7 .1 7 .2 5 .6 5 .6 114.68 102.47 101.59 10.4 11.2 9 .8 7 .5 7 .8 7 .8 113.69 97.98 99.06 10.4 11.6 10.5 7 .5 8 .2 8 .2 112.01 96.62 99.29 11.3 11.3 11.3 16.6 16.6 16.6 11.8 11.8 11.8 Farm S iz e = 248.9 H ectares Combine S iz e = 8-Row H ig h est Middle Lowest 16.1 16.1 16.1 Farm S ize = 214.1 H ectares Combine S iz e = 6-Row H ighest Middle low est 10.6 10.6 10.6 Farm S iz e = 173.2 H ectares Cbnbine S iz e = 4-Row H ighest Middle Lowest 1 5 .5 15.5 1 5 .5 9 .5 11.7 9 .5 7 .2 8 .2 7 .3 16.4 16.4 16.4 12.0 12.0 12.0 80 s e le c te d ; one f o r n o - t i l l p la n tin g o f corn and th e o t h e r f o r p la n tin g o f so ybeans. The o t h e r re a so n was t h a t a b ig g e r t i l l a g e t r a c t o r had to b e s e l e c te d t o p u l l t h e n o - t i l l p l a n t e r and i t co u ld n o t b e u t i l i z e d t o i t s c a p a c ity . 5 .1 .4 C o r n - f ie ld bean (C PE) cro p r o t a t i o n The MBTS was u se d f o r b o th c o m and f i e l d beans a t t h e HLTI. At t h e MLTI, c o m was grown u s in g t h e CHTS and f i e l d beans u s in g th e MBTS. I h e MLTI red u c ed t i l l a g e t r a c t o r power re q u ire m e n ts by ab o u t 31 p e rc e n t and t h e TMRC by ab o u t 13 p e rc e n t compared t o t h e HLTI, a s shown i n T ab le 5 .4 . R eduction in t h e TMRC f o r s m a lle r farm s i z e s was n o t a s much b e ca u se o f t h e h ig h e r la b o r c o s t s . At t h e LLTI, t h e NTTS was u se d f o r c o m , and f i e l d b ean s w ere r a i s e d u s in g t h e MBTS. T h is c au se d ab o u t 32 p e rc e n t re d u c tio n in t i l l a g e t r a c t o r s i z e and th e re b y about 8 p e rc e n t r e d u c tio n in th e TMRC. I n i t i a l in v estm en t in m achinery was r e l a t i v e l y h ig h a t th e LLTI b e c a u se more im plem ents w ere r e q u ir e d c cn p ared t o t h e HLTI. 5 .1 .5 O o ra-co m -soybean-w heat (C C S W) cro p r o t a t i o n T a b le 5 .5 i l l u s t r a t e s t h e e f f e c t o f t i l l a g e i n t e n s i t y f o r t h i s ro ta tio n . The MBTS was u se d f o r e v ery c ro p a t th e HLTI. At t h e MLTI c o m a f t e r c o m , soybeans and w heat w ere r a i s e d u s in g t h e CHTS b u t t h e MBTS was u se d f o r c o m a f t e r w heat. The MLTI red u ced t i l l a g e t r a c t o r s i z e by about 44 p e rc e n t and c o n seq u e n tly TMRC by about 13 p e rc e n t. Table 5.4A T illa g e i n te n s i t y le v e l E ffec t o f T illa g e In te n sity on S iz e , Use and C osts o f F ie ld Machinery fo r C PB R otation. _______ Machinery S iz e and Use T illa g e t r a c t o r s U tility tra c to rs No. & s iz e Use No. & s iz e u se (PTOkW) ( h r) (PTOkW) (h r) In itia l Labor Fuel and investm ent c o s ts o il in c o s ts m achinery_________________________ Cbnbine S ize = 2--Row H ighest Middle low est 1 -5 5 .9 1-38.8 1-38.0 352 454 364 1-29.8 1-22.4 1 -2 2 .4 1-96.2 1-66.4 1-65.6 352 456 367 348 379 344 332.11 295.56 338.56 2-64.1 1 -8 8 .0 1-105.1 381 458 360 1-55.2 1 -4 0 .3 1-40.3 369 405 406 305.08 268.75 300.83 2 -7 9 .8 1-108.9 2 -5 3 .7 385 459 365 6.87 6 .2 0 5.24 110.83 107.81 109.79 1-67.1 1-55.2 1 -5 8 .9 1-67.1 1-66.4 1-65.6 16.88 19.42 17.82 6.92 6.25 5.34 95.33 90.89 92.84 Farm S ize = 363.0 H ectares 439 450 466 272.71 245.05 273.52 Oonbine S iz e = 8-Row H ighest Middle Lowest 27.85 32.02 28.10 Farm S ize = 272.4 H ectares Oonbine S iz e = 6--Row H ighest Middle Lowest c o s ts Phrm S ize = 158.6 H ectares Cbnbine S iz e = 4-Row H ighest Middle lo w est T b ta l machinery r e la te d 19.37 15.35 14.23 7.04 6.28 5.56 92.10 81.45 84.36 Farm S iz e = 450.0 H ectares 444 457 509 276.04 238.95 250.22 15.74 12.45 16.04 6.94 6.28 5.41 88.36 76.83 80.95 Table 5.4B T illa g e i n te n s i t y le v e l Median Completion Dates fo r P lan tin g and H arvesting in C FB R otation. T b ta l m achinery r e l a t e d c o s ts ($ /h a ) P la n tin g o p e ra tio n s H arv estin g o p e ra tio n s Com Com F ie ld Beans F ie ld Beans -(days a f t e r s t a r t i n g d a te c o n s t r a i n t )- Farm S iz e = 158.6 H ectares Cbnbine S iz e = 2-Row H ighest Middle lo w e st 110.83 107.81 109.79 10.3 10.5 7 .6 Cbnbine S iz e = 4-Row H ighest Middle Lowest 95.33 90.89 92.84 92.10 81.45 84.36 10.1 10.1 8 .1 88.36 76.83 80.95 8 .8 8 .8 8 .8 5 .9 6 .8 6 .8 14.0 1 4 .0 14.0 11.5 11.5 11.5 Farm S iz e = 363.0 H ectares 11.2 10.7 12.6 8 .4 7.1 7 .3 14.0 14.0 14.0 13.4 13.4 13.4 Farm S iz e = 450.0 H ectares Cbnbine S iz e = 8-Row H ighest Middle low est 1 4 .0 14.0 14.0 Farm S iz e = 272.4 H ectares Oonbine S iz e = 6-Row H ighest Middle Lowest 5 .9 6 .9 6 .9 11.1 10.1 13.0 8 .3 6 .8 6 .8 1 3 .7 1 3 .7 1 3 .7 13.7 13.7 13.7 Tkble 5.5A T illa g e i n te n s i t y le v e l E ffe c t o f T illa g e I n te n s ity on S iz e , Use and C o sts o f F ie ld Machinery f o r C C S I R o tatio n . _______ Machinery S iz e and Use______ U tility tra c to rs T illa g e t r a c t o r s No. & s iz e Use No. & s i z e Use (FTCkW) (h r) (PTOkW) (h r) In itia l investm ent in machinery Labor c o s ts Fuel and o il c o s ts T b ta l m achiner r e l a te d c o s ts ( $ /h a )Oonbine S iz e = 2--How H ighest Middle Lowest 1-64.1 1 -3 6 .5 1 -2 9 .8 274 345 261 1 -2 2 .4 1 -22.4 1 -22.4 Farm S iz e = 158.6 H ectares 355 359 295 354.50 314.42 327.54 1-109.6 1-6 2 .6 1-4 4 .7 275 346 299 1 -3 2 .8 1 -3 0 .6 1-23.9 447 476 480 290.99 256.52 255.61 Oonbine S iz e = 6--How H ighest Middle low est 2 -7 5 .3 1-85.0 1 -5 8 .9 273 347 335 1—44.7 1 ^ 2 .5 1 -46.2 2 -9 0 .2 1-101.4 1-64.1 274 350 348 1 -5 3 .7 1 -5 2 .9 1 -4 0 .3 113.99 106.28 101.66 17.67 19.47 18.71 6 .2 3 5 .2 9 3.98 91.53 85.13 82.88 Farm S iz e = 371.1 H ectares 470 493 445 274.36 237.37 233.22 Oonbine S iz e = 8-How H ighest Middle Lowest 6 .2 0 5.26 3.98 Farm S iz e = 272.4 H ectares Cbnbine S ize = 4--How H ighest Middle lo w est 26.84 29.21 24.56 17.15 14.80 14.01 6 .2 5 5.31 4 .1 3 88.96 77.42 74.30 Farm S iz e = 446.0 H ectares 496 506 571 277.33 243.23 225.36 14.55 12.48 13.17 6 .2 8 5.34 4 .0 8 87.61 76.70 72.45 Table 5.5B T illa g e i n te n s ity le v e l Median Couplet ion Dates for P lan tin g and H arvesting in C C S W R otation. T o ta l m achinery r e l a te d c o s ts ($ /h a ) P la n tin g o p e ra tio n s Com Soybeans Wheat H arv estin g o p e ra tio n s Com Soybeans Wheat -(days a f t e r s t a r t i n g d a te c o n s tr a in t) ----- Combine S iz e = 2-How H ighest Middle low est 113.99 106.28 101.66 Farm S ize = 158.6 H ectares 10.7 10.8 9 .2 4 .4 4 .2 4 .2 Cbmbine S iz e = 4-Bow H ig h est M iddle Lowest 91.53 85.13 82.88 88.96 77.42 74.30 11.5 12.4 10.1 4 .7 5 .0 6 .2 87.61 76.70 72.45 7 .8 7 .8 7 .8 7 .4 7 .4 7 .4 9 .1 9 .1 10.1 14.0 14.0 14.0 9 .1 9 .1 9 .1 8 .7 8 .7 8 .7 Farm S ize - 371.1 H ectares 11.4 12.2 12.8 4 .7 5 .0 5 .3 Combine S iz e = 8-Bow H ighest Middle lo w est 14.0 14.0 14.0 Farm S iz e = 272.4 H ectares Contone S iz e = 6-Bow H ighest Middle Lowest 7 .8 7 .8 9 .0 10.4 10.4 10.4 14.3 14.3 1 4 .3 10.4 10.4 10.4 10.0 10.0 10.0 Farm S ize = 446.0 H ectares 11.4 12.0 11.9 4 .7 4 .8 6 .0 10.8 10.8 11.4 13.5 13.5 13.5 10.8 10.8 10.8 10.4 10.4 10.4 85 Reduct ion in th e TMRC was n o t a s nxich f o r s m a lle r farm s i z e s b e cau se o f th e h ig h e r la b o r c o s t a s s o c ia te d w ith s m a lle r t r a c t o r s . At t h e LLTI, c o m was r a i s e d u s in g NTTS, and soybeans and w heat u s in g CUTS. The LLTI red u ced th e t i l l a g e t r a c t o r s i z e by a s much a s 64 p e rc e n t and th e TMRC by about 17 p e rc e n t. But t h e re d u c tio n was n o t a s much in e v ery c a se b e ca u se in some c a s e s s e l e c te d t r a c t o r power c o u ld n o t be f u l l y u tiliz e d . T here was no s i z a b l e d i f f e r e n c e in m edian co m p letio n d a te s o f p la n tin g and h a r v e s tin g o p e ra tio n s among t h e t h r e e l e v e l s o f t i l l a g e i n t e n s i t y , a s shown in T able 5.5B . 5 .1 .6 O o m - c o m - f ie ld bean-w heat (C C FB W) cron rotation T ab le 5 .6 shows t h e e f f e c t o f t i l l a g e i n t e n s i t y f o r t h i s r o t a t i o n . The MBTS was u sed f o r ev ery c ro p a t t h e HLTI. At t h e MLTI, w heat and c o rn a f t e r c o m were r a i s e d u s in g t h e CUTS, and t h e MBTS was u se d f o r c o m a f t e r w h eat, and f i e l d b e a n s. T i l l a g e t r a c t o r power re q u ire m e n ts red u ced by about 35 p e rc e n t and th e re b y TMRC re d u c e d by about 9 p e rc e n t co n p ared t o t h e HLTI. At t h e LLTI, c o m was grown u s in g t h e NTTS, w heat u s in g t h e CUTS and f i e l d b e an s u s in g t h e MBTS. The u se o f th e LLTI red u ced t i l l a g e t r a c t o r s i z e by ab o u t 58 p e rc e n t and c o n se q u e n tly TMRC by about 12 p e rc e n t. 5 .1 .7 O o r a - w h e a t- a lf a lf a - a lf a lf a (C W A A) c ro p r o t a t i o n T ab le 5 .7 shows t h e e f f e c t o f t i l l a g e i n t e n s i t y f o r t h i s r o t a t i o n . The MBTS was u sed f o r each c ro p a t t h e HLTI. At t h e MLTI, wheat was Table 5.6A T illa g e i n te n s i t y le v e l E ffec t o f T illa g e In te n sity on S iz e , Use and C osts o f F ie ld Machinery for C C FB W R otation. _______ Machinery S ize and Use T illa g e t r a c t o r s U tility tra c to rs No. & s i z e Use No. St s i z e Use (PTCkff) (h r) (PTOkW) (h r) In itia l investm ent in m achinery Labor c o s ts Fuel and o il c o s ts T o ta l m achinery r e la te d c o s ts ( $ / h a ) --------------------------------------- Combine S ize = 2-Row H ighest Middle Lowest 1 -5 5 .9 1 -3 6 .5 1-29.8 335 428 363 1 -2 4 .6 1-22.4 1-22.4 Farm S ize = 158.6 H ectares 352 383 318 358.11 329.17 354.62 Conbine S iz e = 4-Row H ighest Middle Lowest 1-96.2 1-6 2 .6 1-41.8 334 429 478 1 -4 2 .5 1-37.3 1-28.3 2-6 4 .1 1 -8 2 .8 1 -5 2 .9 334 432 483 1-67.1 1-47.7 1 -3 8 .0 400 470 462 321.76 273.00 261.46 2 -7 9 .0 1-101.4 1-62.6 334 434 490 1-67.1 1-59.7 1 -4 7 .7 115.18 112.26 110.46 17.42 20.44 21.18 6.60 6.03 4.72 98.77 90.17 86.96 Farm S iz e = 363.0 H ectares 444 485 513 287.10 257.46 249.63 Corrbine S ize = 8-Row H ighest Middle low est 6 .5 2 5.93 4 .6 5 Farm S iz e = 272.4 H ectares Combine S ize = 6-Row H ighest Middle Lowest 27.92 31.80 27.75 18.41 15.74 16.83 6 .7 5 6.03 4.74 92.54 82.43 80.38 Farm S iz e = 450.00 H ectares 466 508 559 278.78 256.87 251.55 15.22 13.07 14.28 6 .6 5 6 .0 5 4 .7 9 87.52 80.28 78.80 Table 5.6B T illa g e i n te n s i t y le v e l Median ccn p letio n Dates fo r P lan tin g and Harvesting in T b ta l m achinery r e l a t e d c o s ts ($ /h a ) c P la n tin g o p e ra tio n s Com F ie ld beans Wheat C IB W R otation. H arv estin g o p e ra tio n s Corn F ie ld beans Wheat -(days a f t e r s t a r t i n g d a te c o n s t r a i n t )- Farm S iz e = 158,.6 H ectares Confcine S ize = 2-Row H ighest Middle low est 115.18 112.26 110.46 10.7 13.2 9 .2 3 .7 4 .3 3.9 98.77 90.17 86.96 10.7 13.7 13.8 3 .7 4 .3 5 .8 92.54 82.43 80.38 11.0 13.4 12.6 4 .0 4 .4 5 .7 87.52 80.28 78.80 7.4 7 .4 7 .4 4 .3 4 .3 4 .3 14.0 14.0 14.0 6 .2 6 .2 6 .2 8 .7 8 .7 8 .7 4 .9 4 .3 4 .3 14.0 14.0 14.0 7 .0 7 .0 7 .0 9 .8 9 .8 9 .8 7 .1 7.1 7 .1 10.4 10.4 10.4 Farm S iz e = 450,.0 H ectares Combine S iz e = 8-Row H ighest Middle Lowest 4 .9 4 .9 4 .9 Farm S ize = 363,.0 H ectares Cbntoine S iz e = 6-Row H ighest Middle Lowest 14.0 14.0 14.0 Farm S ize = 272,.4 H ectares Corrbine S iz e = 4-Row H i^ ie s t Middle low est 3.4 3 .4 3.4 11.0 13.4 11.9 4 .0 4 .5 5 .6 4 .9 4 .9 5 .3 13.5 13.5 13.5 Table 5.7A T illa g e in te n s ity le v e l E ffec t o f T illa g e In te n sity on S iz e , Use and Costs o f F ie ld Machinery fo r C W A A Rotation, Machinery S ize and Use T illa g e T ra c to rs U t i l i t y t r a c t o r s A lf a lf a h a rv e s tin g No. & s i z e Use No. & s i z e Use U n its o f U n its o f (PICkW) ( h r) (PTCkW) (h r ) mowera lfa lfa c o n d itio n e r t r a c t o r s & b a le r Farm S iz e = 234.3 H ectares Oorrbine S iz e = 2-How H ighest Middle L ow est 1 -8 4 .3 1-8 4 .3 1-4 5 .5 218 197 257 1 -3 6 .5 1 -3 6 .5 1 -2 2 .4 229 229 248 4 4 4 3 3 3 2 -6 2 .6 2 -6 2 .6 2 -4 4 .7 263 243 219 1-54.4 1 -5 4 .4 1 -2 3 .9 369 369 342 499.25 504.81 449.98 25.16 24.71 26.44 6 .1 5 5.91 5.02 138.13 137.96 128.72 Fhim S iz e = 332.7 H ectares Cbnbine S iz e = 4-Row H ighest Middle low est In itia l Labor Fuel T o ta l in v estim en t c o s ts and m achinery in o il r e l a te d m achinery c o s ts c o s ts -($/ha)- 6 6 6 3 3 4 466.41 469.92 450.40 24.39 23.80 25.01 6 .4 2 6 .1 8 5 .0 4 132.20 131.46 127.01 Table 5.7B T illa g e i n te n s i t y le v e l Median Conpletion Dates fo r P lan tin g and Harvesting in C W A A Rotation. T o ta l machinery r e l a te d c o s ts ($ /h a ) P la n tin g o p e ra tio n s Corn Wheat A lfa lfa H arv estin g o p e ra tio n s Com Wheat -(days a f t e r s t a r t i n g d a te c o n s tr a in t) ------Farm S ize = 234.3 H ectares Corrbine S iz e = 2-Row H ighest Middle Lowest 138.13 137.96 128.72 5 .6 5 .6 5 .2 9 .7 9 .7 9 .7 132.20 131.46 127.01 9 .7 9 .7 9 .7 10.0 10.0 10.0 Farm S ize = 332.7 H ectares Oonbine S ize = 4-Row H ighest Middle Lowest 3.4 3.4 4 .7 6 .0 6 .0 4 .5 8 .6 8 .6 10.5 4 .0 4 .0 5.1 8 .6 8 .6 8 .6 10.4 10.4 10.4 90 r a i s e d u s in g t h e CHI'S and t h e MBTS was u se d f o r c o rn and a l f a l f a . The a v a i l a b l e f i e l d work tim e d u rin g t h e c o m p l a n t i n g se a so n d e te rm in e d t h e s i z e o f t r a c t o r s f o r t h i s c ro p r o t a t i o n . S in c e t h e MBTS was u se d f o r c o rn a t b o th t h e h ig h e s t and m id d le l e v e l o f t i l l a g e i n t e n s i t y , m achinery s i z e rem ain ed t h e same. At t h e m id d le l e v e l o f t i l l a g e i n t e n s i t y , i n i t i a l in v e stm e n t in m ach in ery in c r e a s e d b e c a u se an a d d it i o n a l c h i s e l plow was r e q u i r e d b u t l a b o r c o s t s and f u e l c o s t s d e c re a s e d b e c a u se c h i s e l p lo w in g r e q u i r e s l e s s e n e rg y co n p ared t o m oldboard p lo w in g . The TMRC w ere a lm o st t h e same a t b o th l e v e l s o f t illa g e in te n s ity . At th e LLTI t h e t i l l a g e t r a c t o r was 46 p e r c e n t s m a lle r c o n p ared t o t h e HLTI b u t t h e TMRC w ere o n ly ab o u t 7 p e r c e n t l e s s th a n t h a t o f t h e HLTI. The r e d u c tio n i n t h e s i z e o f t i l l a g e t r a c t o r and i n t h e TMRC f o r t h e 3 3 2 .7 h e c t a r e farm s i z e a t t h e LLTI was l e s s co n p ared t o t h e 2 2 3 .4 h e c t a r e farm s i z e b e c a u se two e i g h t row p l a n t e r s w e re r e q u i r e d f o r t h e 3 3 2 .7 h e c t a r e farm s i z e . The p l a n t e r s , i n t u r n , r e q u i r e d two 4 4 .7 PTCkW t r a c t o r s w hich c o u ld n o t be u se d t o c a p a c i ty . 5 .1 .8 C o m - s o y b e a n - w h e a t - a lf a lf a - a l f a l f a (C S W A A) c ro p r o t a t i o n The e f f e c t o f t i l l a g e i n t e n s i t y on s i z e , u s e and costs o f f i e l d m achinery f o r t h i s r o t a t i o n i s shown i n T a b le 5 .8 . f o r e v e ry c ro p a t t h e HLTI. The MBTS was u se d At t h e MLTI, so y b ean s an d w heat w ere r a i s e d u s in g t h e CHI'S an d t h e MBTS was u s e d f o r c o rn and a l f a l f a . A 34 p e rc e n t r e d u c tio n in t i l l a g e t r a c t o r s i z e b u t o n ly a maximum o f ab o u t 3 .5 p e r c e n t r e d u c tio n i n t h e TMRC was c a u se d by t h e MLTI o v e r t h e Table 5.8A T illa g e in te n s i t y le v e l E ffe c t o f T illa g e In te n sity T illa g e t r a c t o r s No. & s iz e Use (PTOkW) (h r) chi S iz e , Use and C osts o f F ie ld Machinery fo r C S W A A R otation. Machinery S ize and Use U tility tra c to rs A lf a lf a h a rv e s tin g No. & s iz e Use U n its o f U n its o f (PTQkff) ( h r) new era lfa lfa c o n d itio n e r t r a c t o r s & b a le r Oombine S ize = 2-Row H ighest Middle Lowest 1-63.4 1 -4 1 .8 1-33.6 428 521 498 1-22.4 1-29.1 1-22.4 385 317 334 1 -8 9 .5 1-58.9 1 -4 7 .7 404 496 532 1-29.1 1-42.5 1-29.1 437 350 397 Labor Fuel c o s ts and o il c o s ts -($/ha)- T o ta l m achinery r e la te d c o s ts Farm S ize = 293.4 H ectares 4 4 4 3 3 3 341.67 330.80 340.14 27.01 27.43 27.33 5.98 5.49 4.82 112.33 108.33 109.34 Farm S ize = 416.0 H ectares Cbnbine S iz e = 4-Row H ighest Middle low est In itia l investm ent in m achinery 6 6 6 5 5 4 341.08 345.40 327.88 22.36 22.41 22.61 5.96 5.54 4 .8 7 106.60 106.50 101.68 Table 5.8B T illa g e in te n s ity le v e l Median Couplet ion Dates for P lan tin g and H arvesting in C S W A A R otation. T o ta l m achinery r e l a te d c o s ts ($ /h a ) P la n tin g o p e ra tio n s Com Soybeans Wheat H arv estin g o p e ra tio n s A lf a lf a Com Soybeans Wheat -(days a f t e r s t a r t i n g d a te c o n s t r a i n t) — Farm S ize = 293.4 H ectares Conioine S iz e = 2-Row H ighest Middle Lowest 112.33 108.33 109.34 8 .3 10.0 6 .7 5 .7 4 .6 5 .7 106.60 106.50 101.68 4 .2 5 .2 5 .7 10.4 10.4 10.4 11.0 11.0 11.0 10.4 10.4 10.4 10.9 10.9 10.9 10.4 10.4 10.4 Farm S ize = 416.0 H ectares Contoine S iz e = 4-Row H ighest Middle low est 11.0 11.0 11.4 8 .9 10.1 6 .7 6 .2 4 .5 6 .2 10.9 10.9 11.4 4 .2 5 .2 5 .7 8 .7 8 .7 8 .7 93 HLTI. The re d u c tio n in th e TMRC was sm all because a d d itio n a l im plem ents - a c h is e l plow and a s t a l k sh re d d e r - w ere re q u ire d f o r th e MLTI. At th e LLTI, corn was r a i s e d u s in g th e NITS, soybeans and wheat u s in g t h e CHTS and t h e MBTS was used f o r a l f a l f a . The LLTI reduced t i l l a g e t r a c t o r power re q u ire m e n ts by about 47 p e rc e n t. But th e maximum re d u c tio n in th e TMRC was o n ly about 4 .5 p e rc e n t b ecause o f th e n e c e s s ity o f a d d itio n a l im plem ents - n o - t i l l p l a n t e r , c h is e l plow, and s t a l k s h re d d e r. 5 .1 .9 C O rn -c o m -s o y b e a n -w h e a t-a lfa lfa -a lfa lfa (C C S W A A) crop r o t a t i o n T able 5 .9 i l l u s t r a t e s th e e f f e c t o f t i l l a g e i n t e n s i t y f o r t h i s ro ta tio n . The MBTS was u sed f o r each cro p a t th e HLTI. At th e MLTI, soybeans, w heat, and co rn a f t e r c o m were r a is e d vising t h e CHTS and t h e MBTS was used f o r c o m a f t e r a l f a l f a , and a l f a l f a . The MLTI red u ced t i l l a g e t r a c t o r s i z e by 43 p e rc e n t b u t th e re d u c tio n in th e TMRC was v e ry sm all becau se o f th e a d d itio n a l equipm ent re q u ire d f o r t h e MLTI. The median com pletion d a te f o r c o m p la n tin g o p e ra tio n was a ls o l a t e r f o r th e MLTI conpared t o th e HLTI (T able 5.9B ) b ecau se o f t h e s m a lle r t i l l a g e t r a c t o r . At th e LLTI, co m was r a i s e d u sin g th e NITS, soybeans and wheat u s in g th e CHTS, and t h e MBTS was used f o r a lfa lfa . T illa g e t r a c t o r s i z e reduced by about 49 p e rc e n t conpared t o t h e HLTI b u t th e re d u c tio n in th e TMRC was v e ry sm a ll. The re d u c tio n in th e TMRC was s m a lle r f o r t h e 408.3 h e c ta re farm s i z e conpared to t h e 238.4 h e c ta r e farm s i z e b ecau se an 8-row p l a n t e r was re q u ire d a t t h e MLTI w hereas f o r t h e HLTI a 4-row p l a n t e r was ad eq u ate. T&ble 5.9A T illa g e i n te n s i t y le v e l E ffe c t o f T illa g e I n te n s ity on S iz e , Use and C o sts o f F ie ld Machinery f o r C C S W A A R o ta tio n . Machinery S iz e and Use A lf a lf a h a rv e s tin g T illa g e t r a c t o r s U t i l i t y t r a c t o r s U n its o f Use U n its o f No. & s i z e Use No. & s i z e (PTOkW) (h r ) (PTOkW) (h r ) mowera lfa lfa c o n d itio n e r t r a c t o r s & b a le r Combine S iz e = 2-Row H ighest Middle Lowest 1-64.1 1 -3 6 .5 1 -2 9 .8 364 484 423 1-22.4 1 -2 3 .9 1-22.4 378 360 318 1-109.6 1 -6 2 .6 1 ^ 4 .7 350 469 468 1-32.8 1 -4 0 .3 1 -2 3 .9 464 404 517 la b o r c o s ts ------------------------ Fuel T o tal and m achinery o il r e l a te d c o s ts c o s ts r^/ha)-------------------------- Farm S iz e = 238.4 H ectares 3 3 3 2 2 2 Combine S ize = 4-Row H ighest Middle Lowest In itia l investm ent in m achinery 372.26 346.15 357.19 27.87 30.02 27.90 6 .1 5 5.51 4 .6 5 119.43 114.46 113.00 Farm S ize = 408.3 H ectares 5 5 5 4 4 4 330.43 325.31 307.42 20.98 21.70 23.05 6 .1 5 5 .5 4 4 .6 5 103.54 102.72 99.14 Thble 5.9B T illa g e i n te n s i t y le v e l Median Cbnpletion Dates fo r P lanting and H arvesting in C C S WA A R otation. T o ta l m achinery r e l a te d c o s ts ($ /h a ) P la n tin g o p e ra tio n s Com Soybeans Wheat H arv estin g o p e ra tio n s A lfa lfa Com Soybeans Wheat -(days a f t e r s t a r t i n g d a te c o n s tr a in t) -------------- Gonbine S iz e = 2-Row H ighest Middle low est 119.43 114.46 113.00 Farm S ize = 238.4 H ectares 10.5 13.1 9 .2 4 .5 4 .1 4 .2 Gonfoine S iz e = 4-Row H ighest Middle Lowest 103.54 102.72 99.14 7.8 7.8 9 .0 2 .9 3 .6 4 .0 14.0 14.0 14.0 7 .8 7 .8 7 .8 7 .4 7 .4 7 .4 9 .1 9 .1 9 .1 8 .7 8 .7 8 .7 Farm S ize = 408.3 H ectares 11.6 13.1 10.2 4 .7 4 .1 6 .2 9.1 9 .6 10.1 3 .2 3 .9 4 .7 14.0 14.0 14.0 96 5 .1 .1 0 C o m -c o m -fie ld b e a n - w h e a t- a lf a lf a - a lf a lf a (C C IB W A A) crop r o ta tio n T able 5.10 i l l u s t r a t e s th e e f f e c t o f t i l l a g e i n t e n s i t y f o r t h i s r o t a t io n . The MBTS was used f o r every cro p a t th e HLTI. At th e MLTI, th e CHTS was used f o r wheat and com a f t e r c o m , and th e MBTS was used f o r o th e r c ro p s. Hie MLTI caused about a 35 p e rc e n t re d u c tio n in t i l l a g e t r a c t o r power req u irem en ts conpared t o th e HLTI. But th e change in th e HURC was l e s s th an 4 p e rc e n t because c h is e l plow and s t a l k sh re d d er implements were re q u ire d a t t h e MLTI in a d d itio n t o th e implements re q u ire d f o r th e HLTI. At th e LLTI, th e NITS was used f o r c o m , th e CHIS f o r w heat, and th e MBTS f o r f i e l d beans and a l f a l f a . T illa g e t r a c t o r power requirem ents were reduced by about 46 p e rc e n t b u t th e change in th e IMRC was l e s s th an 5 p e rc e n t conpared t o th e HLTI because more implements were re q u ire d a t th e LLTI. 5 .2 E ffe c t o f Crop f b t a t io n Crop r o ta tio n s tro n g ly in flu e n c e s th e s i z e , u se , and c o s ts o f f i e l d m achinery. Both t r a c t o r power and h a rv e s tin g c a p a c ity a r e a f f e c te d . Machinery s iz e i s determ ined by th e amount o f work t o be done and th e f i e l d tim e a v a ila b le t o f i n is h th e work. Crop r o t a t io n in flu e n c e s th e amount o f work t o seme e x te n t because t i l l a g e req u ire m e n ts o f cro p s vary somewhat. However, th e a v a ila b le f i e l d tim e i s s tro n g ly a ff e c te d by crop r o t a t io n . In a d i v e r s if i e d crop r o t a t i o n th e work i s d i s t r ib u t e d o v er a lo n g e r c a le n d a r p e rio d and th e r e f o re s m a lle r m achinery i s re q u ire d . I f f o r a given amount o f work, a v a ila b le f i e l d tim e co u ld be doubled, Table 5.10A T illa g e in te n s ity le v e l E ffec t o f U l l a g e In te n sity on S iz e , Use and Costs o f F ie ld Machinery fo r C C IB W A A R otation. ___________________Machinery S iz e and Use_________________ T illa g e t r a c t o r s U t i l i t y t r a c t o r s A lf a lf a h a rv e s tin g No. & s i z e Use No. & s i z e Use U n its o f U n its o f (PTOkW) (h r) (PTOkW) ( h r ) mowera lfa lfa c o n d itio n e r t r a c t o r s & b a le r Combine S ize = 2-How H ighest Middle low est 1 -5 6 .7 1 -3 6 .5 1 -2 9 .8 428 541 526 1 -2 4 .6 1-22.4 1 -2 2 .4 370 404 341 Farm S ize = 238.4 H ectares 3 3 3 2 3 2 Combine S ize = 4-Row H ighest Middle Lowest 1 -9 6 .2 1 -6 2 .6 1—41.8 418 541 646 1 -4 2 .5 1 -3 7 .3 1 -2 8 .3 416 487 486 In itia l Labor R ie l T o tal investm ent c o s ts and m achinery in o il r e l a te d m achinery c o s ts c o s ts ------------ 1--------($ /h a )---------------------- 375.30 366.63 372.36 28.59 32.20 30.02 6 .3 8 5.96 5.09 120.19 120.93 118.36 Farm S iz e = 408.3 H ectares 5 5 5 4 5 5 350.94 324.97 316.99 20.93 23.40 24.69 6 .4 0 6.0 0 5.14 108.53 104.35 102.82 Table 5.10B T illa g e in te n s ity le v e l Median Completion Dates fo r P lan tin g and H arvesting in C C FB WA A Rotation. T o ta l machinery r e l a t e d c o s ts ($ /h a ) P la n tin g o p e ra tio n s Com F ie ld beans Wheat H arv estin g o p e ra tio n s A lf a lf a Com F ie ld beans Wheat -(days a f t e r s t a r t i n g d a te c o n s t r a i n t) -------- Faim S ize = 238.4 H ectares Cbrrfcine S iz e - 2-How H ighest Middle Lowest 120.19 120.93 118.36 10.6 13.2 9 .2 7 .6 4 .3 9 .2 108.53 104.35 102.82 2 .9 3 .6 4 .0 14.0 14.0 14.0 4 .9 4 .9 4 .9 7 .4 7 .4 7.4 6 .2 6 .2 6 .2 8 .7 8 .7 8 .7 Farm S iz e = 408.3 H ectares Obntoine S iz e = 4-Bow H ighest Middle Lowest 3 .2 3 .7 4 .2 10.7 13.7 13.8 3.7 4 .3 5 .8 3 .5 3 .7 4 .9 3 .1 3 .9 4 .8 14.0 14.0 14.0 99 t h e m achinery s i z e c o u ld be h a lv e d ; o r by k e ep in g m achinery s i z e c o n s ta n t, c ro p la n d a r e a u n d e r c u l t i v a t i o n c o u ld b e doubled. Ten d i f f e r e n t c ro p r o t a t i o n s shown in T ab le 4 .1 in v o lv in g c o m , soybeans, f i e l d b e a n s, wheat and a l f a l f a w ere s tu d ie d . D ata in T ab le s 5 .1 th ro u g h 5 .1 0 w ere re a rra n g e d a s shewn in T a b le s 5 .1 1 th ro u g h 5 .1 6 to i l l u s t r a t e t h e e f f e c t o f c ro p r o t a t i o n on f i e l d m achinery s i z e , u s e , and c o s t s a t t h r e e d i f f e r e n t l e v e l s o f t i l l a g e i n t e n s i t y . Com was a dom inant c ro p i n c ro p r o t a t i o n s shown in T a b le s 5 .1 1 th ro u g h 5 .1 3 and i t l a r g e l y d e te rm in e d th e s i z e o f m achinery. When c o m was t h e o n ly cro p in a c ro p r o t a t i o n , m achinery re q u ire m e n ts p e r u n i t a re a and th e r e f o r e TMRC w ere h ig h . By a d d in g o t h e r c ro p s t o t h e c ro p r o t a t i o n , a re a u n d er c u l t i v a t i o n can b e in c r e a s e d w ith o u t in c r e a s in g t h e s i z e o f m achinery. Crop a r e a h a rv e s te d by a g iv en s i z e o f caribine can alm o st be do ubled by fo llo w in g a C C S W r o t a t i o n i n p la c e o f a C C r o t a t i o n , w ith o u t c o n s id e r a b le in c r e a s e in t h e s i z e o f t r a c t o r powered m achinery, a s can b e se e n i r o n T a b le s 5 .1 1 th ro u g h 5 .1 3 . The a re a u n d er wheat and soybeans d id n o t r e q u ir e a d d it i o n a l h a r v e s tin g c a p a c ity b u t an a d d itio n a l g r a in h e a d e r was r e q u ir e d . The t i l l a g e t r a c t o r s i z e in c re a s e d somewhat, s in c e c ro p la n d a re a d o u b led , and t i l l a g e and p la n tin g p e rio d s o f c o m and soybeans o v e rla p p e d c o n s id e ra b ly . m ents on a p e r u n i t a r e a b a s i s w ere much l e s s . But power r e q u ir e ­ The TMRC reduced t o about tw o - th ir d s o f t h a t o f C C r o t a t i o n . When soybeans in th e C C S W r o t a t i o n w ere r e p la c e d by f i e l d b e a n s, a d d it i o n a l equipm ent f o r f i e l d bean h a r v e s tin g - f i e l d bean p u l l e r and p ic k -u p h e a d e r - w ere r e q u ir e d and t h e r e f o r e i n i t i a l in v estm en t in m achinery in c r e a s e d . P la n tin g p e r io d s o f c o m and f i e l d beans do n o t Tlililc 5.11A Crop ro la tlo n KffecL o f Crop A t t a t i u i tat S iz e , ( t o , and f i n i s o f F ie ld M achinery a t tile IlLTI f o r th o s e I k ila th m s In will t it Corn I s u 11 ml nan t Crop. F a ra s lz o (h a ) G n itin e (h r) T illa g e t r a c to r No, It s i z e Ik e (PIUcw) (h r) ttic liin e ry S iz e and Use U rilU y T r a c to r Al fa l fa lia rv e s t I m; Uni I s o f U n its o f No. It s i z e Use (h r) nuw ara lfa lfa (PIChW) c o n d it lo n e r t r a c t o r It Im le r In v estm en t in n u c ltin e ry Labor c o s ts Fuel and o il o u s ts T o ta l nw rh in ery r e la te d c o s ts 160.28 At Ifaxiaun Crop Area H int enn be H a rv este d by a 2-Rwr (lirt)tn e C C S I 158 .6 142 228 C C 111 * 158 .6 201 1-55.9 1-64.1 1-55.9 C C S WA A 238.4 228 1-64.1 C 0 I ll W A A 238.4 206 1 -5 6 .7 79.3 — 581.96 31.03 7.01 355 — 351.50 26.84 6 .2 0 113.09 352 — 358.11 27.92 6 ,5 2 115.18 3 2 372.26 2 7 .8 7 6 .1 5 119.43 3 2 375.30 2 8 .5 9 6 .3 8 120.19 138.35 231 274 335 1-22.4 1-22.4 1 -2 4 .6 364 1 -2 2 .4 378 428 1-24.6 370 170 — At itlx ln u n Crop Area t h a t can b e H a rv e ste d by a 4-H lmt O jrb ln e C C 136.0 112 c r s i 272.4 c: c n i « 272.4 C C 3 * AA C C fB f A A — 507.72 21.52 7 .0 7 — 290.99 17.67 6 .2 3 91 ,5 3 — 321.76 17.42 6 .6 0 (IB. 77 330.43 2 0 .9 8 6 .1 5 103.51 350.91 2 0 .9 3 0 .4 0 108.53 1 -3 2 .8 277 275 1 -3 2 .8 447 331 1 -4 2 .5 400 — 1 -1 0 9 .6 350 1 -3 2 .8 461 5 1 -9 6 .2 418 1 -4 2 .5 416 S 4 4 1 -9 0 .2 170 2-15 1 -1 0 9 .6 221 1 -9 6 .2 4 0 8 .3 245 4 0 8 .3 220 100 c c T otal 5.11B Crop r o ta tio n Median Oorrpletion Dates fo r P la n tin g and H arvesting at th e HLTI fo r th ose R otations in which Cbm i s a Dominant Crop. T o ta l m achinery r e l a te d c o s ts ($ /h a ) P la n tin g o p e ra tio n s Com Soybeans or F ie ld beans Wheat H a rv estin g o p e ra tio n s A lf a lf a Cbm Soybeans or F ie ld beans Wheat ) ^Utlj o dJ. LivX kjLaJaXvXilg HiXLv* UUlUoUX At Maximum Crop Area t h a t can b e H arvested by a 2-Row Oonbine CC 166.28 11.1 CC S W 113.99 10.7 4 .4 7 .8 14.0 7 .8 7 .4 C C IB W 115.18 10.7 3 .7 3.4 14.0 4 .9 7 .4 C C S WA A 119.43 10.5 4 .5 7 .8 2 .9 14.0 7 .8 7 .4 C C IB W A A 120.19 10.6 7 .6 3.2 2 .9 1 4 .0 4 .9 7 .4 101 14.0 At Maximum Crop Area t h a t can be H arvested by a 4-Row Oonbine CC 14.0 138.35 11.9 C CS W 91.53 11.5 4 .7 9 .1 14.0 9 .1 8 .7 C C IB W 98.77 10.7 3 .7 4 .3 14.0 6 .2 8 .7 C C S WA A 103.54 11.6 4 .7 9 .1 3 .2 14.0 9.1 8 .7 C C IB W A A 108.53 10.7 3 .7 3 .5 3 .1 14.0 6 .2 8 .7 'Ih b le 5.I2A Crop ro t a lio n E r ie c l ( if Crop f ili a ti o n on S iz e , Use. and C o sts o f F ie ld M achinery a t th e W.TI f o r th o s e I t il n t ie i is in w hich Corn i s a ilnninant Crop. Farm siz e (lia) CLntolne Use (hi-) M achinery e ry S iz e and Use ty tra c to r A lfa) fa h a r v e s tin g Ut T il I age t r a c t o r No. & s i z e Use U n its o f U n its o f No. & s i z e Use n ew era l fa) fa (PTOkW) (h r) (PTOkW) (h r) c o n d itio n e r t r a c t o r & b a le r mi Investm ent Labor Fuel T b ta l in c o s ts and nnch in ery m u diinery o il r e la te d ____________________ c o s t s ______ c o s t s ----------------------------( 5 / h a ) ------------------------------ At Mix 1mm Crop Area t h a t can be H a rv este d by a 2-How C tntjlne Cc C C S I 142 228 201 228 205 191 315 428 484 541 1-22.4 1-22.4 1-22.4 1-23.9 1-22.4 235 359 383 360 404 — — — — — 3 3 — 2 3 35.78 29.21 31.80 30,02 32.20 5.63 5.26 5.93 5.51 5,96 149.12 100.28 112.26 374.46 26.39 256.52 273.00 325.31 324.97 19.47 20.41 21.70 23.40 5.66 5,29 6.03 5.51 6.00 116.49 85.13 90.17 102.72 104.35 496.21 314.42 329.17 346.15 366.63 114.46 120.93 At Maximm Crop A rea t h a t c an b e H a rv este d by a 4-It>w Conti I ne c c c c c c s w c fuw c S WA A c. c HI W A A 136.0 272.4 272.4 408.3 4 0 8 .3 142 245 221 245 220 1-37.3 1-62.6 1-62.6 1-62.6 1-62.6 266 316 429 469 541 1-29.1 1-30.6 1-37.3 1-40.3 1-37.3 314 — — — — 401 5 4 487 5 5 476 470 — „ 102 c c Hi W c c 3 WA A c c HI W A A 79.3 158.6 158.6 238.4 238.4 1-29,8 1-36.5 1-36.5 1-3G.5 1-36.5 Table 5.12B Crop r o ta tio n Median CoupletIon Dates fo r P lan tin g and H arvesting at th e MLTI fo r those R otations in which Corn i s a Dominant Crop. T b ta l m achinery r e l a te d c o s ts ($ /h a ) P la n tin g o p e ra tio n s Corn Soybeans or F ie ld beans Wheat H arv estin g o p e ra tio n s A lf a lf a Com Soybeans or F ie ld beans Wheat -(days a f t e r s t a r t i n g d a te c o n s t r a i n t )- At Maximum Crop Area t h a t can b e H arvested by a 2-How Combine 103 c c 149.42 10.5 c c s w 106.28 10.8 4 .2 7 .8 14.0 7 .8 7 .4 CCPBW 112.26 13.2 4 .3 3 .4 14.0 4 .9 7.4 Cc S wAA 114.46 13.1 4 .1 7 .8 3 .6 14.0 7 .8 7 .4 C C PB W A A 120.93 13.2 4 .3 3 .7 3 .6 14.0 4 .9 7 .4 14.0 At Maximum Crop Area t h a t can b e H arvested by a 4-How Oonbine 14.0 116.49 12.9 CCS W 85.13 12.4 5 .0 9.1 14.0 9 .1 8 .7 C C FB W 90.17 13.7 4 .3 4 .3 14.0 6 .2 8 .7 C C S WA A 102.72 13.1 4 .1 9 .6 3 .9 14.0 9 .1 8 .7 C C FB W A A 104.35 13.7 4 .3 3 .7 3 .9 14.0 6 .2 8 .7 CC T ab le 5 . 13A E f f e c t o f Crop R o ta tio n on S iz e , Use, and C o sts o f F ie ld M achinery a t tlie LLTI f o r ttia s e R o ta tio n s in which th i n i s a Ruminant Crop. Crop r o ta t io n Farm s iz e (h a ) Oatfclne" Use (h r) T illa g e tr a c to r No. & s i z e Use (PTOkW) (h r) M achinery S iz e and Use A lf a lf a h a r v e s tin g U tility tr a c to r No. & s i z e tlse U n its o f U n its o f (PTOkW) (h r) mowera lfa lfa c o n d itio n e r t r a c t o r & b a le r Investm ent in m achinery la b o r C o s ts Fuel and o il c o s ts ( $ /h a ) ----------- ibtnl rm chinery related c o s ts At Maxiaun Crop A rea t h a t can b e H arv ested by a 2-Row Q w b in e c c 79.3 142 1-29.8 128 1-22.4 119 — — 516.72 24.36 138.08 — — 327.54 24.56 3.98 101.66 27.75 4.65 110.46 c c s w 158.6 228 1-29.8 261 1-22.4 295 c C Fit W 158.6 201 1-29.8 363 1-22.4 31B — — 354.62 C C S WA A 238.4 228 1-29.8 423 1-22.4 318 3 2 357.19 27.90 4.65 113.00 C C FH W A A 238.4 205 1-29.8 526 1-22.4 341 3 2 372.36 30.02 5.09 118.36 At Maxlnun Crop A rea t h a t can b e H arv ested tiy a 4-Jlow C a rb in e CC 136.0 142 1-44.7 146 1-22.4 204 — — 424.08 17.99 3.71 115.00 CC s w 272.4 245 1 -1 4 .7 299 1-23.9 480 — — 255.61 18.71 3.98 82.88 — — 261.46 21.18 4 .72 86.96 C C FB W 272.4 221 1-41.8 478 1-28.3 462 C C S WA A 408.3 245 1-44.7 460 1-23.9 517 5 4 307.42 23.05 4.65 99.14 C C FB W A A 408.3 220 1-41.8 646 1-28.3 486 5 5 316.99 24.69 5.14 102.82 104 3.71 Table 5.13B Crop r o ta tio n Median Couplet ion Elates fo r P lan tin g and Harvesting at the LLTI fo r those R otations in which Cbm i s a Dominant Crop. T b ta l machinery r e l a t e d c o s ts ($ /h a ) P la n tin g o p e ra tio n s Com Soybeans or F ie ld beans Wheat H arv estin g o p e ra tio n s Cbm A lf a lf a Soybeans or F ie ld beans Wheat yuiXy^j a f t e r s t a r t i n g d a te c o n s tr a in t) ------- ----------- " At Maximum Crop Area t h a t can be H arvested by a 2-Row Oonbine CC 138.08 9 .2 C C S W 101.66 9 .2 4 .2 9 .0 14.0 7 .8 7 .4 C C FBW 110.46 9 .2 3 .9 3 .4 14.0 4 .9 7 .4 C C S WA A 113.00 9 .2 4 .2 9 .0 4 .0 14.0 7 .8 7 .4 C C IB W A A 118.36 9 .2 9 .2 4 .2 4 .0 14.0 4 .9 7.4 105 14.0 At Maximum Crop Area t h a t can be H arvested by a 4-Row Cbnbine CC 115.00 10.2 CC S W 82.88 10.1 6 .2 10.1 14.0 9 .1 8 .7 C C IB W 86.96 13.8 5 .8 4 .3 14.0 6 .2 8 .7 CCSWAA 99.14 10.2 6 .2 10.1 4 .7 14.0 9 .1 8 .7 102.82 13.8 5 .8 4 .9 4 .8 14.0 6 .2 8 .7 C C FB W A A 14.0 106 o v e rla p and t h e r e f o r e t i l l a g e t r a c t o r s i z e r e q u ir e d rem ained t h e same a s t h a t f o r C C r o t a t i o n even though t h e c ro p la n d a r e a was d o u b led . F i e l d la b o r c o s ts and f u e l c o s t s w ere more f o r C C FB W c ro p r o t a t i o n c o n p ared t o C C S W c ro p r o t a t i o n b e c a u se two d i s c in g o p e r a tio n s w ere r e q u ir e d f o r f i e l d b e a n s co n p ared t o o n ly o n e f o r so y b ean s; and f i e l d bean h a r v e s tin g r e q u ir e d an a d d i t i o n a l o p e r a t io n , f i e l d b ean p u l l i n g . By a d d in g two y e a r s o f a l f a l f a t o t h e C C S W c ro p r o t a t i o n , t h e a r e a u n d e r c u l t i v a t i o n c o u ld b e in c r e a s e d t o t h r e e tim e s t h a t o f C C r o t a t i o n w ith o u t i n c r e a s in g t h e s i z e o f c a r b in e s in c e d i f f e r e n t h a r v e s tin g m achinery i s r e q u ir e d f o r h a r v e s t i n g a l f a l f a . The p l a n t i n g seaso n f o r a l f a l f a does n o t o v e r la p t h e t i l l a g e se a s o n o f any o t h e r c ro p , t h e r e f o r e a l f a l f a c o u ld b e added t o t h e r o t a t i o n w ith o u t i n c r e a s in g th e s iz e o f tr a c to r ( s ) . Use o f t h e t r a c t o r ( s ) in c r e a s e d . H ie TMRC w ere h ig h e r th a n C C S W r o t a t i o n s i n c e t h e s e l e c t e d h a r v e s t i n g m achinery f o r a l f a l f a was n o t u t i l i z e d t o c a p a c ity . A gain, rep la c e m e n t o f so y b eans by f i e l d b e an s in c r e a s e d i n i t i a l in v e stm e n t i n m achin ery and c o n se q u e n tly t h e TMRC s l i g h t l y . T a b le s 5 .1 4 th ro u g h 5 .1 6 show t h e e f f e c t o f th o s e c ro p r o t a t i o n s i n w hich c o rn i s n o t a dom inant c ro p . w ith C C r o t a t i o n . T hese r o t a t i o n s w ere a l s o co n p ared M u ltic ro p r o t a t i o n s re d u c e d m achinery re q u irm e n ts on a p e r u n i t a r e a b a s i s and t h e TMRC o v e r t h a t o f s i n g l e c ro p ro ta tio n s . The amount o f r e d u c tio n v a r i e d w ith t h e l e v e l o f t i l l a g e in te n s ity . The re d u c tio n was more a t t h e HLTI and was l e s s a t t h e LLTI. The a r e a o f soybeans t h a t a g iv e n c c n b in e can h a r v e s t i n one se aso n i s l e s s th a n t h e a r e a t h a t t h e same com bine can h a r v e s t o f c o m , b e c a u se f i e l d tim e a v a i l a b l e f o r h a r v e s t i n g so y b e an s i s l e s s th a n t h a t f o r c o m . T hblo 5. HA Cnnj m l n tlim E f f e c t o f C rcp H o tu tlm cm 81*fi, U*?, and C o s ts o f F ie ld M achinery a t tin ; itt.TI f u r tlm so f t i t u t i u n s In w hich Q jrn I s n o t u llm iinnnt C ru|i. Farm s iz e (In) fiw b in e Ihe (h r) Ifac h ln eery ry S I____________________________________ iz e and Use U tility tra c to r A l f a lf a hgrvcM tlng T i l 1a g e t r a c t o r No. ti s i z e Use U n its o f I k i lt s o l No. k s i z e Use (PTOkW) (h r) muwera l f a l fa (PTOkW) (h r) c o n d lt l o n e r t r a c t o r ft b a l e r In v estm en t In n u c h in e ry la b o r c o s ts Fuel and o il c o s ts T b ta l m achinery r e la te d c o s ts — At UuxlmiT) Crop A rea t h a t con b e H a rv e ste d by a 2-Row C ontilne 7 9 .3 142 1 -5 5 .9 170 1 -2 2 .4 231 — — 581.96 3 4 .0 3 7.01 160.28 s s 6 4 .3 75 1 -2 9 .8 214 1 -2 2 .4 131 — — 558.10 32.4 4 5.31 150.09 c s 112.5 166 1 -4 8 .5 255 1 -2 2 .4 278 — — 42 3 .7 6 30.8 0 6 .1 8 130.08 c m 158.6 188 1 -5 5 .9 352 1 -2 9 .8 318 — — 332.11 2 7 .8 5 6 .8 7 110.83 C WA A 2 3 1 .3 155 1 -8 4 .3 218 1 -3 6 .5 229 4 3 4 9 9 .2 5 2 5 .1 6 6 .1 5 138.13 c s w AA 293 .4 231 1 -6 3 .4 428 1 -2 2 .4 385 4 3 341.67 27.01 5 .9 8 112.33 7 .0 7 138.35 At I h x ln u n Crop Area t h a t c a n b e H a rv e s te d by a 4-Itjw O u tlin e 130 .0 c c 142 1-9G .2 170 1 -3 2 .8 277 — — 507.72 2 1 .5 2 s s 9 1 .9 75 1 -3 9 .5 231 1 -2 2 .4 180 — — 4 7 6 .3 9 2 6 .6 3 5 .3 4 129.58 c s 173.2 161 1 -7 4 .6 255 1 -2 4 .0 392 — — 379.78 23.1 8 6 .2 0 114.68 2 7 2 .4 204 1 -0 6 .2 352 1 -5 5 .2 369 — — 365.08 16.88 6 .9 2 9 5 .3 3 332 .7 145 2 -6 2 .6 263 1 -5 4 .4 369 6 3 466.41 2 4 .3 8 6 .4 2 132.20 4 1 6 .0 213 1 -8 9 .5 401 1 -2 9 .1 437 6 5 311.08 2 2 .3 6 5 .9 6 1 06.GO C HI C IA A CSV AA 107 c c Table 5.14B Crop r o ta tio n Median Cbnpletion Dates fo r P lan tin g and H arvesting a t the HLTI fo r those R otations in which Corn i s not a Dominant Crop. T o ta l m achinery r e l a te d c o s ts ($ /h a ) P la n tin g o p e ra tio n s Com Soybeans or F ie ld beans Wheat H arv estin g o p e ra tio n s Corn A lf a lf a Soybeans or F ie ld beans Wheat -(days a f t e r s t a r t i n g d a te c o n s t r a i n t) — At Maximum Crop Area t h a t can b e H arvested by a 2-How Oonbine 166.28 11.1 c s 130.08 8.8 7 .2 15.5 10.6 C IB 10.3 5 .9 14.0 8 .8 C WA A 110.83 138.13 C S WA A 112,33 8 ,3 10.4 11.0 C C s s At Maximum Crop A rea t h a t can be H arvested by a 4-Row Oonbine 138.35 11,9 14.0 129.58 8 .2 12.0 C S 114.68 10.4 7 .5 16.1 11.3 C IB 95.33 10.1 5 .9 14.0 11.5 C WA A 132,20 6 .0 C S WA A 106.60 8 .9 150.09 14.0 6 .4 5 ,6 5 .7 6 .2 108 CC s s 12.0 9 .7 3.4 11.0 4 .2 * 9 .7 8.6 4 .0 8 .6 10.9 4 .2 8 .7 10.0 10.4 10.4 10.9 10.4 T ab le !..I5A Crop ro L u lIo n m o e L o f Crop f t . t a t i i n on S iz e , U se, nnd O k I s o f F ie ld M ichinery a t th e MU’! f u r th o s e Hit a t io n s in which Com i s n o t a U .n ln a n t Crop. Farm s iz e (h a ) G n iiin e Use (h r) T illa g e tr a c to r No. ft s i z e Use (h r) (PIOMf) M achinery S iz e and Use U tility tr a c to r A l l a l f a h a rv e s t lug M). ft s i z e Use U n its o f U n its o f (PTOkf) i( h r ) mowera lfa lfa c o n d it i o n e r t r a c t o r ft b a l e r Investm ent tn im rh ln e ry lnix>r c o s ts Fuel and o il c o s ts -------- ( J / h a ) ---------- T jlftl im rh ln e ry m in t e d c o s ts At Mnxlnun Crop A rea t h a t can b e H a rv e ste d hy a 2 - R » Q xrblne — 7 9 .3 142 1 -2 9 .0 191 1 -2 2 .4 235 S 8 0-1.3 75 1 -2 9 .8 157 1 -2 2 .4 83 49G.2I 3 5 .7 8 5 .6 3 149.42 — 538.61 2 4 .3 6 4 .0 5 135.61 C 3 112 .5 106 1 -2 9 .8 275 1 -2 2 .4 239 — C FU 156 .6 188 1 -3 8 .8 454 1 -2 2 .4 379 _ 300.50 3 0 .0 7 4 .8 4 120.09 — 295.56 32.02 6 .2 0 CI AA 2 3 4 .3 155 1 -8 4 .3 197 1 -3 6 .5 229 107.81 1 3 501.81 24.7 1 5.91 137.96 C 8 WA A 293.4 231 1 -4 1 .8 521 1-2 9 .1 317 4 3 330.80 2 7 .4 3 5 ,4 9 108.33 At K u tln u n Crop Area t h a t c a n b e H a rv este d by a 4-ltow O m b ln e C C 136.0 142 1 -3 7 .3 200 1 -2 9 .1 314 — — 374 .1 6 26.3 9 5 .6 0 116.40 S S 9 1 .9 75 1 -2 9 .8 225 1 -2 2 .4 119 — — 436 .7 8 2 2 .6 3 4 .0 5 115.74 C S 173 .2 161 1 -2 9 .8 424 1 -2 2 .4 368 _ _ 300.19 27 .3 5 4 .8 4 102.47 C Fll 272 ,4 204 1-0B.4 456 1^10.3 406 _ 268 .7 5 19.42 6 .2 5 90 .8 9 CIAA 332 .7 145 2 -6 2 .6 243 1 -5 4 .4 369 6 3 469.92 23 .8 0 6 .1 8 131.46 C S WA A 4 1 0 .0 213 1 -5 8 .9 496 1 -4 2 .5 350 6 5 345 .4 0 22.41 5.54 106.50 109 C C Table 5.15B Crop r o ta tio n Median Completion Dates fo r P lan tin g and H arvesting a t th e MLTI fo r th ose R otations in which Corn i s not a Dominant Crop. T o ta l m achinery r e l a te d c o s ts ($ /h a ) P la n tin g o p e ra tio n s Corn Soybeans or F ie ld beans Wheat H arv estin g o p e ra tio n s A lf a lf a Com Soybeans or F ie ld beans Wheat -(days a f t e r s t a r t i n g d a te c o n s t r a i n t) ----------------- At Maximum Crop Area t h a t can be H arvested by a 2-Bow Combine CC 149.42 s s 135.61 s 120.69 8 .0 5 .6 15.5 10.6 C FB 107.81 10.5 6 .9 14.0 8 .8 C WA A 137.96 5 .6 C S WA A 108.33 10.0 14.0 6 .2 4 .6 110 C 10.5 12.0 9 .7 3.4 9 .7 11.0 5 .2 10.4 10.0 11.0 10.4 At Maximum Crop Area t h a t can be H arvested by a 4-Row Combine C C 116.49 s s 115.74 Cs 102.47 11.2 7 .8 16.1 11.3 90.89 10.1 6 .8 14.0 11.5 C WA A 131.46 6 .0 C S WA A 106.50 10.1 C FB 12.9 14.0 8 .2 4 .5 12.0 8 .6 4 .0 8 .6 10.9 5.2 8 .7 10.4 10.9 10.4 T allin 5 . 16A Cnhi n i t n l ion B flu c l oT C n v R o ta ttc n cm S iz e , l b ; , und ( l i s t s o f F i e ld M achinery u t tlie LliTI f o r t li i s o f i l i a t i o n s In w hich C om i s n o t a U m in n n t Cnqt. Furm si a ; (h a ) th iiiiir a ibe (h r) __________ Mach in e ry S i ze and U T iU a g e t r a c t o r U tility - tra c to r ft). b s iz e Ib e k>. fa s i z e I b e (PlUtW ) (h r) (PTOkW) (h r) s e ___________ A1 fn l f a h a r v e st I U n its o f U n its o f ra w e ra lfa lfa c o n d it i o n e r t r a c t o r It b o l c r In v e s tn e n t In im e h in e ry la b o r c o o ts Fuel and o il c o s ts Hi till m achinery r e la te d a is ts = = 7 l7 fii)= = At t b x i n n Crop Area tlu it c an h e E b rv e s te d by a 2 - f tw C tn iiin e 7 9 .3 142 1-29.8 128 1-22.4 119 — — 518,72 24.30 3.71 138.08 1 )2 .5 166 1-29.8 185 1-22.4 214 — — 440.86 25.00 3.88 122.69 C H) 158.G 188 1-3 8 .0 364 1-22.4 344 -- — 338.56 28.10 5.24 109.79 C « AA 234.3 155 1-45.5 257 1-22.4 248 4 3 4-19.98 26.44 5.02 128.72 CS * AA 293.4 231 1-3 3 .6 498 1-22.4 334 4 3 310.14 27.33 4 .8 2 109.31 At ttucinun Crop Aren th a t can be Ib rv e s le d by a 4-ftwi Cbntilne c c 136.0 142 1-44,7 146 1-22.4 204 — — 424.08 17.99 3.71 115.00 c s 173.2 161 1-29.8 285 1-22.4 330 — — 339.79 22.28 3.88 101.59 C FB 272.4 201 1-65.6 367 1-40.3 406 — — 300.83 17.82 5.34 92.84 C wAA 332.7 145 2 -4 4 .7 219 1-2 3 .9 342 6 4 450.40 25.01 5.04 127.01 C S * AA 416.0 213 1-47.7 532 1-29.1 397 6 4 327.88 22.61 4.87 101.68 ill c c c s Table 5.16B Crop r o t a t io n Median Gonpletion Dates fo r P lan tin g and H arvesting at th e LLTI fo r th o se R otations in which Corn i s not a Dominant Crop. T o ta l m achinery r e l a t e d c o s ts ($ /h a ) P la n tin g o p e ra tio n s Cbra Soybeans or F ie ld beans Wheat H arv estin g o p e ra tio n s A lf a lf a Corn Soybeans or F ie ld beans Wheat a f t e r s t a r t i n g d a te c o n s t r a i n t) ------- At Maxinum Crop Area t h a t can be H arvested by a 2-Row Combine CC 138.08 9 .2 C S 122.69 7 .1 5 .6 15.5 10.6 C FB 109.79 7 .6 6 .9 14.0 8 .8 C WA A 128.72 5 .2 C S WA A 109.34 6 .7 5 .7 9 .7 4 .7 9 .7 11.4 5 .7 10.4 112 14.0 10.0 11.0 10.4 At Maximum Crop Area t h a t can be H arvested by a 4-Row Conbine C C 115.00 10.2 c s 101.59 9 .8 7 .8 16.1 11.3 92.84 8 .1 6 .8 14.0 11.5 C WA A 127.01 4 .5 C S WA A 101.68 6 .7 c FB 14.0 6 .2 10.5 5 .1 8 .6 11.4 5 .7 8 .7 10.4 10.9 10.4 113 But more f i e l d tim e i s a v a ila b le f o r prim ary t i l l a g e f o r soybeans compared to c o m . T h ere fo re , t i l l a g e t r a c t o r power req u irem en ts were le s s f o r S S r o ta tio n than f o r C C r o t a t io n . The TMRC were a ls o l e s s f o r S S r o t a t io n oonpared to C C r o ta tio n . Both p la n tin g and h a rv e s tin g seasons could be e n la rg e d by growing c o m and soybean cro p s in one r o t a t io n . A given combine could h a rv e st more crop a re a in one season b u t th e h a rv e ste d a re a co u ld n o t be doubled because h a rv e s tin g seaso n s o f th e s e two crops o v e rla p . T illa g e t r a c t o r power req u irem en ts were a ls o reduced bu t n o t t o h a l f because p la n tin g seasons o f th e s e two crops a ls o o v e rla p . The TMRC were l e s s f o r C S r o ta tio n compared t o b o th C C and S S r o ta tio n s . Crop a re a h a rv e ste d by a given c a rb in e could be alm ost doubled o v e r t h a t o f C C r o ta tio n by fo llo w in g C IB r o ta tio n because th e h a rv e s tin g se aso n s o f c o m and f i e l d beans do n o t o v e rla p . T illa g e t r a c t o r power req u ire m e n ts can a ls o be h alv ed o ver t h a t o f C C r o t a t io n s in c e p la n tin g seasons o f th e s e cro p s a ls o do n o t o v e rla p . Oonpared t o th e C C r o t a t io n , th e TMRC in C IB r o t a t io n were o n ly about tw o -th ird s a t th e HLTI, th r e e - f o u r th s a t th e MLTI, and f o u r - f i f t h s a t th e H I T . The C S W A A r o t a t io n in c re a s e d m achinery u se and d e creased TMRC c o n sid e ra lb y compared to th e C C r o t a t io n , b u t n o t a s much as th e C IB r o t a t io n . The median com pletion d a te s f o r p la n tin g and h a rv e s tin g o p e ra tio n s o f co m were a ls o c o n sid e ra b ly e a r l i e r in t h i s crop r o t a t io n compared t o C C r o t a t io n . The C W A A r o t a t io n d id n o t d e c re a se th e TMRC a s much a s o th e r crop r o t a t io n s . The reason f o r t h i s was s h o rt tim e a v a ila b le f o r p la n tin g e a r ly v a r i e t i e s o f c o m which a re re q u ire d fo r t h i s crop 114 ro ta tio n . At th e m iddle and th e low est le v e l o f t i l l a g e i n te n s i t y , th e TMRC f o r th e C II' A A r o t a t io n were h ig h e r conpared to C C r o t a t io n . I t was so b ecau se in C W A A r o t a t i o n a t th e m iddle le v e l o f t i l l a g e i n t e n s i t y corn and a l f a l f a w ere r a i s e d u s in g t h e MBTS and a t th e low est le v e l o f t i l l a g e i n t e n s i t y a l f a l f a was r a i s e d u sin g th e MBTS and wheat u s in g t h e CUTS. The re q u ire m e n ts o f a d d itio n a l equipm ent f o r r a i s i n g d i f f e r e n t c ro p s u s in g d i f f e r e n t t i l l a g e sy stem s, in c re a s e d i n i t i a l in v estm ent in m achinery and c o n seq u e n tly th e TMRC. 5 .3 5 .3 .1 M achinery R equirem ents and C o sts T illa g e t r a c t o r power re q u ire m e n ts f b r every c ro p r o t a t i o n , t h e r e i s a c a le n d a r p e rio d d u rin g which t r a c t o r power re q u ire m e n ts a r e maximum. The amount o f th e work and th e a v a ila b le f i e l d work tim e d u rin g t h i s p e rio d d eterm in e th e s i z e o f t r a c t o r ( s ) and th e re b y th e s i z e o f t r a c t o r powered im plem ents. The s p r in g t i l l a g e p e rio d was t h e peak work season f o r most o f th e cro p p in g system s c o n sid e re d in t h i s s tu d y . As th e t i l l a g e i n t e n s i t y was d ecreased , th e amount o f work t o be done d u rin g th e peak work season a ls o d e crea se d , and c o n seq u en tly t h e t i l l a g e t r a c t o r power re q u ire m e n ts d e cre a se d , as can b e se en from F ig u re 5 .1 . S in ce c h is e l plow ing was p e rm itte d in f a l l and m oldboard plow ing was n o t p e rm itte d , th e a v a ila b le f i e l d work tim e d u rin g t h e peak work season was more f o r t h e CHI'S conpared t o th e MBTS. T his a ls o c au se d c o n s id e ra b le d e c re a se in th e t i l l a g e t r a c t o r power re q u ire m e n ts f o r th e MLTI and t h e LLTI. 115 0 .7 - TILLAGE IINTENSITY LEVEL: | 0 . 6- H ig h e st Q M iddle Lowest £ 0 .5 . 0 .4 - 0 .3 ' 0 . 2- 0 . 1- 0 ^ F ig u re 5 .1 E f f e c t o f T il l a g e I n t e n s i t y L evel and Crop R o ta tio n on T il l a g e T r a c to r Pcwer R equirem ents. 116 T i l l a g e t r a c t o r power re q u ire m e n ts f o r t h e S S r o t a t i o n w ere l e s s th a n f o r t h e C C r o t a t i o n a t th e HLTI b e c a u se more tim e was a v a i l a b l e f o r s p r in g t i l l a g e f o r S S r o t a t i o n , even though t h e amount o f t i l l a g e work was t h e same f o r b o th r o t a t i o n s . A v a ila b le f i e l d work tim e d u rin g p eak work se a so n an d t h e amount o f f i e l d work was t h e same f o r S S and C S r o t a t i o n s a t t h e HLTI. T h e re fo re , power re q u ire m e n ts w ere a ls o t h e same f o r b o th r o t a t i o n s . The p eak work se a s o n f o r C C and C FB r o t a t i o n s a t t h e HLTI was d u rin g t h e s p r in g t i l l a g e p e r io d o f c o rn . S in c e o n ly h a l f o f t h e work was r e q u ir e d t o b e f i n i s h e d d u rin g t h i s p e r io d f o r C IB r o t a t i o n c o n p ared t o C C r o t a t i o n , t i l l a g e t r a c t o r power r e q u ire m e n ts f o r C FB r o t a t i o n w ere a l s o o n ly h a l f o f t h a t f o r C C ro ta tio n . S i m i la r ly , t i l l a g e t r a c t o r pow er r e q u ire m e n ts f o r C C IB W r o t a t i o n w ere o n ly h a l f , and f o r C C FB If A A r o t a t i o n w ere o n ly one th ir d o f th a t fo r C C ro ta tio n . I b r c ro p r o t a t i o n s i n w hich w heat fo llo w e d so y b ean s, e a r l y v a r i e t i e s o f so y b ean s w ere r e q u ir e d and, t h e r e f o r e , f i e l d work tim e a v a i l a b l e f o r soybean p l a n t i n g was l e s s in t h e s e c ro p r o t a t i o n s c o n p ared t o C S r o t a t i o n . F o r t h i s re a s o n t i l l a g e t r a c t o r pow er re q u ire m e n ts f o r C C S W , C S W A A , and C C S W A A r o t a t i o n s d i d n o t d e c re a s e i n p r o p o r tio n t o t h e d e c re a s e i n t h e amount o f work d u rin g p eak work s e a s o n . Power re q u ire m e n ts w ere c o m p a ra tiv e ly h ig h f o r th e C W A A c ro p r o t a t i o n b e c a u se o f t h e s h o r t e r p l a n t i n g se a s o n f o r s h o r t se a s e n v a r i e t i e s o f c o m . 117 5.3.2 H arvesting machinery T illa g e i n t e n s i t y h as no d i r e c t in flu e n c e on s i z e , u se , and c o s ts o f h a rv e s tin g m achinery. B ut, crop r o t a t io n s tro n g ly in flu e n c e s th e maximum a re a t h a t a given combine can h a rv e s t d u rin g one season (F ig u re 5 .2 , and S e c tio n 5 .2 ) . Table 5.17 shows h a rv e s tin g c o s ts (m achinery, la b o r, and f u e l) a s a ff e c te d by crop r o t a t i o n and combine s i z e . H arv estin g m achinery in c lu d e s th e SP combine and any a d d itio n a l m achinery which was re q u ire d in a given r o t a t io n such a s corn h ead er, g ra in header, p ick -u p header, m ow er-conditioner, b a le r , o r a l f a l f a t r a c t o r s . Whenever u t i l i t y a n d /o r t i l l a g e t r a c t o r ( s ) w ere used f o r a l f a l f a h a rv e s tin g , t h e i r c o s t, p ro ra te d a cco rd in g t o th e tim e used, was a ls o in clu d ed in th e h a rv e stin g c o s ts . H arv estin g c o s ts were c o n sid e ra b ly l e s s f o r m u lti-c ro p r o ta tio n s (n o t in v o lv in g a l f a l f a ) th a n f o r s in g le -c ro p r o ta tio n s . R o tatio n s in v o lv in g a l f a l f a a ls o had c o n sid e ra b ly h ig h e r h a rv e s tin g c o s ts th an o th e r r o t a t io n s . la b o r and fu e l re q u ira n e n ts f o r th r e e c u ttin g s o f a l f a l f a w ere h ig h e r th an f o r one combining o p e ra tio n f o r o th e r c ro p s (T able 5 .1 7 ). Mach in ery c o s ts w ere a ls o high f o r a l f a l f a h a rv e s tin g . Combine u s e was maximized by s e le c tin g an a p p ro p ria te farm s i z e , however m achinery s e le c te d f o r a l f a l f a h a rv e s tin g could n o t always be used t o c a p a c ity . T h is was one reaso n f o r h ig h e r m achinery c o s ts f o r a l f a l f a h a rv e s tin g . F o r th e s in g le cro p e n te r p r is e s , h a rv e s tin g c o s ts f o r corn d e creased w ith an in c re a s e in combine s i z e . However, h a rv e s tin g c o s ts f o r soybeans in c re a s e d w ith an in c re a s e in combine 118 450, 425- 00MBINE SIZE: 400- ■ 2-ROW Q 4-ROW 375- g 6-ROW B 8-ROW 350325300- CROPLAND AREA (h a) 275250225200 - 175. ISO125100. 75. 50250- i ss F ig u re 5 .2 . s i § § E f f e c t o f Combine S iz e and Crop R o ta tio n on th e Maximum C ropland A rea t h a t a Combine can H arvest in one Season. T a b le 5 .J 7 H arv u stirm O u sts (5/t> a) a s A ffe c te d hy C iop I liitn titn and C tn M n e S iz e . Q iriblne S iz e Crop lu lu M o n M achinery 2 -ftn r la b o r R ie l T b ta l ____ _______ 4-Bwr hat j il n e r y L a b o r ' R ie l f a ta l _ _ _______ 6-Itaw M achinery la b o r f u e l T tatal _ _ _ _ _ _____ B-R jw tb c h tn e r y la b o r F uel T iiial 51.3 8 .9 1.8 61.9 44.7 5.2 1.8 51.6 43 .0 3 .9 1.8 49.6 43.3 3.1 1.8 48.1 s s 55.5 5 .8 1.2 62 .5 50.5 4.1 1.2 55.7 53.8 3.4 1.2 58.5 57.2 3.0 1.2 61.4 c s 41.6 7.3 1 .5 50.4 38.3 4 .0 1.5 44.4 39.5 3.7 1.5 44.6 41 .6 2.1 1.5 45.2 C III 31.2 5 .9 1.7 38.8 26.3 3.7 1.7 31.7 26.3 2.9 1.7 30.9 26.1 4 .7 1.7 32.5 CCS1 31.6 7.1 l.B 4 0.3 26.8 4 .5 1.0 32.9 26.3 3.6 I .6 31.4 26.9 2 ,9 1.6 31.4 C C HI * 34.0 6.4 1.7 43.0 28.7 4 .0 1.7 31.4 28.2 3.2 1.7 33.1 28.1 2 .6 1.7 32,3 CIAA 65.3 15.8 3.0 84.1 6 5.7 14.5 3.0 83.2 C 3 I AA 51.4 13.8 2 .6 67.8 52.5 12.4 2 .6 6 7 .5 CC S * AA 51.6 13.0 2 .5 67.1 48.1 11.2 2 .5 61.8 CCilllAA 53.0 12.5 2 .5 68.6 50.5 10.9 2 .5 6 3.9 119 c c 120 s i z e due to a g r e a t e r in c r e a s e in combine p u rc h a se p r i c e th a n in h a r v e s tin g c a p a c ity f o r so y b ean s. F o r m u ltic ro p e n t e r p r i s e s (ex c ep t C S W A A), h a r v e s tin g c o s ts c o n s id e ra b ly d e c re a se d when c a r b in e s i z e was in c re a s e d from 2 t o 4-row . A f u r t h e r in c r e a s e i n combine s i z e d id n o t change h a r v e s tin g c o s ts n o tic e a b ly . 5 .3 .3 M achinery in v estm en t The e f f e c t o f t i l l a g e i n t e n s i t y and cro p r o t a t i o n on i n i t i a l m achinery in v estm en t (IM I) i s i l l u s t r a t e d i n F ig u re 5 .3 f o r t h e maxiirun farm s i z e s t h a t a 4-row c o n b in e can h a rv e s t i n on e se a so n . In g e n e ra l, IMI d e c re a se d w ith a d e c re a s e in t i l l a g e i n t e n s i t y . I b i s d e c re a s e was more pronounced when t i l l a g e i n t e n s i t y was red u c ed f o r a l l c ro p s in a r o t a t i o n (C C, S S , C S ) , and was l e s s n o tic e a b le when t i l l a g e i n t e n s i t y was red u c ed f o r o n ly a few c ro p s in a r o t a t i o n (m ost n o ta b ly f o r r o t a t i o n s in v o lv in g a l f a l f a ) . Crop r o t a t i o n had a s tro n g e f f e c t on IMI. S in g le -c ro p e n t e r p r i s e s (C C, S S ) and C W A A r o t a t i o n had a h ig h e r IMI due m ainly t o h ig h e r h a r v e s tin g c o s t s . IMI was lo w e st f o r C JB , C C S W , and C C IB tf r o t a t i o n s b e c a u se th e s e r o t a t i o n s had a more e v e n ly d i s t r i b u t e d h a rv e s t and t i l l a g e work p a t t e r n . A c o u p le o f c o u n te r i n t u i t i v e r e s u l t s a p p ea r in F ig u re 5 .3 . F o r C W A A r o t a t i o n , t h e IMI a t t h e MLTI was h ig h e r th a n a t t h e HLTI, s in c e a d d it i o n a l im plem ents, a c h i s e l plow and a s t a l k s h re d d e r, w ere r e q u ir e d a t t h e MLTI. The IMI was h ig h e r a t th e MLTI a s conpared t o t h e HLTI f o r C S W A A r o t a t i o n a ls o . T h is happened b e ca u se a s m a lle r cn to to $ its. 5.3 e cn cn OI ? O Effect of T illage In te n sity Level and Crop R o ta tio n on I n i ti a l Machinery Investment for the Maximun Fan Sizes that can be Harvested by a 4-Row Combine. iiiiiiiiim m m iiim iiijiiiitiim iiim iiiiiiiiiiiiiiiiiiiim iiiiim iiiii CFB iiiiiiiiiiiiiim iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii HDD! lllllllllllllllllllltlllllllllllllllllllllllllllllllllll S' i w rt CCSff CCFBffr 219999999999915 CWAAL ......................................................................................... .. CSWAA lllllllllllllllllllllllllllllllllllllllllllllllllllillllllllll CCSffAA CCFBWAA iiilliiiiiiiiiiiiiiiiiiiiliilliliiiiiiliiiiiiiiiiiiiiiiiiill P ES & $• CD s TILLAGE INTENSITY LEVEL: Figure INITIAL MACHINERY INVESTMENT ($ /h a ) 122 t i l l a g e t r a c t o r a t th e MLTI l e f t le s s a v a ila b le p la n tin g tim e th ereb y re q u irin g a b ig g e r, 8-row, p la n te r , w hereas th e HLTI re q u ire d o nly a 4-row p la n te r . The h ig h e r IMI a t th e LLTI a s conpared t o th e MLTI f o r C C r o t a t io n was because an 8-row p la n te r was re q u ire d a t th e LLTI (due t o th e lcw er maximum speed lim it c o n s tr a in t f o r th e n o - t i l l p l a n t e r ) , whereas a 4-row p la n te r was re q u ire d a t th e MLTI. The IMI was h ig h e r a t th e LLTI th an a t th e MLTI f o r C S and C FB r o ta tio n s because an a d d itio n a l n o - t i l l p la n te r was re q u ire d a t th e LLTI. 5 .3 .4 T o ta l annual m achinery r e l a te d c o s ts The e f f e c t o f t i l a g e i n te n s i t y and cro p r o t a t io n on t o t a l annual m achinery r e l a t e d c o s ts (TMRC) i s i l l u s t r a t e d in F ig u re 5 .4 f o r th e maximum farm s i z e s t h a t a 4-row c a rb in e can h a rv e st in one seaso n . Machinery, la b o r, and f u e l c o s ts were c o n sid ere d . The r e s u l t s f o r TMRC fo llo w t h e g e n e ra l p a tt e r n o f IMI (F ig u re 5 .3 ) . t i l l a g e i n te n s i t y reduced TMRC. A re d u c tio n in For most cro p r o t a t io n s , th e d iffe r e n c e in TMRC was more between th e HLTI and th e MLTI th a n between th e MLTI and th e LLTI. T his p a tte r n i s s im ila r t o t h a t o f t i l l a g e t r a c t o r power req u irem en ts (F ig u re 5 .1 ) , Crop r o ta tio n s had a s tro n g e r in flu e n c e on TMRC th an t i l l a g e in te n s ity . The e f f e c t o f crop r o t a t io n on TMRC was g e n e ra lly s im ila r t o th e e f f e c t on IMI, alth o u g h th e v a r ia tio n in th e TMRC were s l i g h t l y l e s s pronounced th an in th e IMI. Figure 5.4 0 1 to 0 1 TOTAL MACHINERY RELATED COSTS ($ /h a ) M § § § 3 8 % 8 o —i____ i i____ i > i i to o 8i M £ i f-1 8 i Effect of T illage In te n sity Level and Crop R o ta tio n on Total Field Machinery Related Costs for th e Maximum Faim Sizes that can be Harvested by a 4-Row C a rb in e . 111 n 11ii 11111m11ii 11n n m 11n m n i i n i n i n rm T m i 111 h itti 11i t t t i ss cs CFB CCSff CCFBW OHM CSWAA OCSWAA CCFBWAA iiiiiiim iiiu iiiiiiiiiir nn iiiiim iiiiiiiiiiiiiiiiiT T T T T T nr m in m iiiin iiin im iin iim u i .. iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiniiii iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii mam iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii £ £ p i a & r+ (D iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiniii iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiu iiiiiiiiiiiiiiiii ■ iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiniiiiiiiiiiiiiiiiiiiiiiiiii 124 5 .4 F ie ld Labor Requirements T ab le 5 .1 8 shows annual f i e l d la b o r re q u ire m e n ts in hours p e r h e c ta re a s a f f e c te d by cro p r o t a t i o n and t i l l a g e i n t e n s i t y . F ie ld la b o r r e q u ir e ­ m ents w ere o b ta in e d by d iv id in g th e annual sum o f f i e l d work hours by sc h e d u lin g e f f ic ie n c y and th e n adding 30 p e rc e n t e x tr a la b o r f o r r e p a i r , o ff-s e a s o n m aintenance and m achine p r e p a r a tio n . H ie com puter program d e s c rib e d e a r l i e r s e l e c t s th e a n a l l e s t t r a c t o r s i z e t h a t can f i n i s h t h e a s s ig n e d amount o f work w ith in s p e c if ie d c a le n d a r d a te c o n s t r a i n ts . S in ce d a te c o n s t r a i n t s f o r f i e l d o p e ra tio n s o f each crop w ere k e p t c o n s ta n t a c ro s s a l l cro p p in g system s a s f a r a s f e a s i b l e , th e la b o r re q u ire m e n ts do n o t v ary much w ith a change in crop r o t a t i o n o r t i l l a g e i n t e n s i t y . However, s in c e f a l l c h is e l plow ing was p e rm itte d and f a l l m oldboard plow ing was n o t, more tim e was a v a ila b le to c c n p le te t i l l a g e o p e ra tio n s a t t h e MLTI conpared to th e HLTI. T h e re fo re , in g e n e r a l, la b o r re q u ire m e n ts were h ig h e r f o r th e MLTI conpared t o t h e HLTI. The d if f e r e n c e between th e la b o r re q u ire m e n ts a t t h e HLTI and t h e LLTI was n o t v e ry l a r g e f o r m ost o f th e crop r o t a t i o n s c o n sid e re d . F o r sa n e c ro p r o t a t i o n s , th e d e c re a se in la b o r re q u ire m e n ts was more f o r t h e HLTI th a n f o r th e LLTI when farm s i z e was in c re a s e d from th e maxinun a re a t h a t can b e h a rv e s te d by a 2-row c a rb in e t o t h a t c o rre sp o n d in g t o 4-row . For th e s e r o t a t i o n s a t t h e LLTI, even th e a n a l l e s t p e rm itte d t r a c t o r s i z e was b ig g e r th a n a c t u a l l y re q u ire d f o r farm s i z e s c o rre sp o n d in g t o 2-row c a r b in e . T able 5 .1 9 i l l u s t r a t e s f i e l d la b o r d i s t r i b u t i o n f o r an average (50 p e rc e n t p r o b a b i l i t y l e v e l ) y e a r a t in te n s ity . t h r e e d i f f e r e n t l e v e ls o f t i l l a g e M u ltic ro p r o t a t i o n s had a more even d i s t r i b u t i o n o f la b o r d u rin g t h e y e a r compared t o s in g le - c r o p r o t a t i o n s . For r o t a t io n s Table 5 .1 8 . Labor Requirements (h/ha) as A ffected by Crop Rotation and T illa g e In ten sity . Farm s i z e and t i l l a g e i n te n s i t y Crop R o tatio n OC SS CS CFB OCSff CCFBW CWAA CSWAA CCSWAA 293.4 8 .3 8 .4 8 .4 238.4 8 .6 9 .2 8 .6 238.4 8 .8 9 .9 9 .2 416.0 6 .9 6 .9 7 .0 408.3 6 .4 6 .7 7 .1 408.3 6 .4 7 .2 7 .6 CCFBWAA Combine S ize = 2-Row Farm s iz e (ha)* HLTI MLTI LLTI 79.3 10.5 11.0 7 .5 6 1 .3 10.0 7 .5 — 112.5 9 .5 9 .2 7 .7 158.6 8 .5 9 .9 8.6 158.6 8 .3 9 .0 7 .6 158.6 8 .6 9 .8 8 .5 261.3 7 .7 7 .6 8 .1 Cbnbine Size = 4-Row Farm s iz e (ha)** HLTI MLTI LLTI 136.0 6 .6 8 .1 5 .5 91.9 8 .2 7 .0 --- 173.2 7 .1 8 .4 6 .8 272.4 5 .2 6 .0 5 .5 272.4 5 .4 6 .0 5 .8 272.4 5.4 6 .3 6 .5 ♦Maximum crop a re a t h a t can b e h a rv e ste d by a 2-row combine. ♦♦Maximim c ro p a re a t h a t can be h a rv e ste d by a 4-row combine. 332.7 7 .5 7.3 7 .7 T blilo 5 .1 9 Lulxn- (min-week) D i s t r i b u ti o n d u r in g nn A verage {50 p e r e is it p r o b a b i l i t y l e v e l ) Yeur n t l l i r e e D if f e r e n t l e v e l s o l T i l l a g e I n t e n s i t y .* C m p_________ _ _ _ _ _ ________________________________ A p ril liny Jin n 1o 17 24 o l oe 15 55 59 (S R5 19 TTltlll 11*1 J u ly 26 S3 F o ~ l 7 j S 3T B eg in n in g d a t e o f th e week___________________ _______________________ Augiist S t u t m faer QetuGor (* ivenlirr 57 14 " 2 i S? ol 11 18 25 52 09 16 23 55 txi 7ii '2 0 H ig h e st l e v e l o f T ilI n g e I n t e n s i t y 1.5 1. 0 2 . 0 2 . 0 1.8 1.0 .4 c s 1.3 1. 0 2 . 0 2 . 0 1 . 5 2 . 0 2 . 0 1.0 1.0 1 . 0 1.0 1.5 1. 0 2 . 0 1.4 1.4 1. 2 1. 2 2 . 0 1. 8 1.0 1.0 1.5 1.4 2 . 0 2 . 0 1 . 8 2 . 0 .4 1. 0 1.0 1 . 0 1 . 0 .1 c m c c s « 1.0 1. 0 1.0 1.2 1.2 1.2 1.1 c c s s 1.0 1 . 0 1. 0 1 . 0 1 . 0 2 . 0 2 . 0 1. 5 1.4 2 . 0 1.7 1 . 5 1.2 C WA A 2.3 2. 5 2.4 CS • AA C C SIA A 1.3 1. 5 2 . 0 2 . 0 1.1 2 . 0 1.5 1.4 2 . 0 2 . 0 1.8 2 . 0 C C FD WA A 1.5 1.4 2 . 0 1.7 1. 5 1.2 .6 1.4 1.0 1.0 1.0 1.0 1.0 .2 1.0 1.0 1.0 1.3 1.3 .2 1.0 1.0 1.0 1. 0 1. 0 1.0 1.0 .8 .2 2.1 2.1 .2 1. 5 1.7 .8 • .6 1.2 1.2 1.2 1.1 .2 .6 1.2 1.2 1.2 l . l 1.2 1.2 1 .2 1.1 3,2 3. 2 .5 4.0 5.2 2.7 3.2 4. 4 2.R .3 1.0 4 . 0 4 . 1 2. 3 2 . 9 4 . 0 2. 2 2.1 2.1 .7 1.2 1.2 .4 5 . 3 3 . 8 1.0 1.0 .7 5 . 8 3 . 8 1.0 .8 4 . 0 3 . 8 2 . 2 1.4 4 . 0 1.9 1.9 2. 0 4 . 0 4 . 0 2. 3 1.4 4.0 3.6 .6 1.2 1.2 1.2 l . l 1.2 1.2 1.2 1.1 6 . 0 4.1 .7 .9 5. 2 4 . 5 .8 1.2 .3 M iddle l e v e l o f T il I n g e I n t e n s i t y CC 1.0 1.0 2.0 2.0 2.0 .3 2 . 0 2 . 0 1. 2 2 . 0 1.8 1. 0 1. 0 2 . 0 1.9 S S CS .2 .5 2.0 2.0 2.0 .5 .1 C FB 1.5 1. 0 2 . 0 2 . 0 1.4 1.4 1.2 2 . 0 1 .8 1.0 1.0 CCSK 1.5 1.4 2 . 0 2 . 0 2 . 0 1.7 C C Fit W 1.5 1.4 2 . 0 1 . 5 2. 0 1.4 1. 2 1.9 1.0 1.0 1.0 C IA A 2 . 3 2 . 5 2. 4 .5 1.0 1 . 0 C SIA A 1.3 .9 .4 5.1 4 . 2 C C S WA A C C IB » A A 1 . 5 1.4 1 . 9 1.4 2 . 0 1 . 7 .2 5 . 3 3.8 1. 6 1.6 1. 5 .3 .8 .1 1. 0 1.0 .2 1. 0 1. 0 .2 4. 0 4.3 2.6 2.9 .1 1 . 5 1.4 2 . 0 1. 5 2 . 0 1.4 1.2 5 . 9 3 . 2 1.0 1.0 .1 4 . 0 1.9 4 . 0 3 . 0 2 . 5 1.7 4.0 2.5 2.1 1.9 1.3 1.2 2. 8 2. 8 .4 2.1 2.1 1.7 2. 0 2.1 4.0 2.2 4 . 0 4 . 1 2 . 5 1.7 .7 2.1 2.1 2.1 2.0 .9 4.4 2.8 .5 .3 2. 0 2. 0 2. 0 2.6 2. 6 1.7 .3 1.3 1.3 1.3 1.2 2. 2 2. 2 2 . 0 1.0 4 . 0 5 . 2 2 . 7 3.2 6 . 0 4.1 .7 . 5 1.8 1.3 1 . 3 2.4 2.4 2.4 2 . 3 .1 2.1 2.1 .8 1.4 .5 .6 2 . 0 2. 0 2.0 1.9 2.1 1.9 1.3 1.2 126 c c ro *r .5 .3 T a b le 5 .1 9 (o u n tin u e d ) Cnip (litill l i d A p ril 10 Jim o 65 "12 IB 26 6T 1? 24 H p^Inning d a te o l t h e week August "Iff" i f 21'""31 07 _M 21 “25 Sententoer W ll O c to b er HovinEer 18” 25 02 ( T T f f T r on i i 5 ~ l 3 U w e s t lu v e l o f T i l lu g e I n t e n s i t y r c .5 .8 1 .0 1 .0 .0 1 .0 .4 .3 .5 1.0 1.4 .4 2 . 0 1 . 8 1.0 1.0 l . e 1 .6 1 .0 1.4 3 S C3 C FU CCS* c c m * C WA A C S WA A C C S WA A C CH IIA A .1 1.5 1.8 1.0 1 . 8 1.0 1.4 1.2 2.0 1.8 1.0 1.0 .5 1.0 1.2 1.8 .0 2 . 0 .8 1.0 1.0 1.0 1.0 1.1 2 . 6 2 . 6 1.7 1.0 1.0 1. 0 1 . 0 .3 .6 1.5 2 . 0 1.2 1.4 1. 3 1.3 1.1 2 . 0 1.9 1. 0 1. 0 6 . 9 3.4 .3 .9 1.8 .5 2 . 0 1 . 0 6 . 0 4.1 .0 2 . 0 .8 5 . 3 3. 8 .6 1.5 2 . 0 1.2 1.4 1.3 1. 3 1.1 6 . 0 4 . 0 1. 0 1.0 .2 .9 1.0 1.0 .5 1.0 1.2 1.6 .3 .2 1 . 0 1.0 .2 1 . 0 1. 0 .2 2 . 0 1.5 4 . 0 5 , 8 2 . 8 3.7 .3 4 , 4 2. 8 4 .0 5.6 2.7 2,0 4 . 0 4 . 3 2 . 8 2.1 .8 4. 4 2 . 8 .2 4 . 0 1.9 4.0 2.9 4 . 0 3 .3 2 . 9 1.9 *Fhr m ed /n m farm s i z e s t h a t c a n b e h a r v e s te d by a 4 -ro w c arib ln e. 1.3 1. 3 1.3 1.2 .2 2.4 2.4 1.1 1.5 1.7 2 . 5 2.4 .3 .4 .5 3.5 .6 2. 3 2 . 3 2.1 2. 3 2. 3 .6 2. 4 2.4 1.1 1.5 1.7 2. 5 2 .4 .9 1.7 .1 1.5 1. 5 1.5 1.4 .9 .2 1. 5 1.5 1.5 1.4 .1 20 128 in v o lv in g a l f a l f a , th e la b o r req u ire m e n ts were very h ig h d u rin g th r e e 2-week h a rv e s tin g seaso n s o f a l f a l f a . The v a r ia tio n in la b o r d i s t r i ­ b u tio n among v a rio u s crop r o t a t i o n s was more a t th e LLTI compared t o th e HLTI. 5 .5 F uel R equirem ents F ig u re 5 .5 i l l u s t r a t e s th e e f f e c t o f t i l l a g e i n t e n s i t y and crop r o t a t i o n on f u e l re q u ire m e n ts. amount o f work. Fuel re q u ire m e n ts a re r e l a t e d t o th e T h e re fo re , a s th e t i l l a g e i n t e n s i t y was d ecrea se d f o r each cro p r o t a t i o n , th e fu e l re q u ire m e n ts a ls o d e cre a se d . The f u e l re q u ire m e n ts a ls o changed w ith a change in crop r o t a t i o n because d i f f e r e n t amounts o f work a r e re q u ir e d t o grow d i f f e r e n t c ro p s . T able 5.20 shows t h e f u e l req u ire m e n ts f o r each crop under th o s e t i l l a g e system s which a r e used f o r t h a t c ro p . T ab le 5 .2 0 F u el R equirem ents ( l i t r e s / h a ) o f th e Crops. T illa g e system Com Soybeans Wheat F ie ld beans A lf a lf a (6 2 .6 ) 71.0+ 32.9 Moldboard plow 54.7 (6 0 .3 )* 4 5 .6 (5 1 .3 ) 4 5 .5 (5 0 .0 ) C h ise l plow 4 3 .8 (4 8 .3 ) 34.7 (3 9 .2 ) 3 7.4 (4 1 .9 ) N o -till 2 7 .2 (3 1 .7 ) ♦Nunfeers w ith in t h e b r a c k e ts re p r e s e n t f u e l req u ire m e n ts when p re c e d in g cro p was co rn . ■^Fuel req u ire m e n ts f o r p la n tin g and h a rv e s tin g o p e ra tio n s o f f i r s t cro p ^ y e a r. F uel req u ire m e n ts f o r o n ly h a rv e s tin g o p e ra tio n s o f second c ro p y e a r. to o _1_ CJl 7 0 -i Figure JUEL REQUIREMENTS ( l i t r e s / h a ) 5.5 ss cs iiniiiiiiiiiiiiimiiii . CFB OCSW Level OCFBW iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii CffM and Crop B o ta tio n iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiin iiiiiiiiiiii CSWAA .................................... OCSWAA hd □ S' ..................................................... . OCFBWAA L lllllllllllllllllllHllllllllllllllllllllllllllllllllll a & e ct> p. <9S c+ TILLAGE INTENSITY LEVEL: Effect of T illage In te n s ity on Fuel R equirem ents. OCI 130 5 .6 S e n s i t i v i t y A n a ly s is H ie C C S W r o t a t i o n and t h e HLTI w ere s e l e c t e d t o i l l u s t r a t e t h e i n f lu e n c e o f s e v e r a l im p o rta n t a s s n i p t io n s on f i e l d m achinery r e q u i r e ­ m en ts and c o s t s . To stu d y t h e e f f e c t o f a d e s ig n p a ra m e te r, e v e ry th in g was f i x e d e x c e p t t h e d e s ig n f a c t o r t o b e s tu d ie d , and c a l c u l a t i o n s w ere made f o r m ach in ery s i z e , u s e , and c o s t s . 5 .6 .1 E f f e c t o f d e s ig n p r o b a b i l i t y C a lc u la tio n s o f f i e l d m achinery s i z e , u s e , and c o s t s w ere made f o r 70, 80, and 90 p e r c e n t d e s ig n p r o b a b i l i t i e s . The r e s u l t s a r e shown i n T ab le 5 .2 1 . As t h e d e s ig n p r o b a b i l i t y was in c r e a s e d from 70 t o 90 p e r c e n t , a v a i l a b l e f i e l d work tim e d e c re a s e d and t h e r e f o r e , t h e a re a t h a t a g iv e n s i z e o f com bine c o u ld h a r v e s t a ls o d e c re a s e d . M achinery s i z e on a p e r u n i t c ro p a r e a b a s i s in c r e a s e d and m achinery u s e d e c re a s e d . T h e r e fo re , t h e i n i t i a l in v e stm e n t i n m achinery in c r e a s e d and c o n se q u e n tly TMRC a l s o in c r e a s e d . But t i m e l i n e s s c o s t s , a s r e f l e c t e d by m edian c o m p le tio n d a te s o f p l a n t i n g and h a r v e s t i n g o p e r a t io n s (T a b le 5 .2 1 B ), d e c re a s e d . Median c c n p le tio n d a te f o r c o rn p l a n t i n g d id n o t d e c re a s e when d e s ig n p r o b a b i l i t y was in c r e a s e d from 80 t o 90 p e r c e n t , b e c a u se t h e r e was no a p p r e c ia b le i n c r e a s e in t h e s i z e o f u t i l i t y t r a c t o r . S in c e w eekly f r a c t i o n s o f c a le n d a r days s u i t a b l e f o r f i e l d work w ere assum ed t o b e n o rm a lly d i s t r i b u t e d , th e d i f f e r e n c e in a v a i l a b l e f i e l d work tim e betw een 70 and 80 p e r c e n t d e s ig n p r o b a b i l i t y was l e s s th a n betw een 80 and 90 p e r c e n t d e sig n p r o b a b i l i t y . Table 5.21A Design p r o b a b ility (p e rc e n t) E ffe c t o f Design P ro b a b ility on S iz e , Use, and Cbsts o f F ie ld Machinery fo r C C S W Crop Rotation a t th e HLTI. Farm s iz e (h a)* Combine Use (h r) Machinery S iz e and Use T illa g e t r a c t o r U tility tra c to r No. & s i z e Use No. & s i z e Use (PIDkW) (h r) (FTOkW) (h r ) Investm ent in m achinery Labor c o s ts T o ta l m achinerj r e l a te d c o s ts — ($ /h a ) — Combine S iz e = 2-Row 294.2 272.4 241.2 265 245 217 1-108.1 1-109.6 2 -5 6 .7 ii Combine 70 80 90 301 274 238 1-6 3 .4 1-64.1 1 -6 5 .6 1 247 228 202 CO 172.0 158.6 140.8 301 275 236 1-22.4 1-22.4 1-2 2 .4 385 355 315 326.13 354.50 401.37 26.93 26.84 26.64 109.22 113.99 121.75 480 447 401 268.53 290.99 327.39 17.67 17.67 22.44 88.17 91.53 102.62 504 470 429 253.13 274.36 304.63 17.52 17.15 16.98 86.06 88.96 93.26 528 496 450 256.62 277.33 308.81 15.00 14.55 14.09 84.41 87.61 92.12 4-Row 1 -3 2 .8 1 -3 2 .8 1-32.8 Combine S iz e = 6-Row 70 80 90 394.2 371.1 339.9 281 265 243 2 -7 2 .3 2 -7 5 .3 2 -7 9 .0 302 273 238 1 -4 4 .0 1 -4 4 .7 1 -4 5 .5 Combine S iz e = 8-Row 70 80 90 465.4 446.0 412.0 274 263 243 2 -8 5 .8 2 -9 0 .2 2 -9 6 .2 301 274 237 1 -5 2 .2 1 -5 3 .7 1-55.2 ♦Maximum crop a re a t h a t can be h a rv e ste d by th e given s i z e o f corrbine. 131 70 80 90 Table 5.21B Median Completion Dates fo r P lan tin g and Harvesting Operations a t 70, 80, and 90 Percent Design P ro b a b ility Level fo r C C S ff Rotation at the HLTI. Design p r o b a b ility (p e rc e n t) T o ta l m achinery r e la te d ^ c o s ts P la n tin g o p e ra tio n s Com Soybeans Wheat H arv estin g o p e ra tio n s Corn Soybeans Wheat (days a f t e r s t a r t i n g d a te c o n s t r a i n t) ----------- 70 80 90 109.22 113.99 121.75 C arbine S ize 11.3 10.7 11.0 - 2-How 5 .8 8 .3 7 .8 4 .4 7 .1 3 .9 8 .3 7 .8 7 .1 7 .9 7 .4 6 .7 9 .8 9 .1 8 .2 15.2 14.0 12.4 9 .8 9 .1 8 .2 9 .4 8 .7 7 .8 10.9 10.4 9 .6 15.3 14.3 13.1 10.9 10.4 9 .6 10.6 10.0 9 .3 11.2 10.8 10.1 14.1 13.5 12.5 11.2 10.8 10.1 10.8 10.4 9 .7 132 15.2 14.0 12.4 Cbnbine S ize = 4-Row 70 80 90 88.17 91.53 102.62 12.5 11.5 11.5 5 .8 4 .7 4 .3 Conbine S ize = 6-Rcw 70 80 90 86.06 88.96 93.26 12.7 11.4 11.6 5 .8 4 .7 4 .4 Cbnbine S ize = 8-Row 70 80 90 84.41 87.61 92,12 12.0 11.4 11.6 5 .8 4 .7 4 .4 133 5 .6 .2 E ffe c t o f f i e l d working ho u rs p e r day F ie ld w orking h o u rs p e r day (IWH/D) f o r o nly t r a c t o r powered o p e ra tio n s w ere v a rie d , h o ld in g e v e ry th in g e ls e f ix e d . T able 5.2 2 shews t h e r e s u l t s when IWH/D w ere eq u al t o 8, 10, and 12. A d e c re a se in th e IWH/D cau sed a p r o p o r tio n a l in c re a s e in th e t r a c t o r s i z e and co n seq u en tly a p r o p o rtio n a l d e c re a se in th e t r a c t o r u se . Whenever an in c r e a s e in th e t r a c t o r s i z e was n o t p r o p o r tio n a l, i t was e i t h e r b ecau se th e s m a lle s t p e rm itte d t r a c t o r was s e le c te d , o r because a b ig g e r t r a c t o r was re q u ir e d in o r d e r t o p u l l a p l a n t e r t h a t i s m atched w ith combine s iz e and t h a t can com plete p la n tin g w ith in th e s p e c if ie d d a te c o n s t r a i n t s . I n i t i a l in v estm en t in m achinery in c re a s e d w ith a d e c re a se in t h e IWH/D due t o an in c r e a s e in th e s i z e o f t r a c t o r s and a s s o c ia te d m achinery. Whenever a d e c re a se in t h e IWH/D d id n o t cause an in c r e a s e i n t h e number o f t r a c t o r s , la b o r c o s ts d e cre a se d ; o th e rw ise la b o r c o s ts a ls o in c re a s e d . In most c a s e s , th e d e c re a se in la b o r c o s ts was n o t s u f f i c i e n t t o o f f s e t t h e in c r e a s e in annual m achinery c o s ts due t o a h ig h e r i n i t i a l in v e stm e n t. However, th e change in TMRC was s i z a b l e o n ly when a d e c re a se in th e IWH/D cau sed an in c r e a s e in th e number o f t r a c t o r s . 5 .6 .3 E f fe c t o f i d l i n g t i l l a g e t r a c t o r s d u rin g h a rv e s t Some t r a c t o r s may have t o be f r e e d f r a n t i l l a g e o p e ra tio n s d u rin g h a r­ v e s t b ecau se la b o r may n o t be a v a ila b le f o r t i l l a g e o p e ra tio n s o r t r a c t o r s may be engaged in h a u lin g o p e ra tio n s ( 3 .1 .3 ) . The e f f e c t o f k eeping "h" t i l l a g e Table 5 .2 2 . E ffec t o f F ie ld Working Hours per Day on S iz e , Use, and Costs o f F ie ld Machinery fo r C C S W Rotation at the HLTI. F ie ld working hours p e r day Machinery S iz e and Use T illa g e t r a c t o r U t i l i t y t r a c t o r No. & s i z e Use No. & s iz e Use (PIDkW) (h r) (PTOkW) (h r ) Investm ent in machinery Labor c o s ts T o ta l machinery r e l a te d c o s ts -($ /h a)— Contone S ize = 2-Row 1-96.2 1-76.8 1-64.1 183 229 274 1-29.1 1-23.1 1-22.4 289 346 355 Combine S ize = 4-Row 8 10 12 2 -8 2 .8 2 -66.4 1-109.6 182 227 275 1-47.7 1-40.3 1-32.8 340 383 447 119.62 115.27 113.99 365.37 335.17 290.99 17.35 19.77 17.67 104.92 103.07 91.53 Farm S iz e = 371.1 H ectares 3-75.3 2 -9 0 .2 2 -7 5 .3 182 228 273 2 -3 3 .6 1-60.4 1-44.7 291 424 470 Combine S ize = 8-Row 8 10 12 21.89 25.13 26.84 Farm S ize = 272.4 H ectares Combine S iz e = 6-Row 8 10 12 421.02 373.97 354.50 366.73 301.17 274.36 18.66 15.32 17.15 107.32 91.90 88.96 Farm S ize = 446.0 H ectares 3-90.2 2-108.1 2 -9 0 .2 182 234 274 2 -4 0 .3 1-60.4 1 -5 3 .7 304 448 496 375.85 295.64 277,33 15.8 13.15 14.55 106.95 88.76 87.61 134 8 10 12 Farm S ize = 158.6 H ectares 135 t r a c t o r s i d l e ( f r e e from t i l l a g e ) d u rin g h a rv e st on m achinery s iz e and c o s ts i s s i t u a t i o n s p e c i f i c . Depending upon th e peak work season power req u irem en ts and th e amount o f t i l l a g e work t h a t can be scheduled (based on d a te c o n s tr a in ts ) d u rin g any h a rv e s tin g seaso n , id lin g o f "n" t i l l a g e t r a c t o r s p e r o p e ra tin g h a rv e s te r may n e c e s s ita te an in c re a s e in t h e i r s iz e o r number; and consequently in TMRC. In C C S W r o t a t io n wheat t i l l a g e o p e ra tio n s have t o b e done sim u ltan eo u sly w ith soybean and corn h a rv e s tin g . Hie power req u irem en ts f o r autumn wheat t i l l a g e o p e ra tio n s were o n e -h a lf o f th o s e f o r sp rin g co m and soybean t i l l a g e o p e ra tio n s . thro u ghout th e wheat p la n tin g season. A 6 o r 8-row combine was used Hie t r a c t o r s t h a t were id le d due t o h a rv e s tin g o p e ra tio n s could n o t be used f o r th e wheat t i l l a g e o p e ra tio n s . Bor farm s i z e s corresponding t o 6 and 8-row combines, two t i l l a g e t r a c t o r s were re q u ire d . In t h i s c a se , id li n g o f one t r a c t o r p e r o p e ra tin g h a rv e s te r d id n o t a l t e r th e power req u ire m e n ts, s in c e th e s i z e o f th e one t r a c t o r was equal t o o n e -h a lf o f t h a t o f th e t o t a l t i l l a g e t r a c t o r power req u ire m e n ts. However, when two t r a c t o r s were id le d f o r each o p e ra tin g h a rv e s te r, an a d d itio n a l t r a c t o r o f eq u al s i z e was re q u ire d f o r autunn wheat t i l l a g e o p e ra tio n s (T able 5 .2 3 ). Two and 4-row combines were i d l e f o r p a r t o f th e wheat p la n tin g seaso n . T illa g e t r a c t o r s , id le d b ecause o f th e o p e ra tin g h a r v e s te r, co u ld be used d u rin g t h a t p e rio d f o r wheat t i l l a g e o p e ra tio n s . Thus, f o r faira s i z e s co rrespon ding t o 2 and 4-row c a rb in e s , an in c re a s e in t i l l a g e t r a c t o r power req u irem en ts coupled w ith an in c re a s e in th e minber o f t i l l a g e t r a c t o r s id le d p e r o p e ra tin g h a rv e s te r, was n o t a s g r e a t a s f o r farm s i z e s co rresp o n d in g t o 6 and 8-row c a rb in e s (T able 5 .2 3 ). Table 5 .2 3 . E ffe c t o f Id lin g T illa g e Tractors during Harvest on S iz e , Use, and Cbsts o f F ie ld Machinery fo r C C S W Crop R otation at th e HLTX. N uiber o f t i l l a g e t r a c t o r s id le d f o r each h a r v e s te r o p e ra tin g in th e f i e l d T illa g e t r a c t o r s i z e & u se NoT & s i z e Use (PTOkW) ( h r) 1-64.1 2 -3 2 .1 2 -9 1 .7 274 274 96 1-109.6 2 -5 5 .2 3-50.0 275 273 201 Oonbine S iz e = 6-Row 0 1 2 MCDW* 354.50 339.65 525.96 26.84 35.44 24.27 113.99 118.98 140.92 7.77 11.79 16.85 290.99 276.33 308.63 17.67 22.61 23.65 91.53 92.84 99.56 9.14 11.95 12.66 Farm S ize = 371 .1 H ectares 2 -7 5 .3 2 -7 5 .3 3 -7 5 .3 273 273 182 274.36 274.36 317.01 17.15 17.15 17.15 88.96 88.96 96.30 10.37 12.12 12.44 Farm S ize - 446 .0 H ectares Corrbine S iz e = 8-Row 0 1 2 T o ta l m achinery r e l a te d __________ c o s ts —--------------- ( $ /h a ) ---------------- ------ Farm S iz e = 272.4 H e ctares Combine S ize = 4-How 0 1 2 Labor c o s ts Farm S iz e = 158.6 H ectares Combine S iz e = 2-How 0 1 2 Investm ent in m achinery 2 -9 0 .2 2 -9 0 .2 3 -9 0 .2 274 274 182 277.33 277.35 318.96 14.55 14.55 14.55 ♦Median c a n p le tio n d a te f o r wheat p la n tin g , days a f t e r s t a r t i n g d a te c o n s tr a in t. 87.61 87.62 94.79 10.84 12.28 12.53 137 Median co m pletion d a te s o f h a rv e s tin g o p e ra tio n s were n o t a ff e c te d b ecau se no change was made in th e h a rv e s tin g system . Median com pletion d a te o f c o rn and soybean p la n tin g o p e ra tio n s was a ls o n o t a f f e c te d b ecau se u t i l i t y t r a c t o r s i z e d id n o t change. But median c o n p le tio n d a te o f wheat d r i l l i n g in c re a s e d a s th e nuntoer o f t r a c t o r s id le d p e r o p e ra tin g h a r v e s te r were in c re a s e d b ecause th e i d l i n g o f t i l l a g e t r a c t o r s o c cu rred d u rin g p la n tin g season o f wheat (T able 5 .2 3 ). 5 .6 .4 S e n s i t i v i t y t e s t o f m achinery c o s t f a c t o r s The e f f e c t s o f v a rio u s c o s t f a c t o r s u se d w ere s tu d ie d . c o s t f a c t o r s a r e g iv en in T able A .5. Assumed Cbst f a c t o r s w ere v a rie d , one a t a tim e , and t h e annual m achinery r e l a t e d c o s ts were c a lc u la te d . The r e s u l t s a r e shown in F ig u re 5 .6 f o r a 4 4 6 -h e c ta re C C S W farm a t th e HLTI. T h is f i g u r e i s p re s e n te d in th e form o f a h o r iz o n ta l l i n e nomograph. The e f f e c t o f v a ry in g any one f a c t o r on TMRC can be d e te r ­ mined by draw ing a h o riz o n ta l l i n e through th e new v a lu e and re a d in g t h e p e rc e n t o f th e o r i g i n a l TMRC on th e le f t- h a n d s c a le . l a s t p r i c e v a r i a ti o n s had th e g r e a t e s t e f f e c t on th e TMRC. A s h o r t o b so le sc e n c e l i f e a ls o in c re a s e d th e TMRC s u b s t a n t i a l l y , b u t a lo n g o b so le sc e n c e l i f e d id n o t d e c re a se th e TMRC c o n sid e ra b ly s in c e t h e t o t a l m achine u se approached w ear-o u t l i f e . S alvage v a lu e s o f th e o b s o le te m achines were assumed t o be 10 p e rc e n t o f t h e i r l i s t p r ic e . The t r a d e - i n l i f e o f m achines a ls o s i g n i f i c a n t l y a f f e c te d th e TMRC. A ctu al t r a d e - i n v a lu e s o f th e m achines were e stim a te d from th e d a ta g iv en by Hunt, 1977 (T able 4 .2 ) . was n o t s i z a b l e . The e f f e c t o f f u e l r a t e on t h e TMRC 130 r- 130 120 5 r 120 150 110 110 200 12 100 -100 . 9 8 10 90 90 80 70 F ig u re 5 .6 100 6 I n te r e s t r a t e , p e rc en t 12 O bsolescence l i f e , y e a rs 80 150 10 T rad e -in l i f e , y ears 50 4 .0 0 - 100 ---------- 3.25 — 50 Fuel r a t e , 2 00 p e rc e n t Labor r a t e , o f assumed v alu e $ /h r R ep air, p e rc e n t o f assumed v alu e 70 P ric e , p e rc e n t o f l i s t E ffe c t o f Machinery Cost F a c to rs on Annual C osts fo r a 446 H ectare C C S W Farm a t th e HLTI. 138 P ercen t o f t o t a l annual machinery r e la te d c o s ts 5.00 — 139 6. CONCLUSIONS In t h e c o u rs e o f c o n d u c tin g t h i s s tu d y , t h e fo llo w in g ite m s w ere acco m plished: 1. A com puter model t o d e sig n a f i e l d m achinery sy stem f o r cash c ro p farm s was d e v e lo p e d . The com puter model d e s ig n s a m achinery s y s ta n b a se d upon f i e l d work s p e c i f i c a t i o n s , f i e l d o p e ra tio n c a le n d a r d a te c o n s t r a i n t s , m achinery c a p a c ity r e l a t i o n s , and f i e l d work c o n d itio n s f o r a farm grow ing a m ix o f f i e l d c ro p s . The model s p e c i f i e s t h e s i z e and number o f each component, p r e p a r e s a d e t a i l e d week-by-week work s c h e d u le , g iv e s th e d i s t r i b u t i o n o f la b o r needs f o r o p e r a tin g m achines, c a l c u l a t e s f u e l re q u ire m e n ts f o r each o p e r a tio n , and makes d e t a i l e d c o s t a n a l y s i s o f t h e s e l e c te d m achinery s e t . 2. F i e ld m achinery re q u ire m e n ts f o r 29 m ajo r c a sh c ro p p ro d u c tio n sy stem s o f so u th e rn M ichigan were c a l c u l a t e d o v e r a ran g e o f farm s i z e s . 3. The in f lu e n c e o f t i l l a g e i n t e n s i t y and c ro p r o t a t i o n on c o s ts and re q u ire m e n ts o f m achinery, la b o r , and f u e l f o r f i e l d work was e v a lu a te d . 4. A s e n s i t i v i t y a n a l y s i s was made t o m easure t h e e f f e c t o f system d e s ig n p a ra m e te rs on m achinery re q u ire m e n ts and c o s t s . Cta t h e b a s i s o f t h i s s tu d y , t h e fo llo w in g can b e s a i d : Given reaso n ab ly a c c u ra te in p u t d a ta , th e computer model i s a b le t o s e l e c t ( in a com pletely autom atic manner) a re a so n a b le m achinery s e t f o r a farm growing a mix o f f i e l d c ro p s. As farm s iz e in c re a s e s , annual m achinery r e l a t e d c o s ts d ecrease a t a d e c re a sin g r a t e . Maximum re d u c tio n o ccu rs when farm s iz e i s in c re a s e d from th e maximum a re a th a t a 2-row combine can h a rv e st t o t h a t co rresp o n d in g t o a 4-row combine. The c c n p u te r model was used t o e v a lu a te th e in flu e n c e o f t i l l a g e in te n s i t y and crop r o t a t io n on c o s ts and req u irem en ts o f f i e l d m achinery. However, th e r e s u l t s o f th e model a r e only as r e l i a b l e as th e in p u t d a ta . Assuming t h a t th e in p u t d a ta were f a i r l y a c c u ra te , th e fo llo w in g c o n clu sio n s can be made re g a rd in g th e in flu e n c e o f t i l l a g e i n te n s i t y and crop r o t a t io n f o r M ichigan c o n d itio n s : a. The crop a re a t h a t can be h a rv e ste d in one season by a given s iz e o f combine i s g r e a t e r f o r ra u ltic ro p r o t a t io n s than i t i s fo r s in g le -c ro p r o t a t io n s . For Michigan c o n d itio n s, th e a re a h a rv e ste d by a given s i z e o f c a rb in e in one season can be alm ost doubled by fo llo w in g C IB, C C S W, o r C C IB If r o t a t io n r a t h e r th a n co n tin u o u s corn r o ta tio n ; and by adding two y e a rs o f a l f a l f a t o C C S W, C C IB If, o r C S W r o t a t io n , th e crop a re a can be alm ost t r i p l e d over t h a t o f contin u o u s corn r o t a t io n . b. T ra c to r power req u irem en ts f o r continuous corn r o t a t io n a t th e HUT a r e very h ig h in comparison t o o th e r cash crop p ro d u ctio n system s s tu d ie d . T ra c to r power req u irem en ts fo r 141 r o ta tio n s in v o lv in g a l f a l f a a re l e s s th an o th e r r o t a t io n s . The d iffe r e n c e in t r a c t o r power requireaosnts, on a u n it a re a b a s is , between th e HLTI and th e MLTI i s s u b s ta n tia l f o r a l l r o t a t io n s s tu d ie d , except C W A A; b u t th e d if f e r e n c e between th e MLTI and th e LLTI i s n o t very la r g e . c. H arv estin g c o s ts p e r u n it a re a a re h ig h e s t f o r r o t a t io n s in v o lv in g a l f a l f a , and a r e lcw est f o r C IB , C C S W, and C C IB I r o t a t io n s . S in g le -c ro p r o t a t io n s have low er h a rv e s tin g c o s ts th a n r o t a t io n s in v o lv in g a l f a l f a , b u t h ig h e r th an o th e r n u ltic r o p r o t a t io n s . d. The h a rv e s tin g c o s ts a re h ig h e s t f o r maximum farm s iz e s t h a t can be h a rv e ste d by a 2-row c a rb in e . In c re a s in g conbine s iz e from 2 to 4-row , d e c re a se s h a rv e s tin g c o s ts in every crop r o t a t io n . B ut, f u r t h e r in c re a s e in combine s iz e does n o t s i g n i f i c a n t l y change h a rv e s tin g c o s ts . However, th e h a rv e s tin g c o s ts d e crea se s l i g h t l y f o r a continuous c o m r o t a t io n , and in c re a s e s l i g h t l y f o r a continuous soybean r o t a t io n , when c a rb in e s i z e i s in c re a s e d beyond a 4-row s i z e . e. In g e n e ra l, th e u se o f each p ie c e o f m achinery in c r e a s e s as t h e number o f c ro p s in a cro p r o t a t io n in c r e a s e s . f. M ulticrop r o t a t io n s have a more even d i s t r i b u t i o n o f la b o r d u rin g t h e y e a r c o ip a re d t o s in g le -c ro p r o t a t io n s . However, th e annual la b o r req u ire m e n ts, on a u n it a re a b a s is ( h / h a ) , -a re not c o n sid e ra b ly a ff e c te d by th e crop r o t a t io n . For r o ta tio n s in v o lv in g a l f a l f a , t h e la b o r re q u ire m e n ts a r e v ery h ig h d u rin g th r e e 2-week h a rv e s tin g se aso n s o f a l f a l f a . The v a r i a ti o n in la b o r d i s t r i b u t i o n among v a rio u s cro p r o t a t i o n s was more a t th e LLTI compared t o th e HLTI. g. F uel re q u ire m e n ts d e c re a se w ith a d e c re a se in t i l l a g e i n t e n s i t y f o r ev ery cro p r o t a t i o n . But th e v a r i a ti o n in f u e l r e q u ir e ­ m ents among cro p r o t a t i o n s i s n o t s iz a b le . h. The le v e l o f t i l l a g e i n t e n s i t y does n o t have a s iz a b le in f lu e n c e on th e TMRC f o r r o t a t i o n s in v o lv in g a l f a l f a . F o r o th e r r o t a t i o n s , th e d if f e r e n c e in th e TMRC betw een th e HLTI and t h e MLTI i s g r e a t e r th a n th e d if f e r e n c e between th e MLTI and th e LLTI. Comparing th e MLTI w ith th e LLTI f o r m u ltic ro p r o t a t i o n s shows sm a ll c o s t advantages f o r th e LLTI. i. The TMRC a r e h ig h e s t f o r s in g le - c r o p r o t a t i o n s (C C, S S) and f o r a C W A A r o t a t i o n ; and a r e C C S W, and C C IB If r o t a t i o n s . lo w est f o r C IB , R o ta tio n s in v o lv in g a l f a l f a , e x ce p t C W A A, and C S r o t a t i o n have TMRC low er th a n s in g le - c r o p r o t a t i o n s b u t h ig h e r th a n C IB, C C S W, and C C IB W r o t a t i o n s . The fo llo w in g c o n c lu sio n s can b e drawn from th e s e n s i t i v i t y a n a ly s is : a. W ith an in c re a s e i n th e d e sig n p r o b a b i l it y , m achinery s i z e , m achinery in v estm en t and c o n seq u e n tly annual m achinery r e l a t e d c o s ts in c r e a s e , b u t m achinery u s e and tim e lin e s s c o s ts d e c re a se . 143 b. A d e c re a s e in th e f i e l d w orking hours p e r day f o r t r a c t o r powered o p e ra tio n s c a u se s a p ro p o r tio n a l in c r e a s e in th e s i z e o f t r a c t o r s and r e l a t e d im plem ents, and a p r o p o r tio n a l d e c re a s e in t h e u s e o f t r a c t o r s and t r a c t o r pow ered m achinery. M achinery in v estm en t and th e re b y annual m achinery r e l a t e d c o s t s in c r e a s e , b u t la b o r c o s t s d e c re a s e i f t h e number o f t r a c t o r s does n o t in c r e a s e . In m ost c a s e s , a d e c re a s e in la b o r c o s ts i s n o t s u f f i c i e n t t o o f f s e t t h e in c r e a s e in annual m achinery r e l a t e d c o s t s due t o h ig h e r m achinery in v e stm e n t. However, t h e change in annual m achinery r e l a t e d c o s ts i s s i z a b l e o n ly when a d e c re a s e in f i e l d w orking h o u rs p e r day r e s u l t s in an in c r e a s e in t h e number o f t r a c t o r s . c. The e f f e c t o f k e e p in g "n" t i l l a g e t r a c t o r s i d l e (fre e from t i l l a g e ) d u rin g h a rv e s t on m achinery s i z e and c o s t s i s s itu a tio n s p e c ific . Depending upon th e peak work seaso n power re q u ire m e n ts and th e amount o f t i l l a g e work t h a t can be sc h e d u le d (b a se d on d a te c o n s t r a i n t s ) d u rin g any h a r v e s tin g se a so n , i d l i n g o f "n" t i l l a g e t r a c t o r s p e r o p e r a tin g h a r v e s t e r may n e c e s s i t a t e an in c r e a s e i n t h e i r s i z e o r number; and c o n se q u e n tly in annual m achinery re la te d c o s ts . d. The m achinery c o s t f a c t o r s can b e p la c e d i n th e fo llo w in g o r d e r b a sed on t h e i r in f lu e n c e on annual m achinery r e l a t e d c o s ts : l i s t p r i c e , o b so le sc e n c e o r t r a d e - i n l i f e (w h ich ev er i s u se d f o r com puting d e p r e c ia tio n ) , r e p a i r c o s t s , la b o r r a t e , i n t e r e s t r a t e and f u e l r a t e . 7. SUGGESTIONS IUR FURTHER STUDY I t i s s u g g e s te d t h a t t h i s stu d y b e expanded in t h e fo llo w in g w ay s: 1. E n la rg e t h e model by in c lu d in g t r a n s p o r t a t i o n , d r y in g , s t o r a g e , an d m a rk e tin g c o n p o n e n ts, t o make t h e t r a d e o f f a n a l y s i s more c c n p le te . 2. In c lu d e o t h e r m a t e r i a l r e s o u r c e s - s e e d , f e r t i l i z e r , p e s t i c i d e , and su p p le m e n ta l i r r i g a t i o n ; c a p i t a l re q u ire m e n ts f o r la n d , and s h o r t - r u n o p e r a tin g e x p e n s e s ; a s w e ll a s rev e n u e from t h e s a l e o f c ro p s ; t o make a co m p lete econom ic a n a l y s i s o f e a c h c ro p p ro d u c tio n sy stem . 3. In c lu d e s o i l l o s s and o rg a n ic m a tte r e f f e c t s o f each c ro p p ro d u c tio n sy stem , t o g e t a more c o m p lete p i c t u r e o f t h e t r a d e o f f s among t h e s e l e c t e d c ro p p in g sy ste m s. 4. In c lu d e o t h e r i n p o r t a n t M ichigan c ro p s , l i k e s u g a r b e e ts and o a t s ; an d n e c e s s a ry f i e l d o p e r a tio n s f o r th o s e c ro p s . I t i s a ls o s u g g e s te d t h a t t h e model b e in p ro v e d b y : 1. E x p l i c i t l y in c lu d in g t im e li n e s s c o s t s i n t h e c o s t a n a l y s i s . T h is w i l l s i n p l i f y t h e com parison o f d i f f e r e n t c ro p p ro d u c tio n sy s te m s. 2. I n c r e a s in g th e a c c u ra c y o f t h e t r a c t i v e e f f i c i e n c y v a lu e s f o r v a r io u s f i e l d o p e r a tio n s . T h is w i l l im prove t h e e s tim a tio n o f p r o d u c t i v it y o f t h e f i e l d o p e r a tio n s . 3. In c lu d in g t h e c o n s t r a i n t s on a v a i l a b i l i t y o f la b o r . 144 145 4. In clu d in g four-w heel d riv e t r a c t o r s as a categ o ry o f t r a c t o r s . 5. Allowing th e s u b s titu tio n o f custom o p e ra tio n s as an a lt e r n a ­ t i v e t o ownership o f c e r t a i n p ie c e s o f equipm ent. 6. In tro d u cin g a t r a d e - o f f a n a ly s is between th e s iz e and nurrber o f t i l l a g e t r a c t o r s and u t i l i t y t r a c t o r s . B e tte r d a ta a re re q u ire d in th e fo llo w in g a re a s t o in c re a s e th e accuracy o f th e r e s u l t s : 1. H arv estin g c a p a c ity o f d i f f e r e n t s i z e s o f combine f o r each cro p . 2. A v a ila b le f i e l d work tim e f o r h a rv e s tin g o p e ra tio n s a t d i f f e r e n t p r o b a b ility l e v e ls . 3. A v a ila b le f i e l d work tim e f o r t i l l a g e o p e ra tio n s under d i f f e r e n t s o i l c o n d itio n s . 4. Fuel req u irem en ts f o r h a rv e s tin g o p e ra tio n s . 5. D ata f o r c a lc u la tio n o f machine p ro d u c tiv ity and m achinery c o s ts . 6. T im eliness c o s t d a ta f o r p la n tin g and h a rv e s tin g o p e ra tio n s o f d i f f e r e n t cro p s. APPENDICES APPENDIX A INPUT DATA T ab le A. 1 A-sramed F ie ld O p e ra tio n s a n d C a le n d a r Da to Q > n s tra ln ls . F ie ld o p e r a tio n .. .. v e s t lag Cbm ,1 0 1 1 /.* M bldboard Plybcnns SReat TitblP A .l ( c o n tin u e d ) F ie ld o jje rath w i P la n tin g Q im ,0 1 06 's r z ' Maltftjcttrd Plow Ti I l a c e System F ie ld 1Jeans A iy h e am M icat ,0 5 06 * '» '* ‘ T S 'B S ' ,0 5 O its e l Plow T i l l a g e System iSirn B iybeans NlC&t A 1 fn lfa 0 8 ," ,0 1 0 5,* ,0 5 06 H ,(M 0 5 , 7 (5T ’ 53 ) IbfidiefM n i tr o g e n ,0 6 0 6 , " (T 5 ~ T 3 ’ A|jply h e ib l c ld e ftiw c u l t i v a t e A l f a lf a c u t t i n g #3 Q ua ( 5 i" 5 S ) N o - lill p la n tin g Anhydrous an tn m la a p p li c a t io n n it s ' .0 5 06 * .0 6 0 6 ,’ ,0 3 01, ,0 4 (r r 06, 56} ,0 3 ,0 5 0 6 , " (T 5 " ^ 2 , ,0 5 0 6 , 29 ~ 2 6 ' .06 0 7 , " ‘T f l ' l o ' 04. ,0 1 0 5 , ,0 8 0 0 ," 'N o - t i l 1 t i l l a g e sy ste m , 'F i g u r e s w ith in b r a c k e ts r e p r e s e n t s t a r t i n g nnd eftdlng d a t e c o n s t r a i n t s o f t h e o p e r a tio n nrm th n w ith ' ~ g ^ g' )• 'S t a r t i n g and e n d in g d a t e c o n s t r a i n t s f o r c o m b e f o r e w h eat a r c S e p te H ie r 25 and O c to b er 16, r e s p e c t iv e l y . ''S t a r t i n g d a t e c o n s t r a i n t * s t a r t i n g d a te c o n s t r a i n t o f c o rn h a r v e s t i n g , e n d in g d a te c o n s t r a i n t ■ en d in g d a te c o n s t r a i n t o f p l a n t i n g o fio ru tlo n fo r th e fo llo w in g c ro p . 5Ebon s t a l k s a r e s h r a k te d o n ly I f fo llo w in g c r o p i s w h eat. 'P l s c i n g i s n o t done when t h e fo llo w in g c r o p I s w heat. 'E n d in g d a te c o n s t r a i n t f o r c o m b e f o r e w heat I s Hty 0 8 . 'I k u b l c l d p s a r e a p p lie d d u r in g t h e p l a n t i n g o p e r a tio n . ’E nding d a te c o n s t r a i n t f o r c o rn b e f o r e w heat 1 a Jta ie 19. " S t a r t i n g and e n d in g d a t e c o n s t r a i n t s f o r so y b ean s b e f o re w heat a r e S e p tc n b c r 18 and O c to b er 16, r e s p e c t iv e l y . 1 'B id in g d a t e c o n s t r a i n t f o r so y b ean s b e f o r e w heat i s o n e week e a r l y . " F e r t i l i z e r I s a p p lie d d u r in g th e p l a n t i n g o p e r a t io n . " i n c l u d e s t h e f i e l d bean p u l l i n g n p e r a tlo n . " h e r b i c i d e s a r e s p ra y e d b e fo re t h e d i s c h a m a r in g o p e r a t io n . , s ld s c h a rro w in g i s done tw ic e . " S t a r l i n g d a te c o n s t r a i n t o f tire h a r v e s tin g o p e r a tio n f o r th e p re c e d in g c ro p . " B i d i n g d a te c o n s t r a i n t f o r w heat a f t e r f i e l d b e an s i s O cto b er 9 . 1'S o p tm im r 25 f o r w heat a f t e r c o m , and S e p ta ib o r 18 f o r w heat a f t e r soybeans and w heat a f t e r f i e l d b e a n s. " k iiw in g -o u n d ltlo n ln g and b a li n g . " C h i s e l t i l l a g e e y s t a a I s u se d f o r c o m In M ichigan o n ly alien c o m fo llo w s c o m , o r so y b e a n s, o rf ie ld beans. " B i d i n g d a te c o n s t r a i n t f o r c o m b e f o r e w heat i n Miy 15. " i f th e o p e r a tio n wns n o t f i n is h e d d u r in g t h e f a l l , I t was d is c o n tin u e d on N bvenber 26 and was r o s u i r d on A p ril 10 In th e fo llo w in g s p r in g . 148 T able A.2A F ie ld Working Hours p e r Day Assumed f o r V arious F ie ld O p eratio n s. F ie ld o p e ra tio n Com h a rv e s tin g Soybean h a rv e s tin g F ie ld bean h a rv e s tin g Wheat h a rv e s tin g A lf a lf a h a rv e s tin g O ther o p e ra tio n s F ie ld work hours p e r day 9 8 7 6 9 12 T able A.2B Mean and Standard D eviation o f F ra c tio n o f C alendar Days S u ita b le f o r Non-H arvesting F ie ld O p eratio n s. Beginning d a te o f th e *eek Mo/Day Mean .0000 .0000 .0000 .0000 .0000 .0000 .0000 .0000 .0000 .0000 .0000 .0000 .0000 .0000 .2874** .2715 .3699 .4786 .5508 .6167 .6619 .6897 .6936 .6802 .6905 Standard d e v ia tio n .0000 .0000 .0000 .0000 .0000 .0000 .0000 .0000 .0000 .0000 .0000 .0000 .0000 .0000 .2626** .2819 .3029 .3139 .3140 .3139 .2965 .2876 .2829 .2791 .2658 S ta lk sh red d in g , f e r t i l i z e r sp read in g and sp ra y in g o p e ra tio n s* Mean S tandard d e v ia tio n .3262 .4032 .4984 .6032 .6817 .7413 .7920 .8316 .8071 .6834 .5135 .3754 .4510 .5092 .6152 .7112 .6222 .6841 .7175 .7476 .7675 .7817 .7817 .7714 .7818 .4610 .4787 .4793 .4688 .4587 .4335 .3810 .3262 .3056 .3458 .3893 .3979 .3653 .3265 .2999 .2737 .2566 .2437 .2340 .2180 .2046 .2004 .2096 .2135 .2031 149 1/02 1/09 1/16 1/23 1/30 2/06 2/13 2/20 2/27 3/06 3/13 3/20 3/27 4/03 4/10 4 /1 7 4/24 5/01 5/08 5/15 5/22 5/29 6/05 6/12 6/19 T illa g e , p la n tin g , c u ltiv a tio n and anmonia a p p lic a tio n o p e ra tio n s Table A.2B (continued) Mo/Day 6/26 7/03 7/10 7/17 7/24 7/31 8/07 8/14 8 /2 1 1 0 /0 2 10/09 10/16 10/23 10/30 11/06 11/13 1 1 /2 0 11/27 12/04 1 2 /1 1 12/18 12/25 S tandard d e v ia tio n .7127 .7437 .7508 .7468 .7341 .7357 .7381 .7349 .7215 .7064 .6817 .6357 .5976 .5889 .6088 .5929 .5397 .4516 .3786 .2889 .1968 .0936 .2509 .2498 .2574 .2526 .2409 .2301 .2410 .2658 .2878 .3058 .3074 .3231 .3349 .3564 .3691 .3870 .4004 .4013 .3895 .3353 .2504 .1342 .0 0 0 0 .0 0 0 0 .0 0 0 0 .0 0 0 0 .0 0 0 0 .0 0 0 0 .0 0 0 0 .0 0 0 0 .0 0 0 0 .0 0 0 0 Mean .7976 .8206 .8222 .8143 .8048 .8087 .8175 .8190 .8119 .8079 .7952 .7738 .7492 .7436 .7531 .7452 .7111 .6540 .5873 .5079 .3952 .2659 .1492 .0889 .1016 .1683 .2516 Standard d e v ia tio n .1849 .1740 .1754 .1741 .1710 .1686 .1737 .1876 .1984 .2048 .2063 .2174 .2385 .2595 .2671 .2699 .2792 .3001 .3254 .3314 .3265 .2792 .2339 .1993 .2425 .3227 .4103 ♦These o p e ra tio n s were a ssu re d to be f e a s ib le on fro zen s o i l ir r e s p e c tiv e o f snow co v er. ♦♦Includes f r a c tio n s o f p rev io u s two weeks. 150 8/28 9/04 9/11 9/18 9/25 Mean 151 T ab le A.2C Mean and S ta n d a rd D e v ia tio n o f S u ita b le Work Days f o r H a rv e s tin g O p e ra tio n s. B eginning d a te o f th e week, Mo/Day Mean S ta n d a rd d e v ia tio n 10/09 10/16 10/23 10/30 11/06 0 .7 5 0 .7 1 0 .6 5 0 .5 9 0 .5 1 0 .2 7 0 .2 8 0 .3 0 0 .3 2 0 .3 3 9 /1 8 9 /2 5 0 .5 0 0 .5 0 0 .5 0 0 .5 0 0 .4 0 0 .2 0 0 .2 0 0 .2 0 0 .2 0 0 .2 0 0 .2 5 0 .2 5 1 0 /0 2 0 .5 0 0 .5 0 0 .4 0 0 .4 0 0 .3 5 0 .3 5 0 .2 0 0 .2 0 0 .2 0 0 .2 0 Wheat h a r v e s tin g 7 /1 7 7/24 7 /31 0 .6 0 0 .6 0 0 .6 0 0 .1 3 0 .1 3 0 .1 3 A l f a l f a h a r v e s tin g 5 /29 6 /0 5 7 /10 7 /1 7 0 .6 0 0 .6 0 0 .6 5 0 .6 0 0 .6 0 0 .6 0 0 .1 5 0 .1 5 0 .1 3 0 .1 3 0 .1 5 0 .1 5 H a rv e s tin g o p e ra tio n Com h a r v e s tin g Soybean h a r v e s tin g 1 0 /0 2 10/09 10/16 F i e l d bean h a r v e s tin g 8 /28 9 /04 9 /1 1 9 /1 8 9 /2 5 8 /2 1 8 /2 8 152 T able A.3A O p e ra tio n Com h a r v e s tin g Soybean h a r v e s tin g Wheat h a r v e s tin g F i e ld bean h a r v e s tin g Assumed P r o d u c tiv ity Data f o r S e lf-P r o p e lle d CJorrbines. S iz e Speed (Km/h) F ie ld e ffic ie n c y (p e rc e n t) F i e ld c a p a c ity (h a /h ) 2 -FOY* 5 .2 3 ( 3 .2 5 ) + 70 0 .5 6 ( 1 .3 8 ) +‘ 4-HOW 4 .8 3 (3 .0 0 ) 65 0 .9 6 (2 .3 6 ) 6 -RCW 4 .4 3 (2 .7 5 ) 63 1 .2 8 ( 3 .1 5 ) 8 -HOW 4 .4 3 ( 2 .7 5 ) 60 1 .6 2 ( 4 .0 0 ) 3 .0 5 !!)♦♦ (10-FT ) 3 .9 6 m (13-FT ) 3 .9 6 m (13-FT ) 4 .8 8 m (16-FT ) 4 .0 2 (2 .5 0 ) 70 0 .8 6 4 .4 3 (2 .7 5 ) 70 1 .2 3 ( 3 .0 3 ) 5 .2 3 ( 3 .2 5 ) 70 1 .4 5 ( 3 .5 8 ) 5 .2 3 ( 3 .2 5 ) 65 1 .6 6 ( 4 .1 0 ) 4 .4 3 (2 .7 5 ) 75 1 .0 1 ( 2 .5 0 ) 4 .8 3 ( 3 .0 0 ) 75 1 .4 3 ( 3 .5 5 ) 5 .6 3 ( 3 .5 0 ) 75 1 .6 7 ( 4 .1 4 ) 5 .6 3 ( 3 .5 0 ) 70 1 .9 2 ( 4 .7 5 ) 4 .0 2 ( 2 .5 0 ) 70 1 .7 2 ( 4 .2 4 ) 12-ROW 3 .6 2 (2 .2 5 ) 67 2 .2 2 ( 5 .4 8 ) 16-ROW 3 .2 2 (2 .0 0 ) 65 2 .5 5 (6 .3 0 ) 16-ROW 4 .0 2 ( 2 .5 0 ) 63 3 .0 9 ( 7 .6 4 ) 3 .0 5 (10-FT ) 3 .9 6 m (13-FT ) 3 .9 6 m (13-F T ) 4 .8 8 m (16-FT ) 8 -ROW*♦* ♦ S iz e o f c o m h e a d e r ♦♦ S ize o f g r a in h e a d e r ♦♦♦Nunber o f row s t h a t c a r b in e p ic k s 15) +Speed i n nph _H'F ie ld c a p a c ity i n a c r e s /h o u r (2 .1 2 ) Table A.3B Assumed P rod u ctivity Data fo r Tractor Powered F ie ld Machines. F ie ld e ff ic ie n c y (p e rc e n t) T ra c tiv e e ff ic ie n c y ( f r a c tio n ) Machine D ra ft (N/m) O p eratin g speed Mininum Maximum (Km/h) (Km/h) Moldboard plow 11675 (800) 80 0.75 5.63 (3 .5 ) 8.05 (5 .0 )* * D isc-harrow 4086 (280) 85 0 .6 0 4 .8 3 (3 .0 ) 8.05 (5 .0 ) D isc 3648 (250) 85 0 .7 5 6 .7 6 (4 .2 0 ) 11.27 (7 .0 ) C h ise l plow 7297 (500) 80 0.75 5.63 (3 .5 ) 8.05 (5 .0 ) D isc harrow + drag 4670 (320) 85 0 .6 0 4 .2 2 (2 .6 3 ) 7.04 (4 .3 8 ) G rain d r i l l 1678 (115) 75 0 .6 0 4.02 (2 .5 ) 8.05 (5 .0 ) Bow c u lt i v a t o r 2189 (150) 80 0.60 4 .8 3 (3 .0 ) 8.05 ( 5 .0 ) Mower-condit ic n e r 3940 (270) 80 0.75 5.63 (3 .5 ) 8 .0 5 ( 5 .0 ) P la n te r 1713* (385) 60 0.60 4 .8 3 (3 .0 ) 8.05 (5 .0 ) Table A.3B (continued) 2402* (540) 60 0.75 4 .8 3 (3 .0 ) 6.44 ( 4 .0 ) Anmonia a p p lic a to r 1868* (420) 65 0.60 4 .8 3 (3 .0 ) 8.05 (5 .0 ) B aler** 5838 (400) 75 1 .0 4 .8 3 ( 3 .0 ) 8.05 (5 .0 ) B aler*** 3648 (250) 75 1 .0 4 .8 3 (3 .0 ) 8.05 ( 5 .0 ) R otary s t a l k chopper 2919 ( 200) 80 0.75 4.83 (3 .0 ) 9.66 (6 .0 ) F e r t i l i z e r sp re a d e r 438 (30) 70 0.75 8.05 (5 .0 ) 8.05 (5 .0 ) S p ray er 584 (40) 60 0 .7 5 9 .6 5 (6 .0 ) 9.65 (6 .0 ) F ie ld bean p u l l e r 1668* (375) 75 0.75 6.44 (4 .0 ) 6.44 (4 .0 ) ♦per row n o t p e r m eter o f w idth **when cro p y ie ld i s 2 to n /a c re ***when crop y ie ld i s 1 to n /a c r e +d r a f t in l b / f t speed in nph 154 P la n te r , n o - t i l l Tlilile A.4A A -ssintd S iz e and P r i c e D a ta f o r T r a c to r Itnw ircd F i e ld l t u i i i n c s . S iz e , no. o f b o tto m * P r i c e ($ ) 2 681 3 1006 4 2561 5 2987 6 3490 7 4317 8 50R3 Dim --harrow S iz e , 2 .0 0 ( 6 .5 8 ) 850 2 .4 4 ( 8 ,0 0 ) 932 2 .8 7 (9 4 2 ) 1105 3 .48 ( 1 1 .1 2 ) 2636 3.91 (1 2 .8 3 ) 2825 4 .3 1 (1 1 .2 5 ) 2937 5.21 (1 7 .0 8 ) 5469 5.61 (I8 .5 (J ) 5001 1.22 ( 4 .0 ) 700 1 .8 3 ( 6 .0 ) 900 2.41 ( 8 .0 ) 1161 3.0f> ( 1 0 .0 ) 1245 3 . GO ( 1 2 .0 ) 1456 4 .2 7 ( 1 4 .0 ) 1560 4 .8 8 ( 1 6 .0 ) 1654 5 .4 9 (1 8 .0 ) 2236 3 .0 5 ( 1 0 .0 ) 2984 3 .6 6 ( 1 2 .0 ) 3631 3,96 (1 3 .0 ) 3746 0 1715 8 2913 12 3911 12 14165 B 3900 hi (ft) P r i c e ($ ) (ill.s o l plow S I7/i, n (rt) P rlc e ($ ) P ric e ($ ) 2 .4 4 ( 8 .0 ) 2361 Row c u l t i v a t o r S iz e , no. o f rows** P ric e ($ ) 4 1277 ttn u ir-c i >nd 11 lo n e r S iz e , m P ric e ($ ) 2 .7 4 ( 9 .0 ) 4710 S iz e , n o . o f rows** P ric e ($ ) 4 4410 6 6460 8 8840 S i z e , n o . o f rows** P ric e d ) 4 5667 6 7877 8 10014 A im aiia a |i p l i c a t o r S i z e , n o . o f rows** P ric e ($ ) 3 2400 4 2700 5 3000 0 33UO 7 3600 H a le r S i z e , m+ P ric e ($ ) 2 .7 4 ( 9 .0 ) 4132 S iz e , m <«) P r i c e ($ ) 1.5 2 ( 5 .0 ) 816 2 .1 3 ( 7 .0 ) 1996 2 .7 4 3 .6 6 ( 1 2 .0 ) 2140 4 .1 2 ( 1 3 .5 ) 2474 Fort. 11 l i'o r s p r e a d e r S iz e , »* (« ) P ric e ($ ) 12.19 (4 0 .0 ) 1749 S p ra y e r S i z e , m+ ( ft ) P ric e d ) 6 .1 0 ( 2 0 .0 ) 1620 S t a e , no. o f rows** P ric e d ) 4 1352 6 1696 8 2252 G ra in ill i l l S iz e , m ( ft ) (It) P l a n te r P la n te r, ikj -1 111 (It) H ila ry s t a l k c lu |ip e r F lo lil fionn p u l l e r *0741" nT~?173(1"T fy ^ o F ffiK ] * * 0 .?6 m ( 2 .5 f t ) rows, (9.0) 2021 +/ l e l d Width covered in run 155 U iliR jnard plow T ab le A.4B Power group T r a c to r Power and P r ic e D ata Used f o r D eveloping R e g re ssio n E q u atio n 6 . Power ran g e , PTO kW (PTO HP) Make o f th e tra c to r Model o f th e tra c to r Power, PTO kW (HP) P ric e , ($ ) 1 2 2 .4 -2 9 .8 (30-40) Ib rd Deutz MF* IH** BA 113C D 3006 MF-230 364 2 3 .8 6 2 3 .8 6 2 5 .7 5 2 6 .8 5 32 .0 0 ) 32.00) 34 .5 3 ) 3 6 .0 0 ) 6436 5813 6058 6700 2 2 9 .8 -3 7 .3 (40-50) Ib r d D avid Brown IH W hite CA 113C 885 464 2-50 2 9 .8 3 32.21 33.12 3 4 .3 0 4 0 .0 0 ) 4 3 .2 0 ) 4 4 .4 2 ) 4 6 .0 0 ) 7200 7116 8005 9118 3 3 7 .3 -4 4 .7 (5 0 -6 0 ) John D eere D eutz IH W hite 2240 D 5206 574 2-60 3 7 .5 6 38.78 3 9 .1 9 4 4 .0 0 5 0 .3 7 ) 5 2 .0 0 ) 5 2 .5 5 ) 5 9 .0 0 ) 8565 8878 9335 10685 4 4 4 .7 -5 2 .2 (60 -7 0 ) Ib rd Leyland D avid Brown MF LA 114C 272 1210 MF-275 4 4 .7 4 4 6 .2 3 4 9 .2 0 5 0.28 6 0 .0 0 ) 6 2 .0 0 ) 6 5 .9 8 ) 6 7 .4 3 ) 10463 9769 11032 10254 5 5 2 .2 -5 9 .7 (7 0 -8 0 ) John D eere W hite lo n g A llis-C h a lm e rs 2640 2-70 900 185 52.47 5 2.65 5 4.35 5 5.83 7 0 .3 7 ) 7 0 .6 0 ) 7 2 .8 8 ) 7 4 .8 7 ) 11234 11861 10147 12225 6 5 9 .7 -6 7 .1 (8 0 -9 0 ) David Brown MF Ib rd Deutz 1410 MF-285 FA 115M D 8006 6 0 .2 5 6 1 .1 2 6 2 .6 4 63.76 8 0 .8 0 ) 8 1 .9 6 ) 8 4 .0 0 ) 8 5 .5 0 ) 12557 12142 13323 14009 7 6 7 .1 -7 4 .6 (90-100) Long J . I . Case Long John D eere 1100 970 R 9500 4230 6 8 .6 0 6 9 .6 6 72.85 74.81 9 2 .0 0 ) 9 3 .4 1 ) 9 7 .7 0 ) 1 0 0 .3 2 ) 11239 14183 12888 15309 8 7 4 .6 -8 2 .0 (100-110) MF J . I . Case IH Deutz MF-1105 1070 966 D 10006 75.11 75.11 75.17 78.33 10 0 .7 2 ) 100.73) 10 0 .8 0 ) 105.04) 16266 15288 18084 16183 157 T able A.4B (co n tin u ed ) 9 8 2 .0 -8 9 .5 (110-120) White A llis-C h aim ers Ford MF 2-105 7000 G2615 M MF-1135 78.75 79.37 82.54 90.11 (105.61) (106.44) (110.69) (120.84) 15863 18533 15166 17642 10 8 9 .5 -9 6 .9 (120-130) J . I . Case IH Deutz John Deere 1175 1066 D 13006 4430 92.32 93.72 93.79 93.87 (123.80) (125.68) (125.77) (125.88) 17127 21081 19406 17755 11 96.9 -1 0 4 .4 (130-140) J . I . Case Ford A11 is-C halm ers 1270 H 2615M 7040 100.96 (135.39) 101.01 (135.46) 101.78 (136.49) 23638 17340 22054 12 104.4-111.9 (140-150) MF IH White John Deere MF-1155 1466 2-150 4630 105.12 108.70 109.98 112.35 20553 23640 21240 21736 *Massey-Ferguson **I n te r n a tio n a l H a rv este r (140.97) (145.77) (147.49 (150.66) 158 Table A.4C Carbine P rice Data. John Deere A llis-C h alm ers/ G leaner I n te r n a tio n a l H a rv ester M assey-Ferguson 2-RCW 4-ROW 6-RCW Model 3300 SP 4400 SP 6600 SP P r ic e ($ ) 16655 20839 25624 Model KKS FKS MKS P r ic e ($) 15244 19564 26037 715 SP 815 SP 21763 30853 915 SP C oraSoybean 36068 Model 8-ROW 7700 SP C om Grain-Soybean 31888 IKS CornSoybean 32420 P r ic e ($ ) --- Model P r ic e ($) 300 SP 14349 510 SP 20403 750 SP 25092 760 SP 32037 15416 20642 26902 33103 Average p r ic e ($ ) T able A.4D Oom Head P r ic e D ata. Make 2-RCW S ize 4-ROW 6-ROW -P ric e ($)- 8-RCW John Deere 2994 6574 8890 11552 A llis-C h a lm e rs/ G leaner 3135 6673 8959 11668 I n te r n a tio n a l H a rv este r 3340 7025 9440 12270 M assey-Ferguscn 3039 6774 8763 11523 Average p r ic e 3127 6762 9013 11753 159 Table A.4E Grain Head P r ic e Data. S ize Make 3.05 m ( 1 0 - f t) 3.96 m ( 1 3 - f t) 4 .8 8 m ( 1 6 - f t ) ------------------- P r ic e ( $ ) --------- ---------------------- - A llis-C h a lm e rs/ G leaner 2952 3192 (3212)* 3452 *For 3.96 m g ra in head a tta c h e d t o 6-row coabine T ab le A.4F P r ic e D ata f o r Pick-Up Head and A ttachm ents f o r F ie ld Beans. Size 2-ROW 4-ROff 6-ROW ------------------------P r ic e ($ )................... A llis -C h a lm e rs/ G leaner 2169 2266 3349 8-B0ff — ------------3324 160 Table A.5 Assumed Machinery Cost F a cto rs. M achinery c o s t f a c t o r Assumed v a lu e , and method o f c a lc u la tio n D e p re c ia tio n S t r a ig h t l i n e method assum ing a 10 p e rc e n t s a lv a g e v a lu e , maximum u s e f u l l i f e = 8 y e ars In te re s t 9 p e rc e n t annual i n t e r e s t on a v erag e in v estm en t Annual h o u sin g 0 .7 5 p e rc e n t o f i n i t i a l p r i c e Annual in s u ra n c e 0 .2 5 p e rc e n t o f i n i t i a l p r i c e Tax 0 .0 , no ta x on f i e l d m achinery in M ichigan R ep air A f ix e d p e rc e n ta g e o f t h e p u rc h a se p r ic e o v e r t h e w e ar-o u t l i f e o f a m achine, p r o r a te d a c c o rd in g t o an n u al m achine u se Labor $ 3 .2 5 p e r h o u r D ie s e l f u e l 1 0 .1 7 £ / l i t r e ( 3 8 .5 £ /g a llo n ) O il and f i l t e r 15 p e rc e n t o f t o t a l f u e l c o s t APPENDIX B THE PROCEDURE FOR CALCULATING MEDIAN COMPLETION DATE ICR PLANTING AND HARVESTING OPERATIONS APPENDIX B THE PROCEDURE FOR CALCTJALTING MEDIAN OCMPLETICN DATE FOR PLANTING AND HARVESTING OPERATIONS The m edian c a i p l e t i o n d a te f o r a p l a n t i n g o r h a r v e s tin g o p e r a tio n i s d e fin e d a s fo llo w s : t e d ia n c c n p le tio n d a t e where N h e c ta r e - d a y s = h e c t a r e p la n te d ( o r h a r v e s te d ) on day i x c a le n d a r d ay s e la p s e d from t h e s t a r t i n g d a te c o n s t r a i n t t o day i i = 1 on t h e s t a r t i n g d a te c o n s t r a i n t , and = N on a c t u a l c o n p le tio n d a te The w eekly o p e r a tio n s sc h e d u le p ro v id e s t o t a l a r e a p la n te d ( o r h a r v e s te d ) o f a c ro p in a week. Tb c a l c u l a t e d a i l y p l a n t i n g ( o r h a r v e s t i n g ) r a t e , t h e f r a c t i o n o f t h e week d u rin g w hich t h e o p e r a tio n was p erfo rm ed n e ed s t o b e d e te rm in e d . The f r a c t i o n o f t h e week ( s l .O ) d u rin g w hich p l a n t i n g r a t e o f a c ro p was assum ed t o b e u n ifo rm was t h e n a x in u n o f t h e f o llo w in g f o u r fra c tio n s : 1. The f r a c t i o n o f t h e week f o r w hich t o t a l u t i l i t y t r a c t o r tim e was u se d f o r p l a n t i n g t h e c ro p I f t h e c u m u la tiv e a r e a f i n i s h e d o f t h e p l a n t i n g o p e r a tio n i s e q u a l t o t h e e m u l a t i v e a r e a f i n i s h e d o f any 161 162 preplant t i l l a g e operation o f th e crop, 2. The f r a c tio n o f th e week f o r which t o t a l t i l l a g e t r a c t o r tim e was used f o r p re p la n t t i l l a g e o p e ra tio n s o f th e crop, 3. The b ig g e s t f r a c tio n o f th e week f o r which t o t a l a v a ila b le tim e o f any implement was used f o r a p re p la n t t i l l a g e o p e ra tio n o f th e cro p , I f p la n tin g o f th e crop im m ediately fo llo w s th e h a rv e s tin g o f a p rev io u s c ro p , and th e cum ulative a re a p la n te d i s eq u al t o th e e m u la tiv e a re a h a rv e ste d o f th e p rec ed in g crop, 4. The f r a c tio n o f th e week f o r which t o t a l h a rv e s tin g c a p a c ity was used f o r h a rv e s tin g p reced in g c ro p . Ih e f r a c tio n o f th e week (< 1 .0 ) d u rin g which h a rv e s tin g r a t e o f a crop was assumed t o b e unifoim was th e f r a c t io n o f th e week f o r which t o t a l h a rv e s tin g c a p a c ity was used f o r h a rv e s tin g th e crop. I t was a ls o assumed t h a t th e l a t t e r p a r t o f th e week i s used f o r p la n tin g ( o r h a rv e s tin g ) . However, i f th e o p e ra tio n was com pleted d u rin g a week, i t was assumed t h a t th e f i r s t p a r t o f th e week i s used f o r p la n tin g (o r h a rv e s tin g ). Sunday was assumed t o be th e f i r s t day o f a week and no work was perform ed on Sunday. I h e d a ily p la n tin g (o r h a rv e s tin g ) r a t e (ACEEPD) was c a lc u la te d by d iv id in g th e t o t a l a r e a p la n te d ( o r h a rv e ste d ) in th e week by 6 tim es th e f r a c tio n o f th e week used f o r p la n tin g ( o r h a r v e s tin g ) . The h e c ta re -d a y s o f d e la y f o r th e a re a p la n te d ( o r h a rv e ste d ) d u rin g a week were c a lc u la te d u sin g t h e fo llo w in g e q u atio n : M h e c ta re -d a y s d e la y = (7 * (I-L ) + J ) ACHEP 163 where K = 2, when f i r s t p a rt o f th e week i s used, and = 7, when l a t t e r p a r t o f th e week i s used M = 6 * f r a c tio n o f th e week used f o r p la n tin g (o r h a rv e s tin g ) j + 1, when f i r s t p a rt o f th e week i s used = 7 - [6 * f r a c tio n o f th e week used f o r p la n tin g (o r h a r v e s t i n g ) ] 3 when l a t t e r p a r t o f th e week i s used I = sequence nuriber o f th e week L = sequence number o f th e s ta rtin g d a te weekc o n s tr a in t ACHEP = Minm (ACREPD, ACREL) ACHEL = T b ta l a re a t o be p la n te d ( o r h a rv e ste d ) d u rin g th e week - th e a re a p la n te d ( o r h a rv e ste d ) b e fo re day J . APPENDIX C FIELD MACHINERY REQUIREMENTS FOR THE SELECTED MICHIGAN CASH CRCP PRODUCTION SYSTEMS *3•* b wi be s 40.3 sttf* b ft ft ft eo r3 co fli f t w o cq o> f t to I a a sis 5 83 a s ssss * Li -4 ao £ b u u a g b# ftto b ♦ £888 ft A^ b a n- ft b u b ft c o SP contiine1 (no. of rows)** T il la g e t r a c t o r (PTOkW) U t i l i t y tractor (PTOkW) Machinery 53.7 sas* qc gi F arn s i z e (b a) Field ca to ~ — 3 2Sa UUOU C. I 8 o> f t to to — ■«* S2S3 U'OOU Tuhlc 124.2 to —— * 2 S 3} 522 c bu 3 co4oeo 2.9 ftb b CJft 0>ft to tofed Holdboard plow ( do. o f 0.41 m bottonw) ftCJ'ON C J M 6 3 60 D isc-taaraow (m) co y» w b b* b b b (n ) the G rain d r i l l Selected (m) oda 09 01 f t f t Hawer-cooditiooer1 ( do. of u n its) COCBft ft P la n te r* (no. of rows) N o - till p la n te r (n o . o f row s) OBO) 00 ft 01 4J>ft 40 «3 C to Wto to 5tr *-mnw Amrooia. ap p licato r (no. o f rows) M tfl ft (J SI £ 40CJ to CO n bbbb -i B aler* (no. of u n its) H otary c u t t e r (m) F e r t i l i z e r spreader* (do. o f units) S p ra y e r' ( do. o f u n its) F ie ld bean p u l l e r (n o . o f row s) m SystcjiB, H S H M Cash Cnif> Pm dut’tlim 00C) ft ft Michigan Hcw-cultivator (no. o f rows) ft ft for Q iis e l plow N N M ta ft b go to terpjl n n c n ts A lf a l f a t r a c t o r 1 (n o . o f u n i t s ) 112.5 173.2 214.1 248.9 30 ** y ^ S2 ^ tO *0 ^ to I* f e n A h ) G9 c (ba) 30 O •£• t o CO w 39 OJ A *o CO SP ocnto i n e : 2 4 0 8 (DO. O f KKfS)*“ g oo b oo bo 3j 3 S 3 S g 22.4 22.4 30.8 40.3 P^KES Ua ^ b b b § 888 8 g g oa oo bo 03 g T illa g e tr a c to r (PTCkT) U tility tr a c to r (PTCkW) £852 f3 b b b b A lfa lfa tr a c to r 1 (n o . o f m i t s ) 9) wiu to to M eo 2.0 2.0 2.0 2,4 b b o b 1.2 1.2 1.2 1.8 Oft to M to U oldboard plow ( do . o f 0 .4 1 m b o tto m s) cji cj to b b b b fc9 U to to D lsc-b arro w (m) boob C h is e l plow (m) G ra in d r i l l Cm) Row-cultivator ( do. of rows) Nower-conditloner3 ( do. o f u n its) fefe A * P la n te r ' ( do . o f row s) 09 O rffc Ok 4 4 6 8 K M 4 4 8 8 N o -till p la n te r ( d o . o f ro w s ) S U1^ CJ U ^ A m n ia , a p p l i c a t o r ( d o . o f row s) mAUU 3 3 4 5 B a ler* (n o . o f u n i t s ) k pHm 2 .1 2 .1 2 .7 3 .7 to to to to o o 'mp* R o tary c u t t e r t* S F e r t i l i s e r s p re a d e r* (n o . o f u n i t s ) f5 3 -I 3 3M "I £ S p ra y e r7 (n o . o f u n i t s ) F i e l d bean p u l l e r (n o . o f row s) S9I ( c o n tin u e d ) 29.8 29.8 33.0 44.7 5 C. 1 n GO Farm s i s tO b b U Dible C O tO M wik —' -vj — ' CON M - c —a b 00 A wb M $ 9 S £ K f3 QDA A — sc * M ^ 2b yj OU 0 5 a Si n OP C* A CO a a a a ^*j - 0 0 o» ^ CO— C? C5 in 4U M S §j 3 £ b b !a as 5 1M /S 2 b b Ok b as 3) j . ts 0 3 OB O Ok CO S> c o n b in e 1 (n o . o f ro w s )” b b b 00 5 i1 ■ M 9 3*288 od w to b • # T illa g e t r a c t o r (FTGkW) A Ol A to ® & C CO A to U 8 * * 8 b b u a rare) s i z e (ha) p u to So U tility tra c to r (PTCfcW) 3 3 8 S ^ M M ffl A lf a lf a t r a c t o r 1 ( 00 . o f m i t s ) W 9 * p iu o iu u to o b t (J 01 A W © tf» A w M W CJ CO b» b in © ci cn cj co b to b 0 01 A a * t * M ol& aard plow (d o . o f 0.41 m b o tta s s ) a u o im D isc-harrcw u b tto b (a) C h ise l plcw A U bJ — U^)ib« (m) G rain d r i l l (») as a B o w -cu ltlv atar ( do. o f towb) go m M ow er-condlticner1 (d o . o f u n it s ) P la n te r* (no. o f row■) Q (8AO0) N o - till p la n te r (d o . o f rows) 3 h a s 00 - j * — B a le r1 (d o . o f u n it s ) 5 H £ Rotary c u t t e r (m) F e r t i l i z e r spreader* (no. o f u n it s ) 5«• 3 --------a a a a Aonsola a p p lic a to r (d o . o f rows) 1>— ■ 1 — ■ ^ 1 — 1»— QDCJ ^ A 991 1—* — • S p ra y e r7 (no. o f u n it s ) F ie ld bean p u ll e r (no. o f rows) (c in tln u e d ) 3 u t« « w b b * * n n CQ * Dilile (11 ■i* 3U M -v} VI w -a b n n 5 * s a b y» 5 50.7 3 8 Is as cj a eo 3& 8S to b 5 ©^ 9 © Q Oa W •JvJM w MM Q 3 * 1 H 3 9 ■^y M - n b —b b ob © a ro n CQ * i H H ts ^ a b b b * © ^ to S S S S j! b ©b b 9 S& SS b b b Jk u to b O C M * F a ia s i z e (ba) SP ao c b ln e ' (no. o f rows)** T illa g e t r a c t o r (PTOfcW) U t i l i t y trm c to r (PTCkW) A lf a lf a t r a c t o r 4 (n o . o f u n its ) fl cn ^ • * ifr «0 5.2 Li K> b o cj bn to b 3.7 M J-* 4.0 UM a a co to o b b i ^ 00 C5 <9 A 8 © oi * to Ifcldbaard plcm (n o , o f 0.41 m b a tta n a ) CJ U TOto bi bi * b tn J* w to to b b b Msc-banr>w MM n m OOMw Q iis e l plow ^ COto o o b Ob G rain d r i l l o b b ^ 05 © Jb Ob ftc w -c u ltiv a to r (no. o f rows) ^ jh OQ a (m) (n) (m) Ito w rn x o n d itio o e r3 (no. o f u n its ) QB© Ufc Jk 8 OB© CD»» 00 © Ob Ub 3 M b - tlll p la n te r (no. o f rows) o 7 30 OBCHW — P la n t e r 1 (n o . o f rows) Armenia a p p lic a to r (n o . o f raws) CP 01 CJ CO P B a le r5 (n o . o f u n its ) <3 H 3 .7 u u to 1C ft cj to to 1) ’-J >- Hotary c u t t e r (m) F e r t i l i z e r s p re a d e r1 (no. o f u n its ) d 00 31 A A — 3 ---------- =? ------ S p ra y e r7 (n o . o f u n it s ) Field bean p u ll e r (n o . o f tows) 00 O ft ft L91 (co n tin u ed ) 101.4 A W C-3 CO«— yi 35 -j m CUKCC n b c iib i n Tnltle C.1 3 3b yi a S 2 H Wb — to A- Jk ^ m a'PfSS c ©b b •j b O « ao a a w N 5 >• 82 fllU I^ M to K? ►- © b* u b* b b b b 09 £H s s O ifr b b 2 8 b b 58 88 32 i £ * s 3 b b b b Fans s iz e (h a ) SP c a rb in e 1 (no. o f rows)** T i l l a ge t r a c t o r (PTOcW) (c u n tIn u e d ) 3 8 tO A « to — 3S C.l * u CO %$ b b Table Sj§ b b U tility tr a c to r (PIOcW) A lf a lf a t r a c t o r 1 (n o . o f i n l t s ) U o ld m ard plow (n o . o f 0 .4 1 m b o tta o a ) Ulu wb to to CO |U u ifc u to to bo b b b b b b bb b © m N N u b b U 'J u u b o o b Dlac-fcarrar (m) C h ise l plow (m) w h b b b b 4A U M b b G rain d r i l l > 3 s b 8 b * bs cj u 5 cn j g s b n b to X ® rt M La * a* t o > a 5 8 b ^ ■U N CO 5 s M a Z Ok CO ?* H b b 8 2 b b U b 00 a > > n b b 0Q 03 m Fatrc s i z e (h a ) Xk M r « s* n Xk t o * Xk t o 3> > is a 3 La b 3 a Z b b b Xk > > in os 3 kwt a z m S 3 c n t— SP c c o b in e 1 (n o . o f rows)** T illa g e tr a c to r (PTCkk) (J tility tr a c to r s (FTOcW) c n co A lfa lfa tr a c to r 1 (n o . o f u n i t s ) to to A CO Moldboard plow cn u to to u b b c n '* to to ^ to O Xk tO IO U CO b. b cn o (n o . o f 0 .4 1 m b e t t e r s ) cn b to Dlsc-barrow (m) t o H- h * w- to > - C h is e l plow OD t o b Q0 tO Xk b (m) C J CJ ib u o u u u A CJ b o o b b o o Lj G ra in d r i l l Hw* b OD b 00 Xk .Xk J k CJ cn u ttk J k 00 * * *2 cn cj r* Si H u (m) 0 3 Xk f tjw - c u ltiv a to r (n o . o f row s) C l Xk ca x t U o w e r-ctn d it i o c e r 1 (n o . o f u n i t s ) Ob «k CB Xk P l a n t e r 1* (n o . o f rcwa) N o - till p la n te r (n o . o f rows) W dj M £* 7>A. J in A enxsla a p p li c a to r (n o . o f row s) ■ 0) £> i -i H EJ MM ~ MM C B a le r5 (n o . o f u n i t s ) to ta ry c u tte r (m) £ “ 3 F e r t i l i z e r sp re a d e r* (n o . o f u n i t s ) §NH j S p ra y e r7 (n o . o f u n i t s ) F i e l d bean p u l l e r (n o . o f rtw s) 691 T ab le C .l (c o n tin u e d ) u u o I K t( tn go si AB & H V 238.4 4 0 8 .3 C H) » A A HOTATICN 2 4 C C Hi * 2 4 a a 3 6 .5 6 2 .6 2 4 .6 4 2 .5 2 4 4 6 2 .9 5 .2 3 .0 4 .0 4 8 3 5 2 4 2 9 .8 4 1 .8 2 2 .4 2 8 .3 k l 4 8 H is i 3 ° 3 5 ■wd 3 5 2 4 2 .0 3 .5 1 .8 2 .4 3 .0 4 .0 4 4 3 5 4 4 3 5 3 5 1 .5 2 .7 3 ■H § b, U m 3 t? s i i f ** ° t) n s i £ 5 im m s m 1 1 3 5 U lfbtK LEVEL OF TlflAGE <: c m w A A BOTATirW 2 38 .4 4 0 8 .3 a° ID C 0 "u ° & 8 S3 h i g h e s t l e v f j , o f tiujvce rcnw ncN 2 2 .4 3 7 .3 o. u H Vl & H 1 1 4 4 isiwsm 1 1 1 1 4 4 LOWEST LEVEL OF TIUACE lw m e iT Y 2 5 2 3 2 .0 2 .4 1 .2 1 .8 3 .0 3 .7 4 4 3 5 4 4 4 4 3 4 3 5 1 .5 2 .1 l l l i 4 4 *T\vo u n i t s o r t h i s sis® w ere r e q u ir e d ♦♦A 76 cm row w id th was assu n e d F i e ld im c h ln ery r e q u lr a n u n ts w ere c a l c u l a t e d u s in g t h e c u ip u t e r model d e s c r ib e d In C h a p te r 3 nnd In p u t d a ta o f Appendix A. D esign p i t b a b l l l t y was rix e d a t 80 p e r c e n t. S u f f i c i e n t n d d i t l o i a l la b o r a n d rm ch ln ery wns assumed t o b e a v a i l a b l e t o tr a n s p o r t h a r v e s te d c ro p to llie fn rn s te u d . T h e re fo re , no t i l l a g e t r a c t o r was k e p t i d l e wbcn a h a r v e s t e r wns o p e r a tin g in t h e f i e l d . ■Necessary a ttn c tm e n ts - a c o m h e ad o f c o rre sp o n d in g B iz e , i f a c ro p r o t a t i o n in v o lv e d o n m , a g r a in head (3 m f o r 2-row contolne, 4 m f o r 4 o r 6 -ro w c o rtiin e , and 4 .0 m f o r 8-row c a r b i n e ) , i f a c r c p r o t a t i o n in v o lv e d so y b ean s o r w h e at, and a p ic k - u p head o f c o rre s p o n d in g s i z e , I f a c ro p r o t a t i o n in v o lv e d f i e l d b e an s, t r a c t o r wns o f 2 9 .8 PTOkl s l a e . ’ Each n riw e r-c c n d lt lo n e r was 2 .7 5 m w ide (Jo h n t o r r e 1209 m w e r-c o n d i t i m e r ) . 'P la n te r wlLh d ry f e r t i l i z e r and h e r b ic id e a t t a r J r i m t s whs asmired. s,lohn D eere 336 w ire b o J c r w ith p ick -rg r. ’ .M m t o * r e 602 s p in s p r e a d e r ( 1 ,7 3 in* c a p a c ity ) '.John Itoere 220 t r a c t o r m ounted s p r a y e r w ith 6 m b e l l y m xm tod brunt. 170 2:58.4 4 0 8 .3 5 6 .7 9 6 .2 p LIST OF REFERENCES LIST OF REFERENCES Adams, W. 1975. P e rso n a l c a n ru n ic a tio n . Crop and S o il S c i. D e p t., M ichigan S ta te U n iv e rs ity , E ast L ansing, MI. ASAE D230.1. 1969. Farm m achinery c o s ts and u se . A g ric u ltu ra l E n g in eers Yearbook. ASAE, S t. Joseph, MI, p 278-283. ASAE D230.2. 1977. A g ric u ltu ra l m achinery management d a ta . A g r ic u ltu ra l E ngineers Yearbook. ASAE, S t. Jo se p h , MI, p 326-333. Ayres, G. E. 1975. A sim u la tio n f o r p r e d ic tin g days s u ita b le f o r c o m h a rv e s tin g . ASAE Paper No. 75-1502. ASAE, S t. Joseph, MI. Ayres, G. E. 1976. Fuel req u ire m e n ts f o r f i e l d o p e ra tio n s . Coop. E x t. S e rv ic e , Iowa S ta te U n iv e rs ity , Ames, IA. B a ie r, W. and G. R obertson. 1966. A new v e r s a t i l e b u d g et. Can. J . P la n t S c i. 46:299-315. s o i l m o istu re B olton, B i l l , J . B. Penn, F. T. Cooke, J r . , and A. M. H eagler. 1968. Days s u i t a b l e f o r f i e l d work - M is s is s ip p i R iv er D e lta o o tto n a re a . D ept. Agr. E con.R es. Rep. No. 384. D ept. Agr. Econ. & A g rib u sin e ss, L o u isia n a S ta te U n iv e rs ity , Baton Rouge, LA. Bowers, W endell. 1970. Modern co n cep ts o f farm m achinery management. S tip e s P u b lish in g C o., Chanpaign, IL. Bowers, W. 1975. S e le c tio n o f m achinery f o r a 50,000 h e c ta re farm ing o p e ra tio n in Y ugoslavia. ASAE P ap er No. 75-1006. ASAE, S t. Joseph, MI. Burrows, W. C. and J . C. Siemens. 1974. D eterm ination o f cptim un m achinery f o r com -soybean farm s. T ra n sa c tio n o f th e ASAE 17(6):1130-1135. C a rp en ter, M. L. and D. B. Brooker. 1970. Minimum c o s t m achinery system s f o r h a rv e s tin g , d ry in g and s t o r i n g s h e lle d c o m . ASAE P ap er No. 70-322. ASAE, S t. Joseph, MI. Census o f A g ric u ltu re . 1969. Volume 1, p a r t 13, s e c tio n 1. Government P r in tin g O ffic e , W ashington, DC. 171 U. S. 172 Oonm ittee on A g r ic u ltu r a l P ro d u ctio n E ffic ie n c y . 1975. A g r ic u ltu r a l P ro d u c tio n E ffic ie n c y . N a tio n a l Academy o f S c ie n c e s, W ashington, DC. Connor, L. J . 1976. P e rso n a l com nunication. D ept. Agr. E con., M ichigan S ta te U n iv e rs ity , E a st L ansing, MI. D eere and Conpany. 1975. A g r ic u ltu r a l Whole Goods P r ic e L i s t . R ev isio n 6. M oline, IL. E id sv ig , D. H. and C. E. O lson. 1969. D eterm ining l e a s t - c o s t m achinery c a ib in a tio n s . B u ll. 479. D ept. Agr. E con., Agr. Exp. 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B. H oltm an. 1974. M achinery complement s e l e c t i o n b a se d on tim e c o n s t r a i n t s . ASAE P a p e r No. 74-1541. ASAE, S t . Jo se p h , MI. Iirplem ent & T r a c to r , Red Book. Kansas C ity , MD. 1977. I n t e r t e c P u b lis h in g C o rp ., K ish , A. J . and C. V. P r i v e t t e . 1974. Number o f fie ld w o rk in g days a v a i la b l e f o r t i l l a g e in S outh C a ro lin a . ASAE P a p e r No. 74-1019. ASAE, S t. Jo sep h , MI. lin k , D. A. 1962. W eather p r o b a b i l i t i e s a f f e c t i n g m achine sy stem c a p a b i l i t i e s . U npublished Ph.D . d i s s e r t a t i o n . L ib ra ry , Iowa S t a t e U n iv e rs ity , Ames, IA. L ink, D. A. 1968. R esearch needs f o r farm m achinery s c h e d u lin g . C brrputers and farm m achinery management p ro c e e d in g s . ASAE P u b lic a tio n PR0C-468:28-32, S t . Jo se p h , MI. L ink, D. A. and C. W. Bockhop. 1964. M athem atical approach t o farm m achine s c h e d u lin g . 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