Office File 1971 Research Report MONTCALM EXPERIMENTAL FARM Michigan State University Agricultural Experiment Station ACKNOWLEDGEMENTS Research personnel working at the Montcalm Experimental Farm have received much assistance in various ways. A special thanks is made to each of these individuals, private com­ panies and government agencies who have made this research possible. Many valuable contributions in the way of fertilizers, chemicals, seeds, equipment, technical assistance and personal services as well as monetary grants were received and are here­ by gratefully acknowledged. Special recognition is given to Mr. Theron Comden for his devoted cooperation and assistance in many of the day-to-day operations and personal services. TABLE OF CONTENTS INTRODUCTION 1 WEATHER FIGURE 2 Page A. POTATO STUDIES Soil Fertility Research with Potatoes M. L. Vitosh 4 Effect of Harvest Date and Storage on the Yield Potential of Onaway and Sebago Seed Potatoes R. W. Chase 18 Plant Spacing Studies R. W. Chase and N. R. Thompson 21 Potato Vine Killing Results in 1971 R. W. Chase, W. F. Meggitt and R. C. Bond 23 Potato Breeding N. R. Thompson 26 1971 Overstate Potato Variety Trials R. W. Chase and N. R. Thompson 30 Water Management of Potatoes R. J. Kunze and A. Garay 37 Influence of Water, Systemic Insecticides and Sidedress Nitrogen on the Incidence of Speckle Leaf M. L. Vitosh, R. W. Chase and A. L. Wells 42 Herbicides for Weed Control in Potatoes D. Wyse, W. F. Meggitt and R. C. Bond 46 Insecticide Evaluation A. L. Wells 48 Green Manure Study H. L. Kohls and R. W. Chase 58 B. OTHER CASH CROPS Corn Hybrids, Plant Population and Irrigation E. C. Rossman 60 Yield Data and Summary Statement from the Miscellaneous Colored Bean Test M. W. Adams, A. W. Saettler and Jerry Taylor 68 Lupine Research H. L. Kohls 70 Soil Fertility Research on Dent Corn, Sweet Corn, Soybeans and Red Kidney Beans M. L. Vitosh 74 Preplant Incorporated and Preemergence Herbicide Combinations for Weed Control in Navy Beans D. Wyse, W. F. Meggitt and R. C. Bond 86 MONTCALM BRANCH EXPERIMENT STATION RESEARCH REPORT R. W. Chase, Coordinator Department of Crop and Soil Sciences INTRODUCTION The Montcalm Experiment Station was established in 1966 with the first experiments initiated in 1967. This report marks the com­ pletion of five years of studies. The 80 acre facility is leased from Mr. Theron Comden and is located one mile west of Entrican, Michi­ gan. The farm was established primarily for research on potatoes and is located in the heart of a major potato producing area. Crops commonly used in a potato rotation are also being investigated. This report is designed to coordinate all of the research data obtained at the facility during 1971. Much of the data herein represents ongoing projects so complete results and interpretations may not be final. Results presented here should be treated as a progress report only as data from repeated trials are necessary before definite conclu­ sions and recommendations can be made. Weather Temperature and rainfall recordings are shown in Figure 1. An exceptionally warm and dry spring allowed for early plot plantings with­ out any interruptions. This weather pattern continued through June and the plots required supplemental irrigation early in the growing season. The graph reveals an unseasonable warm period during June with tempera­ tures in the 90's three times during the last week. Rainfall was unseasonably low throughout the entire growing season. If one considers May through August as the peak growing season, total rainfall during this period was 6.32 inches. This compares with 18.92 inches during the same period in 1970 and 14.25 inches in 1969. As a consequence irrigation was greatly increased. Most of the potato research plots (unless otherwise specified) received supplemental irrigation of 12-13 inches. Irrigation was initiated on June 11 and the final application was on August 17. The supplemental irrigation requirements for the 1971 crop were nearly double that of 1970. Empty Table Cell AVERAGE MONTHLY TEMP. RAINFALL APRIL MAX. 53 MIN. 31 1.59 inches MAY MAX. 65 MIN. 39 .93 inches JUNE MAX. 81 MIN. 56 1.50 inches AUGUST MAX. 80 MIN. 53 JULY MAX. 82 MIN. 55 1.22 inches 2.67 inches 4.00 inches SEPT. MAX. 73 MIN. 54 Fig. 1. CLIMATOLOGY OBSERVATIONS MADE AT THE MONTCALM EXPERIMENTAL FARM IN 1971 Soil Tests Soil test results for the general plot area are as follows. For specific projects where more detailed analysis are needed, the results are reported with the individual reports. pH 6.6 Pounds/Acre P 189 Disease and Insect Control Pounds/Acre K 216 Pounds/Acre Ca 743 Pounds/Acre Mg 149 A systemic insecticide was applied to most of the potato plots at the time of planting. The foliar insecticide program began on June 12. The foliar aphid control program was initiated on June 19 and continued on a seven day schedule throughout the growing season. Aphid control was very satisfactory. The fungicide spray program was initiated on June 26. All spray applications were made with an air blast sprayer. The insecticides used were Disulfoton, Phorate, Endosulfan, Carbaryl, Dimethoate and Meta-Systox-R. The fungicide used was Dithane M-45. Linuron (Lorox) at 1 3/4 lb/A and applied pre-emergence (approximately 15 days after planting) was used as the herbicide. SOIL FERTILITY RESEARCH WITH POTATOES M. L. Vitosh Department of Crop and Soil Sciences Five soil fertility experiments were conducted on potatoes in 1971. All except the fertilizer materials experiment were established in 1967. Slight modifications of the experiments, however, have been incorporated from year to year. The major crop sequence in the past has been potatoes followed by red kidney beans and then sweet corn. In 1971, potatoes followed either dent corn, sweet corn or red clover. Irrigation was initiated June 16 and continued until August 13. Because of the unusually dry season, approximately 9.4 inches of water was applied in 11 applications. Soil tests and other management practices are given at the bottom of Tables 1, 4, 6, 8 and 10. The soil on which these experiments were established has been classi­ fied as McBride sandy loam. A more detailed examination of specific areas indicates that there are local areas which are not typical of the major soil type. Montcalm sandy loam is present in small scattered areas of the major soil type. The main difference between these two soil types is the presence or absence of a fine textured "B" horizon. The McBride soil contains a thicker, fine textured "B" horizon than the Montcalm series. The manage­ ment of these two soil types may be quite different with regard to irrigation and nitrogen losses through leaching. Since these small areas cannot be managed separately, either on a small experimental scale or in a large field, no attempt has been made to make any adjustments for this variability in soil type. The variability in soil type does account for some of the variability in yields. Source, Rate and Time of Nitrogen Application: The design of this experiment was the same as in 1970. A slow release form of nitrogen (sulfur-coated urea) was incorporated to evaluate its per­ formance as a source of nitrogen. Total yield of Russet Burbank potatoes in this experiment in 1971 was slightly lower than in 1970, as was also true of the other experiments in 1971 (Table 1). Reasons for the lower yields are not apparent. Total yields of the Sebago variety were very comparable to 1970. Size in 1971 was far superior for both varieties. Approximately 95% of all the tubers were market­ able (larger than 1 7/8" diameter). Nearly 30% of the Russet Burbanks were over 10 ounces. Nitrogen beyond the first increment (120 lb total N/A) had no effect on size. Differences between broadcast and sidedress applications were not as apparent in 1971 as in previous years. Broadcast applications of N in previous years have been inferior because of leaching losses. This past season was very dry and no appreciable leaching occurred. A total of 180 lb N/A, either broadcast or sidedressed, produced maximum yields. Specific gravity of Russet Burbank tubers was not affected by rates of nitrogen. Sebago tubers from the check plot had lower specific gravity than all N treatments. This has not been observed before. Chip color rating which was only determined on the Russet Burbank variety was not significantly affected by N treatments. Ratings were made on the basis of the 1-10 reference standard prepared by the Potato Chip Institute Inter­ national. All chips were of acceptable quality. Potato petiole analysis is shown in Table 2. These samples were taken approximately two weeks earlier than last year. Nitrogen content in general was slightly higher than in 1970. Based on two years data, potato petioles should contain about 2.3 to 2.7% N at 45 to 60 days after plant emergence. Phosphorus, calcium, iron, zinc, and boron were not significantly affected by N treatments in 1971. In 1970, these elements were significantly affected. Manganese was the only element besides N affected both years. Higher rates of N resulted in higher manganese levels in potato petioles. Increased acidity caused by higher N rates may account for the increased manganese uptake. The potassium content was slightly higher where no N was applied, a trend also observed in 1970. Soil samples were taken from each plot after harvest and analyzed for nitrate-nitrogen. Because the surface soil was very thoroughly mixed by the action of the potato digger, variation between the plots in any given treat­ ment was very small, resulting in highly significant differences due to treat­ ments and varieties. Soil nitrates were higher where larger rates of N were applied. The soil nitrate levels were also consistently lower where Russet Burbank potatoes were grown. This may indicate that this variety has a higher N requirement. The difference in nitrates in the surface 9" is equiva­ lent to about 12 lb N/A. This represents only a very small amount of the total used on potatoes. This total difference may be more significant than is observed for the top 6 inches. Other evidence to support the idea that the Russet Burbank has a higher N requirement than most other varieties is that the petioles will normally run 0.2 to 0.3% higher than that of the Sebago variety. Potassium-Magnesium Study: This experiment was established in 1967 to evaluate various rates of broadcast, banded and fall applied potassium. Four years of data indicate very little difference between methods of application. In 1971, the experi­ ment was changed to evaluate four rates of potassium with and without magnesium. Russet Burbank yields were better than the N rate experiment; however, there was a difference in the seed spacing. Russet Burbanks were planted in 10 inch seed spacing in this experiment, compared to a 14 inch spacing in the previous experiment. Yields were increased slightly with the first increment of potassium, but the increase was not large enough to be statistically significant. Specific gravity decreased with increasing rates of potassium, especially where magnesium was applied. The additional salt under dry soil conditions may account for the reduced specific gravity. Size and chip color were not affected by the potassium or magnesium treatments. Petiole analysis (Table 5) indicated that Ca, Mg, Al and Ba were the only elements significantly affected by the potassium and magnesium treat­ ments. Potassium fertilizers decreased the Ca and Mg content of petioles. No explanation can be offered for the observed Al and Ba differences. In 1970, K, Ca, Mg, and Fe were the only elements significantly affected by the K treatments. Potassium Carrier Study: This experiment was begun in 1967. This spring it was discovered that potassium-magnesium sulfate was used in place of potassium sulfate for (1969 and 1970). The data reported for the K sulfate treatment for these two years should be ignored because the rate of potassium supplied was not equal to the other potassium sources. Total yields in 1971 were increased with potassium, especially for the Sebago variety (Table 6). Differences due to potassium sources were not statistically significant. All sources gave equal yield responses. The same trends were observed for the various size classes and chip color. All sources of potassium decreased specific gravity over the no-potassium treat­ ment. Petiole analysis (Table 7) indicates that K, Ca, Mg, Zn and Ba were significantly affected by the treatments. Potassium, regardless of source, increased potassium content and decreased the Ca and Mg content of the petioles. The highest Zn content and lowest Ba content was observed with the potassium sulfate treatment. Nitrogen Carrier Study: This study was started in 1967 to evaluate five sources of N on yield and quality of potatoes. In 1971, 20 lb N/A as ammonium nitrate was banded on all treatments to eliminate any early difference due to fertilizer placement. All N sources were topdressed just prior to emergence, except anhydrous ammonia which was knifed in at the same time. In 1970, it was felt that the anhydrous ammonia treatment was at a disadvantage early in the season because of fertilizer placement. Total yield for Russet Burbank was not affected by the five N carriers (Table 8). Urea, however, appeared to be superior to calcium nitrate and anhydrous ammonia treatments for the Sebago variety. Anhydrous ammonia also appeared to lower the specific gravity of the Sebago variety. Again, good size distribution for all sources was observed with approximately 95% and 92% of the Russet Burbank and Sebago potatoes, respectively, being marketable (greater than 1 7/8 inches in diameter). A four-year and five-year average for these N carriers is shown in Table 9. Urea and anhydrous ammonia appear to be superior for the Sebago variety. Calcium nitrate seems inferior as a N carrier for both varieties. All of the nitrogen in calcium nitrate is in the nitrate form, and is more subject to leaching in wet years than the other sources containing the ammonium form. Fertilizer Materials Study: In 1971, a new experiment compared liquid versus dry fertilizers and polyphosphate versus orthophosphate. Yields for this experiment were not quite as high as some others because the area was somewhat difficult to irrigate. Analysis of the overall experiment indicated that neither yield nor size were significantly affected by the treatments. The average of the three dry fertilizer treatments out-yielded the liquid fertilizer treatments by 9 cwt/A. Polyphosphate produced higher yields than orthophosphate, however, caution should be used in placing too much emphasis on one year of data. Many other experiments on other crops have indicated no clear-cut advantage to either source of phosphorus. Table 1. Effects of rate, source and time of nitrogen application on yield, size, chip color and specific gravity of irrigated Russet Burbank and Sebago potatoes. Nitrogen Application (a) Total lb N/A Russet Burbank Over Russet Burbank 10 oz - Total Russet Burbank Yield 10 oz % 1 7/8" % (cwt/A) Russet Burbank Less Than 1 7/8" % Russet BurbankOff Type% Russet Burbank Chip Rating Russet Burbank Sp. Gr. Sebago Total Yield (cwt/A) Over Sebago 3 1/4" % Sebago Sebag o 3 1/4" - 1 7/8" % Less Than 1 7/8"% Sp. Sebago Gr. 0 120 180 240 300 180 180 300 400 240 135 243 280 275 277 274 285 308 285 303 8 19 24 33 29 29 28 28 25 31 6 -- 73 62 57 51 52 54 48 51 51 49 6 7 9 6 5 3 4 4 4 4 6 6 3 3 5 5 4 4 5 5 5 5 5 4 NS -- 10 13 14 13 15 13 20 17 18 17 3 -- 1.075 1.076 1.077 1.076 1.076 1.076 1.078 1.078 1.075 1.075 .004 .003 173 377 433 412 438 424 416 419 397 421 45 48 4 5 9 12 9 10 10 11 12 11 6 -- 83 89 85 81 86 86 85 84 81 83 6 7 13 6 5 7 5 4 5 5 6 6 3 3 1.068 1.073 1.075 1.071 1.074 1.072 1.076 1.073 1.072 1.075 .004 .003 Nitrogen Application (a) Nitrogen Application (a) Broad­ Band­ cast lb N/A ed Nitrogen Application (a) Side­ dressed lb N/A lb N/A 0 0 60 SCU 60 U 120 U 180 U 240 U 60 U 60 U 60 U 0 0 0 0 0 120 SCU 60 U empty table cell 0 60 U 120 U 60 U 240 u 60 U 360 U 0 0 180 SCU 60 U 0 LSD (.05) treatments within varieties empty table cellempty table cellempty table cell45 LSD (.05) varieties within treatment empty table cellempty table cellempty table cell 48 (a) Broadcast urea (U) and sulfur coated urea (SCU) was applied and plowed down two days prior to planting. Banded urea was applied at planting time 2 inches to side and 2 inches below the seed piece. Sidedress urea was applied to soil surface on June 10 prior to hilling. Planted: April 23, 1971. Harvested: September 27, 1971. Harvest Area: 266 sq. ft. Row Spacing: 32 inches. Seed Spacing: Russet Burbank = 14", Sebago = 10" Basic Fertilizer: 0-150-200 banded at planting time. Irrigation: 9.4 inches Previous Crop: Field corn Soil Test: pH = 6.5. P = 275. K = 196 Table 2. Effect of rate, source and time of nitrogen application on the elemental composition of potato petioles. (Russet Burbank and Sebago varieties sampled 7-13-71) Treatment (a) Elements (b) Elements (b) Elements (b) No. N % Elements (b)P % Elements (b) K Elements (b) Ca % Mg % Fe ppm Elements (b)Zn Elements (b) Ba (b)Mn ppm Elements % 11.96 9.64 8.69 9.22 9.29 10.30 9.72 9.91 9.12 10.31 .33 .29 .32 .28 .30 .32 .29 .29 .32 .31 1.8 2.6 3.0 2.8 2.9 2.7 2.9 3.0 3.1 2.9 .66 .68 .62 .68 .70 .62 .66 .70 .68 .66 .33 .58 .63 .69 .63 .58 .63 .77 .70 .60 ppm ppm 23 28 34 33 35 28 28 34 33 29 90 54 46 60 57 46 53 55 49 54 36 84 83 97 161 61 63 80 97 75 54 57 56 58 39 38 41 48 41 39 .3 NS .9 NS .08 NS NS 14 19 1 2 3 4 5 6 7 8 9 10 LSD (.05) (a) Treatments are the same as in the previous table. (b) Other elements which were not significantly affected by the treatments in this experiment: Cu, B, Na and Al. Table 3. Nitrates remaining in the surface 9 inches of a McBride sandy loam soil at harvest time as affected by two potato varieties and ten nitrogen treatments (sampled 9-29-71) Nitrogen application Nitrogen Application Nitrogen Application Broad cast lb N/A Band ed lb N/A Side dressedlb N/A Total N ppm NO 3-N Varieties Varieties Russet Burbank ppm NO3-N Sebago ppm NO3-N 9 10 11 14 15 12 10 15 12 14 12 — Treatment 3-N Average ppm NO 9 12 13 19 19 11 12 18 20 16 — 4 — — — 9 14 15 25 22 11 14 22 27 18 18 — 5 5 0 60 SCU 120 U 180 U 240 U 60 SCU 0 0 0 120 SCU 0 0 60 U 60 U 60 U 60 U 60 U 60 U 60 U 60 U 0 0 0 0 0 0 120 U 240 U 360 U 0 0 60 180 240 300 120 180 300 400 180 Variety Averageempty table cell LSD (.05) Treatmentsempty table cell LSD (.05) Varietiesempty table cell empty table cellempty table cell empty table cellempty table cell empty table cellempty table cell empty table cell 2 LSD (.05) Treatments within Varietiesempty table cell empty table cellempty table cell LSD (.05) Varieties within Treatmentsempty table cell empty table cellempty table cell 5 5 (a) Values for each variety are the average of 4 replications. (b) Approximate conversion of ppm NO3-N to lb N/A can be ob­ tained by multiplying ppm NO3-N by 2. Table 4. Effect of rate of potassium and magnesium on yield, size, chip color and specific gravity of irrgated Russet Burbank and Sebago potatoes Potassium-Magnesium Potassium-Magnesium Potassium-Magnesium Application Application (a) Broadcas t lb K2O/A (a) Bande d lb K2O/A Potassium-Magnesium Application (a) Broadcas t lb Mg/A 0 0 60 120 180 420 0 60 120 0 60 60 60 60 60 60 60 60 0 0 0 0 0 0 50 50 50 Application (a) Total lb K2O/A 0 60 120 180 240 480 60 120 180 Russet Burbank Russet Burbank Total Over Yield 10 oz% (cwt/A)- Russet Burbank 10 oz- 1 7/8" % • Russet Russet Burbank Burbank Off Less than Type % 1 7/8"% Total Sebago Yield Sp. Russet Burbank Russet Burbank Chip Rating (cwt/A) Gr. Over Sebago 3 1/4"% Sebago Sebago 3 1/4" - 1 7/8" % Less than 1 7/8"% Sp. Sebago - Gr. 318 356 359 337 335 342 315 334 362 344 NS 45 25 25 29 26 29 31 23 27 30 28 NS NS 65 65 60 64 59 58 65 65 59 59 NS NS 5 6 6 3 6 4 7 4 5 6 5 5 5 6 5 7 5 5 5 7 6 5 5 6 6 4 5 6 5 5 NS NS -- -- NS NS 1.080 1.079 1.077 1.076 1.075 1.070 1.077 1.075 1.075 1.072 .003 .002 381 416 423 381 409 409 402 406 419 396 NS 45 7 9 9 11 10 10 9 11 9 11 NS NS 83 81 81 78 81 81 81 81 82 79 NS NS 10 10 10 11 9 9 9 8 9 9 NS NS 1.073 1.071 1.068 1.065 1.067 1.062 1.070 1.070 1.067 1.064 .003 .002 180 LSD (.05) treatments within varietiesEmpty table cell Empty table cell Empty table cell 240 60 50 LSD (.05) varieties within treatmentEmpty table cell Empty table cell Empty table cell (a) Potassium and magnesium sources were KCl and MgSO4 Planted: April 27, 1971 Row spacing: 32 inches Basic Fertilizer: 60-150-0, 180 lb N/A sidedressed June 10, 1971 Irrigation: 9.4 inches Previous crop: Sweet corn Harvested: Sept. 27, 1971 Seed spacing: Russet Burbank = 10" Sebago = 10" Soil test: pH = 6.4, P = 209, K range = 146-253 Harvest ares: 266 sq. ft Table 5. Effect of rate of potassium and magnesium on elemental composition of potato petioles. (Russet Burbank and Sebago varieties sampled 6-30-71) Treatment No. (a) 1 2 3 4 5 6 7 8 9 10 Elements (b) Elements (b) K % N % Elements (b) Elements (b) P % Elements (b) Ca % Ba Elements (b) Mg % Elements (b) Al Not Determined Not Determined Not Determined .50 .42 .43 .41 .49 .39 .42 .44 .42 .40 Not Determined Not Determined Not Determined Not Determined Not Determined Not Determined Not Determined 6.30 6.23 8.33 7.78 9.16 9.49 6.53 8.02 10.28 9.58 1.04 .74 .71 .76 .79 .75 .74 .74 .78 .72 100 .63 .56 .58 .60 .48 .73 .65 .68 .61 155 120 125 120 125 132 140 135 140 175 47 42 51 55 62 74 33 34 43 42 LSD (.05) Empty table cell NS NS .13 .16 26 18 (a) Treatments are the same as previous table. (b) Other elements which were not significantly affected by the treatments in this experiment: Na, Cu, Zn, Fe, B, & Mn. Table 6. Effects of different sources of potassium on yield, size, chip color and specific gravity of irrigated Russet Burbank and Sebago Potatoes. Source of Potassium (a) over Russet Burbank Russet Burbank Total 10 oz % Yield (cwt/A) 10 oz- 1 7/8" Russet Burbank Russet Burbank Russet Burbank Less than 1 7/8"% SebagoTotal Off Russet Burbank Type% Russet Burbank Sp. Yield Gr. (cwt/A) Chip Rating Sebago 3 1/4" - 1 7/8"% over Sebago 3 1/4"% % Sebago % Less than 1 7/8" None Potassium Chloride Potassium Nitrate Potassium Sulfate Potassium Carbonate 295 310 327 322 326 LSD (.05) treatments within varieties 42 LSD (.05) varieties within treatments 35 21 31 27 30 26 7 7 65 58 60 59 64 8 10 4 3 3 4 3 3 3 10 8 10 7 7 NS -- 5 6 5 5 5 NS — 1.083 1.077 1.077 1.076 1.079 342 426 424 434 421 .033 42 .004 35 5 10 11 9 10 7 7 84 80 81 83 82 8 10 11 10 8 8 8 3 3 (a) Applied at a rate of 300 lb K2O per acre broadcast and plowed down prior to planting. Planted: April 23, 1971 Row spacing: 32 inches Basic fertilizer: 120-150-0, 93 lb N/A broadcast and plowed down prior to planting Soil test: pH - 6.6, P = 316, K range = 153-258 Harvested: Sept. 27, 1971 Seed Spacing: Burbank = 14", Sebago = 10" Previous crop: Red clover Harvest areas: 266 sq. ft. Irrigation: 9.4 inches Sebago Sp. Gr. 1.072 1.066 1.069 1.068 1.069 .003 .004 Table 7. Effect of potassium carriers on elemental composition of potato petioles (Russet Burbank and Sebago Varieties samples 7-8-71) Treatment No. (a) 1 2 3 4 5 Elements (b) P Elements (b) N Not Determined Not Determined Not Determined Not Determined Not Determined .44 .48 .45 .44 .40 LSD (.05) Not Determined NS Elements (b) K Elements (b) Ca Elements (b) 5.86 9.04 8.58 8.43 8.27 1.29 .83 .66 .60 .62 .69 .13 Mg .98 .66 .58 .59 .64 .15 Zn Elements (b) Ba Elements (b) 37 45 35 53 40 8 42 46 44 22 54 18 (a) Treatments are same as in previous table. (b) Other elements which were not significantly affected by the treatments in this experiment: Na, Cu, Fe, Zn, B, Mn and Al. Table 8. Effect of different sources of nitrogen on yield, specific gravity chip color and size of irrigated Russet Burbank and Sebago potatoes Source of Nitrogen Total Russet Burbank Yield (cwt/A) Russet Burbank over 10 oz% Russet Burbank 10 oz- 1 7/8" % Russet Burbank Less than 1 7/8"% Russet Burbank Off Type% Russet Burbank Russet Burbank Sp. Gr. Chip Rating SebagoTotal Yield (cwt/A) Ammonium Sulfate (a) Ammonium Nitrate (a) Calcium Nitrate (a) Urea (a) Anhydrous Ammonia (b) LSD (.05) treatments within varieties LSD (.05) varieties within treatments 349 342 329 335 369 46 39 34 27 33 33 32 7 8 54 58 52 53 50 7 9 5 4 5 5 5 NS 1 7 11 10 9 13 NS -- 4 6 5 5 5 NS -- 1.076 1.076 1.077 1.078 1.077 .003 .003 413 420 393 446 390 46 39 (a) 180 lb N/A was top dressed May 19, 1971 just prior to emergence (b) 180 lb N/A was knifed in May 18, 1971 just prior to emergence Planted: April 23, 1971 Row spacing: 32 inches Basic fertilizer: 20-150-200, banded 2 inches to side and 2 inches below seed piece Irrigation: 9.4 inches Soil test: pH = 6.4, P = 348, K = 207 Harvested: Sept. 27, 1971 Seed spacing: Russet Burbank = 14", Sebago = 10" Previous crop: Sweet corn Harvest area: 266 sq. ft. Sebago over 3 1/4"% 17 16 14 14 14 7 8 Sebago 3 1/4" - 1 7/8" % 75 77 78 78 78 7 9 Less than Sebago 1 7/8"% 8 7 8 8 8 NS 1 Sebago Sp. Gr. 1.066 1.066 1.068 1.067 1.064 .003 .003 Table 9. Summary of yield results for nitrogen carrier experiment. Source of Nitrogen Ammonium Sulfate Ammonium Nitrate Calcium Nitrate Urea Anhydrous Ammonia (1968-1971) (1968- 1971) average 4 year 4 year average Russet Burbankcwt/A Sebago (1967-1971) (1967-1971) average 5 5 year average Russet Burbank cwt/A year cwt/A Sebagocwt/A 296 290 264 291 301 348 347 346 370 364 277 277 253 332 327 321 269 ___ (a) 345 ___ (a) (a) 5 year average is not available. Table 10. The effect of liquid, dry, poly and ortho-phosphate ferti­ lizers on yield, and size of irrigated Russet Burbank potatoes. % " 8 / 7 % " 8 / 7 n a h t s s e L 1 1 % e p y t f f O Total Yield (cwt/A) % z o r e v O 0 1 10 oz- 255 269 279 270 241 261 NS 258 267 274 251 14 17 15 13 11 13 NS 13 14 14 12 59 50 56 53 52 56 NS 56 53 54 54 9 10 9 9 11 9 NS 10 9 9 10 17 24 20 24 26 22 NS 21 23 22 24 n-p2o5-k2o Rate lb/A 50-0-0 50-0-0 Treatment Liquid N (28%) Dry N (32%) Liquid poly-P + N 50-100-0 Dry poly-P + N 50-100-0 Liquid ortho-P + N 50-100-0 Dry ortho-P + N 50-100-0 LSD (.05) TreatmentsEmpty table cell Liquid average (a) Dry average (a) Empty table cell Empty table cell Polyphosphate average (b) Empty table cell Empty table cell Orthophosphate average (b) (a) These are the averages of the three liquid and dry fertili­ zer treatments. (b) These are the averages of the two poly and ortho-phosphate treatments. Planted: May 5, 1971 Row Spacing: 34 inches Broadcast Fertilizer: 70-0-120 Sidedress N: 70 lb N/A just prior to hilling. Irrigation: 8.0 inches Soil tests: pH = 6.6, P = 189, K = 216 Harvested: September 28, 1971 Seed Spacing: 14 inches The Effect of Harvest Date and Storage on the Yield Potential of Onaway and Sebago Seed Potatoes R. W. Chase Department of Crop and Soil Sciences Procedure This is the second year of this study to determine the harvest and storage factors which can influence potential seed quality. Seed of the Onaway and Sebago varieties was harvested at several different harvest dates and placed in storage at East Lansing either directly into a 40F environment or stored for 7-10 days at 60-65F and then placed in the 40F storage. Prior to planting (approximately 2 weeks) the seed was warmed to 50-55F, cut and then hand planted with a uniform spacing and number of seed pieces per plot. Both varieties were planted on May 4, 1971 at a 10" spacing. Fertilizer applied consisted of plowdown 70-0- 120 lb/A, 800 lbs per acre of 14-14-14 plus 2% Mg and 70 lb N/A side­ dress. A summary of the 1970 harvest and storage conditions is as follows: OnawayOnaway Empty table cell Topkill 1 2 3 4 5 6 7 ----- ------ Aug 5 ----- ----- Aug. 24 ----- SebagoSebago ----- ----- 1 2 3 4 5 6 7 Aug. 24 ----- ----- Sept. 16 Oct. 8 Oct. 8 ----- Onaway Onaway Harvest Date Aug. 5 Aug. 5 Sept. 16 Aug. 24 Aug. 24 Sept. 16 Sept. 16 Sebago Aug. 24 Aug. 24 Oct. 8 Sept. 16 Sept. 16 Storage Condition ◦F 40 70-40 40 40 70-40 40 40 Sebago 40 70-40 40 40 70-40 40 40 Onaway Days Growing Onaway Days to Harvest 91 91 91 110 110 110 133 Sebago 110 110 110 133 133 133 155 91 91 133 110 110 133 133 Sebago 110 110 155 133 133 155 155 Results and Discussion Table 1 summarizes the Onaway yield data. The lowest yields did occur with treatments 1, 3 and 7. The reduced yield of treatment 1 is due primarily to the physical condition of the seed at planting time. This was the earliest harvested seed and consequently the most immature. Placing this seed directly into a 40F storage allowed no wound healing and the seed at planting time was badly shrivelled and damaged. Treatment 4 which repre­ sents the next stage of harvest did not show the same physical defects at planting time even though it was stored at 40F. Needless to say, the curing period is essential to maintain sound tuber quality particularly if the tubers are immature. Treatment 3 represents early topkill and leaving the tubers in the ground for an additional 5 weeks. This did result in reduced yields which follows the same pattern as the 1970 results. Apparently some loss in seed vigor results when seed tubers are left in the ground for an extended period after top killing. Similarly there was a reduced yield from treatment 7 seed which was allowed to grow until the 133 day harvest. Table 2 summarizes the Sebago observations. The lowest yields did occur with treatments 1, 4 and 7. The lowered yield of treatment 1 was because of the poor physical condition of the seed just as was observed with the Onaway. Allowing the seed to heal as was done in 2 did retain the seed in a sound physical condition. Treatment 4 had a reduced yield also and it is suspected that the Sebago which is a late maturing variety was still relatively immature at the 133 day harvest and the 40F environment did not allow for wound healing and conditioning. Allowing the seed to go to full maturity at 155 days did result in a reduced yield compared to the earlier harvests and properly conditioned seed however to a lesser degree than was noted with Onaway. Notes made at 30 days after planting showed considerable differences in emergence, uniformity, and plant vigor. With the Onaway the most vigorous and uniform plants were observed with treatments 2, 5 and 6. The poorest vigor was observed with treatments 1, 3 and 7. With the Sebago, treatments 2 and 5 were much more vigorous whereas treatments 4 and 7 were the poorest. This study will be continued one more year at which time it will be summarized and terminated. Table 1. Effect of Harvest Date on the Yield Potential of Onaway Seed. Empty table cell No. Days Growing No. Days to Harvest Storage Temp. Total Cwt/ A Percent Size Distribution -1 7/8" Percent Size Distibution Percent Size Distribution 1 7/8"-3 1/4" + 3 1/4" 1. 91 2. 91 3. 91 4. 110 5. 110 110 6. 7. 133 91 91 133 110 110 133 133 40 70-40 40 40 70-40 40 40 296 361 309 342 364 344 319 3.3 2.8 3.8 3.4 3.7 4.7 4.2 Table 2. Effect of Harvest Date on the Yield Potential of Sebago Seed. 1. 110 2. 110 3. 110 4. 133 5. 133 6. 133 7. 155 110 110 155 133 133 155 155 40 70-40 40 40 70-40 40 40 310 361 342 319 337 345 329 5.1 4.5 5.4 3.7 4.5 4.6 4.8 73.5 69.8 73.3 70.1 74.0 75.3 73.0 70.3 73.5 69.1 72.6 73.8 69.2 68.3 23.2 27.4 22.9 26.5 22.3 20.0 22.8 24.6 22.0 25.5 23.7 21.7 26.2 26.9 Plant Spacing Studies R. W. Chase and N. R. Thompson Department of Crop and Soil Sciences Procedure Three of the most advanced new seedlings from the Michigan breed­ ing program were observed in terms of optimum plant spacing. The seedling identification numbers are 711-3, 503 and 709. Planted: April 27, 1971 Fertilizer: plowdown planter sidedress (6/10/71) 200 1bs/A 200 lbs/A 800 lbs/A 200 lbs/A 33.5-0-0 0-0-60 14-14-14 + 2% Mg 33.5-0-0 Cut seed of each seedling was hand planted at spacings of 7, 10, 13 and 16 inches within the row. Row width was 34 inches. Each plot was 10 feet long and replicated four times. Results Table 1 gives a summary of the yield, size distribution and specific gravity response. Each of the seedlings responded differently in terms of these measurements. For example, 709 produced the greatest total and marketable yield at the 7 inch spacing. The 10 and 13 inch spacings were quite similar in yield and also produced the greater percentage of tubers over 3 1/4 inches. This seedling does have a tendency to develop large tubers so a spacing somewhere in the 7-8 inch range seems desirable depending on the level of total management. Seedling number 503 was the lowest yielding of the three. Its most favorable response occurred in the 10-13 inch spacing. The seedling sets heavier than 709 and therefore appears to require a wider space in order to adequately size the tubers. Oversize does not appear to be a problem with this seedling. The 711-3 seedling responded most favorably at the 10 inch spacing with a higher percentage of tubers in the 1 7/8 - 3 1/4" category. An interesting response was observed in terms of the specific gravity readings. In each of the three seedlings, the lowest readings occurred at the 16" spacing. With 709 and 503 the highest reading occurred at the 7" spacing. The differences in growth were noticeable throughout the growing season. In all cases the closest spacing was the quickest to emerge and the plants seemed to show considerably more vigor than did the wider plantings. This trend occurred through to maturity. On August 20 observations were made on relative degrees of maturity. Seedling 503 was the most mature and only some green in the stems still remained. The 711-3 was next in maturity with considerable yellowing showing. The 709 vines were down but still had a considerable amount of green foliage. Lower leaves were yellow. When maturity observations are considered as it relates to the subsequent yields it appears that 709 does set and develop its tubers earlier than does 503 or 711-3. Table 1. The yield, size distribution, and specific gravity of three seedlings when grown at different plant spacings. In-Row Space (inches) Total Cwt/A Seedling Total Greater than 1 7/8 Cwt/A Percent Size Distribution -1 7/8 Percent Size Distribution +3 1/4 Percent Size Distribution 1 7/8-3 1/4 Spec. Gravi 709 503 709 709 709 503 503 503 711-3 711-3 711-3 711-3 7 10 13 16 7 10 13 16 7 10 13 16 387 360 357 324 282 273 273 223 290 314 281 264 375 346 346 314 223 224 235 185 247 276 244 240 3 4 3 3 21 18 14 17 15 12 13 9 19 35 30 19 6 5 7 1 0 0 5 8 78 61 67 78 73 77 79 82 85 88 82 83 1.076 1.074 1.073 1.073 1.076 1.071 1.073 1.070 1.089 1.089 1.089 1.085 Potato Vine Killing Results in 1971 R. W. Chase, W. F. Meggitt and R. C. Bond Department of Crop and Soil Sciences Chemicals were applied on two varieties for killing tops prior to harvest. The varieties, chemicals and dates of application are listed in Table 1 and 2. Treatments were applied in 50 gal of water per acre. Plot size was 3 rows by 50 ft. Samples were taken for storage quality and chipping evaluation. A number of chemicals provided satisfactory vine kill. Currently the only materials registered are dinoseb (DNBP or General) and para­ quat. Crop oil or crop oil concentrates were the most effective additives used with the dinoseb. Heavier and less mature vines require dinoseb at 2 qt/A whereas 1 1/2 qt is sufficient where vines have begun natural maturing. There were no observable differences in the chipping quality from any of the vine killing treatments. Table 1. Chemicals for Potato Vine Killing, Montcalm County, 1971 Trt. No. Chemical Rating* Rating* 5 day Rating* 13 day 1 day Rating*Weeds Ametryne Ametryne + Crop Oil Ametryne + Crop Oil Ametryne + Crop Oil Des-i-cate Rate/A 2 lb 2 + 1 gal 4 4 + 1 1 gal Des-i-cate + Crop Oil Des-i-cate + Crop Oil Des-i-cate + Crop Oil Rhodia 2929 Rhodia 2929 + Crop Oil 1 gal + 1 gal 2 2 + 1 3 lb 3 + 1 gal Rhodia 2929 Rhodia 2929 + Crop Oil Paraquat General + Crop Oil General + Crop Oil 4 4 + 1 2 pt 1 1/2 qt + 1 gal 2 + 1 2.7 4.3 4.7 6.3 5.7 General + fuel oil General + fuel oil General + Tronic General + Tronic General + Agri-Oil Plus 1 1/2 + 5 gal 2 + 5 1 1/2 + 1 pt 2 + 1 2 + 1 qt General + U.C. #4 General + U.C. #5 General + R558 MO No Treatment 2 + 1 qt 2 + 1 qt 2 + 1 qt ------ 4.7 5.7 4.3 5.3 5.7 6.0 5.7 6.7 2.0 2.0 3.0 2.7 3.3 3.3 3.7 3.3 4.7 2.7 4.0 4.3 5.7 5.3 6.0 6.7 6.3 6.0 7.0 5.3 6.0 5.0 6.3 7.3 7.7 7.7 6.0 7.7 6.3 6.7 7.3 7.3 7.3 8.0 3.7 10.0 10.0 10.0 10.0 9.7 9.3 9.7 9.7 8.7 9.3 8.7 9.7 10.0 10.0 9.3 9.3 10.0 9.3 9.7 9.7 9.7 9.3 10.0 7.0 10.0 9.3 9.7 10.0 4.7 5.3 7.7 7.7 4.7 6.7 7.0 5.3 9.7 7.7 7.7 6.0 7.0 4.7 8.3 7.3 7.3 6.7 8.3 5.0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 * 0 - no kill 10 - complete kill Variety - Onaway Treated - August 5, 1971 Table 2. 1971 Vine Kill Treatments, Montcalm Experimental Farm Rate / A 2 lb 2 lb + 1 gal 1 1/2 gal 1 1/2 gal + 1 gal 3 lb 3 lb + 1 gal 2 pt + .1% 1 1/2 qt + 1 gal 2 qt + 1 gal 1 1/2 qt + 1 qt 2 qt + 1 qt 1 1/2 qt + 5 gal 1 1/2 qt + 1 qt 1 1/2 qt + 2 qt 1 1/2 qt + 1 qt 5 day* Rating 7.0 6.3 7.0 8.0 8.3 8.7 7.3 9.3 8.7 8.0 9.0 8.3 8.7 8.7 7.0 3 qt of mixture 1/3 fuel oil 1 1/2 qt + 1 qt 8.7 7.7 1 1/2 qt 9.0 1 1/2 qt + 3/4 lb + 1 gal 8.7 2 qt + 3/4 lb + 1 gal 8.7 1 1/2 + 3/4 + 1 qt 2 qt + 3/4 lb + 1 qt Empty table cell ----- Empty table cell 7.8 8.7 9.3 4.7 7.0 Trt. No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Chemical Ametryne Ametryne + oil Des-i-cate Des-i-cate + oil Rhodia 2929 Rhodia + oil Paraquat + X77 General + oil General + oil General + agri oil plus General + agri oil plus General + fuel oil General + R558 MO General + R558 MO General + Tronic General + U. C. #4 General E/emulsifier General General + Kocide 101 + oil General + Kocide 101 + oil General + Kocide 101 + Agri oil plus General + Kocide 101 + Agri oil plus Formulated General Check - no treatment Flame - LP gas * 0 - no kill 10 - complete kill Variety - Russet Burbank Treated - September 2, 1971 Potato Breeding N. R. Thompson Department of Crop and Soil Sciences Segregating Populations First year seedlings comprised 4200 individual cultivars from 9 cross pollinations and one self-fertilized family. After a very slow start, growth was rapid and vigorous. The appearance of aphids required that the vines be killed September 6 when 20% of the plants were still in full bloom. This immaturity accounted for the lower than anticipated specific gravity of many cultivars. However, in the first year with only one hill of a cultivar it is essential that the spread of viruses be controlled or many good cultivars will be lost. Shape, size and general appearance was exceptionally good and a greater than normal number were retained. Quality studies, i.e., total solids, chip color, and storage tests will determine the cultivars to be planted in 1972. If the random sampling of 50 selections (Table 1) from each cross is represen­ tative between 2500 and 3000 will be saved. Table 1. Average performance of 50 randomly selected samples from ten segregating seedling populations. Cross No. Parentage Yield lbs/hill Low Yield lbs/hill Av. Yield lbs/hill High Specific Gravity Low Specific Gravity Av. Specific Gravity High Chip ColorLow Chip color Av Chip Color High 0.18 1.7 320-6 x 709 0.26 1.6 321-38 x 709 0.17 1.9 321-65 x 709 1.4 321-70 x 709 2.4 0.85 2.5 706-34 x 709 706-34 x 706-32 0.79 2.6 706-34 x 711-8 1.05 2.4 706-34 x 735-1 1.32 3.0 0.89 2.3 1.01 2.4 001 002 003 004 005 006 007 008 009* 709 x 010 Av. Empty table cell *7 samples only 711-8 x 735-1 Empty Table cell 2.28 Empty table cell 4.7 3.8 5.7 4.5 6.5 5.1 5.2 6.0 4.5 4.6 1.075 1.083 1 3.8 1.062 1.067 1.082 1.143 2 3.5 1.074 1.089 1.144 1 3.1 1.075 1.087 2 4.3 1.061 1.054 1.073 1.089 1 3.9 1 4.8 1.059 1.070 1.089 1.082 1 4.0 1.048 1.067 1.054 1.068 1.083 3 5.7 1.080 3 5.0 1.060 1.071 1.090 1 4.8 1.049 1.071 7 6 6 7 8 7 8 9 6 9 Empty table cellEmpty table cell Empty table cell Empty table cell 4.29 Empty table cell The continued backcrossing of the S. stoloniferum hybrids seems to have eliminated the wild characteristics while retaining the high total solids and chip quality. Shape and yield of the S. tuberosum parent was clearly evident in the progeny. These seedlings will be analyzed for protein and methionine. Methionine is the essential amino acid which most commonly limits the total nutritive value of the potato. Protein and methionine content of the parental clones is presented in Table 2. Several S2 selections from an inbred popula­ tion of the variety Merrimack are shown in Table 3. Five thousand new cultivars of similar genetic background have been grown in the greenhouse for planting in 1972. Table 2 Keildahl Protein and Methionine of Parental Clones 1971 Protein % N x 6.25/d.m. Available Methionine % met/N x 6.25 9.2 14.4 13.0 10.8 15.2 9.5 7.8 12.6 1.05 1.25 1.45 1.20 1.45 1.25 1.1 1.35 Cultivar 735-1 321-38 321-70 320-6 706-34 709 371-65 711-8 Table 3 Inbred Merrimack Population, 1971 Protein % N x 6.25/d.m. Available Methionine % met/N x 6.25 11.6 10.1 14.7 12.5 11.8 10.1 11.2 12.2 11.6 15.1 2.5 2.3 1.8 2.25 1.8 1.61 1.19 1.40 1.54 1.55 Cultivar 854-1 852-18 854-28 864-56 866-7 866-13 864-19 Merr. 114 Merr. 132 Merr. 249 Merr. 249, yielding 29, 200 lbs/acre with a protein content of 3.5% on a fresh weight basis yielded 1022 lbs protein per acre. Advanced Clones For varietal potential 35 cultivars were evaluated. Ten hills of each were dug early for seed increase. The balance were killed September 6 and harvested for yield quality and storage studies, Table 4. Chipping tests in January after reconditioning from 45°F storage, dor­ mancy, baking, boiling and french frying will determine which of the culti­ vars will be screened for diseases in the greenhouse prior to increase on the Coleman Farms, Marquette. Table 4. Advanced Seedling Clones. Clone No. 735-1 706-34 613-18 859-144 *321-101 706-1 711-8 645-1 613-20 645-2 *321-30 1111-2 623 613-27 Merr 114 613-7 *321-55 613-9 Yield, cwt/A cwt/A Yield, B's US #1 Yield, cwt/A Total Specific Gravity Chip Color 866 736 616 585 513 533 543 508 462 508 462 451 393 354 391 369 354 339 00 28 51 30 102 60 29 41 77 30 61 11.0 25 57 12 31 45 48 866 764 667 615 615 593 572 549 539 538 523 462 418 411 403 400 389 387 1.076 1.063 1.064 1.079 1.083 1.074 1.068 1.075 1.074 1.074 1.090 1.070 1.070 1.059 1.078 1.067 1.106 1.067 5 8 5 5 2 2 4 2 2 2 3 3 1 3 3 6 2 4 *Derived from S. stoloniferum hybrids. Several of the cultivars have been in overstate yield trials or seedling trials for three or more years and will be increased for commercial testing as soon as possible. MS 735-1 - A slightly elongated smooth white skinned seedling with shallow eyes and a very high yield potential. Primarily a table potato. MS 706-34 - A round white table potato with a consistently high yield potential; tends to be slightly rough especially the large tubers. MS 711-8 - A smooth oval shaped tuber that retains its shape; stores well for table stock market. MS 706-1 - A round white with chip processing characteristics. Medium total solids but color is uniform and good; stores well. 1971 Overstate Potato Variety Trials R. W. Chase and N. R. Thompson The 1971 overstate potato variety trials were conducted at 4 locations: Shoemaker Bros, in Allegan County; Don Meyers in Bay County; Delekta Bros, in Presque Isle County; and the Montcalm Experimental Farm. Growing conditions in each location were quite variable and undoubtedly reflects the differences in variety performance between locations. Table 1 summarizes the overall response when all of the data from the 4 locations are averaged. Table 2 provides the variety data at each of the locations. Table 1 does not include the specific gravity readings from the Presque Isle location. A look at the data from this location in Table 2 reveals specific gravity readings which appear to be abnormal. This location did receive considerable rainfall throughout the growing season which may have resulted in the lower-than-expected readings. Two of the locations were irrigated - the Montcalm Experimental Farm and the Bay locations. The Allegan trial was on an organic soil. Planting and harvest dates for each location are as follows: Bay County, April 28 and August 30; Allegan County, May 14 and October 1; Presque Isle, May 29 and October 11; and Montcalm Experimental Farm, April 27 and September 7. Plant spacings at all locations were 12 inches. Table 1. The average yield, size distribution and specific gravity of several potato varieties grown at four locations. Size Distribution Percent Size Distribution Percent Size Distribution Percent +3 1/4 1 7/8-3 1/4 Variety Abnaki Sioux MS-709 Jewel Onaway Norchip Shurchip Cascade Alamo Wauseon Iopride MS 711-3 MS-58 MS-1111-2 Katahdin York MS-503 Total Cwt/A 447 430 396 396 388 379 366 364 353 346 335 331 329 297 294 288 286 -1 7/8 5.3 6.1 5.5 10.3 5.6 6.6 9.8 5.3 10.3 7.1 10.0 9.6 8.3 7.0 9.0 5.4 15.7 27.3 23.2 33.5 10.2 27.2 21.4 15.9 13.5 9.0 20.5 12.7 12.0 15.5 24.9 18.5 22.1 5.6 67.4 70.7 61.0 79.5 67.2 72.0 74.3 81.2 80.7 72.4 77.3 78.4 76.2 68.1 72.5 72.5 78.7 Specific Gravity 1.076 1.081 1.074 1.086 1.071 1.079 1.071 1.073 1.065 1.073 1.069 1.086 1.081 1.064 1.073 1.071 1.073 Average 354.4 Empty table cellEmpty table cellEmpty table cell Empty table cell Table 2. The yield, size distribution and specific gravity of several potato varieties grown at 4 locations. ALLEGAN CO. BAY CO. Total Cwt/A Percent Percent +3 1/4 Percent 1 7/8-3 1/4 -1 7/8 Sp. Gr. Variety Total -1/78 Cwt/ A Percent Percent +3 1/4 nt Perce 1 7/8-3 1/4 Sp. Gr. 488 454 395 373 371 367 351 334 326 303 314 306 293 275 264 243 4.4 13.7 9.4 6.3 6.3 8.5 6.7 8.2 8.3 14.2 8.1 6.4 5.4 7.8 6.0 12.0 38.0 2.0 16.3 19.9 23.2 31.4 21.1 15.8 22.2 4.5 33.5 26.1 33.3 2.1 20.7 2.4 57.6 84.3 74.3 73.8 70.5 60.1 72.2 76.0 69.5 81.3 58.4 67.5 61.3 90.1 73.3 85.6 1.077 1.084 1.071 1.073 1.078 1.069 1.076 1.068 1.073 1.066 1.072 1.071 1.065 1.086 1.074 1.078 488 Abnaki 473 Jewel 387 Shurchip 433 Cascade 435 Norchip 394 Onaway 493 Sioux 363 Iopride 496 Haig 466 MS-709 376 Katahdin 332 MS 711-3 MS 1111-2 329 301 MS-503 5.8 14.1 17.3 5.4 10.0 4.0 5.7 10.7 7.8 7.7 9.5 16.4 14.2 31.1 36.7 8.3 8.1 10.8 15.4 30.8 34.2 16.3 10.4 29.4 18.7 6.1 6.2 0 57.5 77.6 74.6 83.8 74.6 65.2 60.1 73.0 81.8 62.9 71.8 77.5 79.6 68.9 1.078 1.091 1.073 1.077 1.081 1.075 1.084 1.069 1.075 1.073 1.071 1.081 1.063 1.070 Variety Abnaki Jewel Shurchip Cascade Norchip Onaway Sioux Iopride Wauseon Alamo MS-709 York MS 1111-2 MS 711-3 Katahdin MS-503 Table 2. (Continued) Montcalm Experimental Farm Presque Isle County Variety Total -1 7/8 Cwt/A Percent Percent Percent 1 7/8-3 1/4 +3 1/4 Sp. Gr. Variety Total Cwt/A Percent -1 7/8 Percent Percent 1 7/8-3 1/4 +3 1/4 Sp. Gr. 437 Onaway 423 Sioux 407 MS-709 Abnaki 379 373 Iopride 351 Jewel 345 Cascade MS-711-3 328 328 Norchip 324 MS-58 306 Shurchip 285 Katahdin MS 1111-2 275 248 MS-503 2.7 5.5 4.3 5.1 5.7 6.7 4.0 9.5 7.2 10.2 8.9 10.3 5.7 15.0 13.8 17.4 31.1 11.9 8.4 7.2 9.6 1.8 8.3 0 9.6 20.5 17.0 7.8 83.5 77.1 64.6 83.0 85.9 86.1 86.4 88.7 84.5 89.8 81.5 69.2 77.3 77.2 1.070 1.081 1.075 1.073 1.070 1.083 1.070 1.089 1.078 1.081 1.067 1.075 1.065 1.072 454 Sioux 402 Alamo 395 MS-709 MS 711-3 387 Norchip 381 374 Shurchip 365 Wauseon 363 Abnaki 353 Onaway 351 MS-503 334 MS-58 304 Cascade 303 Jewel MS 1111-2 289 270 York 270 Iopride 250 Katahdin 6.4 6.3 2.0 4.5 3.0 3.6 5.9 5.9 7.2 5.0 6.4 5.7 6.5 2.7 4.4 15.3 10.1 20.2 13.6 40.1 38.2 38.5 29.7 18.7 22.6 32.6 12.2 31.0 13.5 23.2 43.2 18.1 10.1 14.1 73.4 80.1 57.9 57.3 58.5 66.7 75.4 71.5 60.2 82.8 62.6 80.8 70.3 54.1 77.5 74.6 75.8 1.066 1.056 1.064 1.068 1.070 1.062 1.065 1.066 1.060 1.065 1.058 1.063 1.067 1.062 1.069 1.063 1.067 Following are the general observations of each of the varieties: Abnaki - released in 1970 by the U.S.D.A., New York and Main. In all locations the yields and size distribution and general appearance were exceptionally good. Tubers over 3 1/4 inch were common, however, they were not rough nor off-type. A closer spacing would help correct this factor. Specific gravity is medium; maturity is late; the tubers are round and somewhat flattened; and the skin was noted to be slightly netted at some locations. Abnaki is reported to be resistant to Verticillium wilt, mild mosaic and leaf roll. No hollow heart was observed. Sioux - released in 1969 by Nebraska. This was the only red skin variety in the trials. The tubers have a slightly scaly russeted skin; are round and slightly flattened; and a fairly shallow eye. The yields, size distribution and general appearance were very good. Dry matter content was high. Maturity is similar to Kennebec. Sioux is reported to be resistant to scab, but is susceptible to Fusarium and Verticillium wilt and late blight. MS-709 - a Michigan seedling which will be released in 1972. Maturity is early (similar to Onaway) and medium dry matter. It has a smooth white skin, shallow eyes, and very acceptable appearance. At the 12 inch spacing used in these trials, the percent over 3 1/4" was considerable, however, a closer spacing would correct this concern. These oversize tubers did not go off-type and hollow heart was not observed to be a concern. It does produce an acceptable chip out-of- the-field, however, it is not suggested for chipping out-of-storage. Jewel - released by private breeders in New York in 1968. This variety has a very high dry matter content. Jewel is reported to have no disease resistance. Despite this it has continued to perform well in our trials. The tubers are white skinned; round and flattened; and shallow eyed. Maturity is similar to Kennebec. Onaway - used as a standard early maturing variety. Tubers were more off- type and irregular than in other years. Norchip - tuber shape and appearance this year were not as uniform and attractive as in other years. Some irregular shapes and off-types. Yields were favorable and dry matter content was medium-high. Shurchip - released in 1969 by Nebraska. This variety does have a high yield potential. The tubers do have a scaly russet on the skin. The tubers are elongated and somewhat flattened in appearance. Specific gravity was medium to medium low. Shurchip is reported to be resistant to scab and tolerant to Fusarium and Verticillium wilts. The foliage is susceptible and the tubers are highly susceptible to late blight. Cascade - released in 1969 by the U.S.D.A. and Washington. This variety yielded about average with a medium specific gravity. It is a round white variety with a slightly netted skin and a favorable general appearance. The variety is reported to have moderate resistance to Verticillium wilt and the leaf roll virus. Maturity was about medium. Alamo - released in 1967 by the U.S.D.A. and Texas. The tubers are somewhat elongated, have a smooth white skin and a medium eye depth. It appeared in this years trials to set heavy and this is reflected in the size distribution. Its maturity is medium early and has resistance to late blight, common scab, net necrosis and mild mosaic. Wauseon - released in 1967 by the U.S.D.A. and New York. The tubers have a smooth white skin with a very slight netting on some soils. It has a round and somewhat flattened shape. It is a late maturing variety and has resistance to golden nematode and moderate resistance to common scab, latent and mild mosaics and net necrosis from current season leaf roll infections. Iopride - was released in 1970 by Iowa. Maturity is medium early and the tubers were slightly netted in most locations. This variety performed about average in these trials and was medium to low in specific gravity. MS-711-3 - an unreleased Michigan seedling. The tubers are rounded with a very slight net showing at some locations. Tubers lacked uniformity in type and shape. Maturity is similar to Kennebec and it was one of the highest in specific gravity readings. It has a high dry matter and is a good processor. MS-58 - an unreleased inbred Merrimack from the Michigan program. It is a late maturing seedling which does have a high dry matter content. It has a good balance of protein for human nutrition as it is high in methionine - one of the amino acids commonly deficient in potatoes. MS-1111-2 - an unreleased Michigan seedling which has an early maturity. Katahdin - included as a standard late maturing variety. In all locations this variety yielded well below average which is not typical of its usual performance. It is suspected that there must have been some loss in seed quality although its physical appearance did not indicate any concerns. York - released in 1969 by Canada. The tubers had considerable netting at most locations, were round and slightly flattened and had a rather shallow eye depth. This variety was included at only the Allegan and Presque Isle locations and performed well below average at both locations. In the release description it is classed as early maturing and high total solids. Gravity readings at these two loca­ tions would rank it as medium to low. In Canadian trials it has per­ formed best on the organic soils. MS-503 - an unreleased Michigan seedling. Water Management of Potatoes R. J. Kunze and Ana Garay Department of Crop and Soil Sciences This is a joint project between several departments with Dick Chase of this department and Ernie Kidder from Agricultural Engineering actively involved both in the planning and development stages. Ana Garay is a doc­ torate student from Argentina. To carry out her assigned duties it was necessary that she spend full time on this project and we are greatly indebted to the Theron Comden's for providing living facilities which enabled her to give complete attention to her summer duties. All concerned with the project appreciate their cooperation and helpfulness. The project is a two-year study and has four objectives: 1. To measure the yield difference resulting from either day or night irrigation. 2. To measure the effects of two levels of irrigation cooling. 3. To determine if timing of the initial irrigation affects tuber initiation, quality and yield. The initiation of irrigation in 1971 commenced 50, 60, and 70 days after planting. 4. To devise an accurate, inexpensive scheme for determining irrigation frequency. Procedure Russet Burbank and Kennebec potatoes were planted on April 30, 1971. The fertilization program consisted of the following amounts in pounds/acre: 70N-120K at plow-down, 110N-110P-110K-16Mg banded at planting, and 70N as sidedressing before hilling. Disyston at 3 lb/acre was also applied at planting. Potatoes were harvested on September 21. The early part of the growing season was very dry so that all objectives had great potential of showing real differences. A small weather station for recording rainfall, pan evaporation, temperature, relative humidity, wind velocity and solar radiation was set up adjacent to the plot area. Electrical power was needed for operating several instruments and a small electrically driven irrigation pump. Irrigation of small plot areas was accomplished with the use of garden sprinkler hoses. These were fastened onto elevated irrigation pipe and the pipe was rotated to compensate for wind velocity and direction. The irrigation water was stored in a 4' x 15’ diameter swimming pool. This pool was filled intermittently from a well-pump as needed. All plot areas were irrigated on a time basis. Four irrigation volume meters were purchased to provide equal application of water but these did not arrive in time to be of any benefit in 1971. Because of inadequate seals and much leakage from normal irrigation pipe, the entire system was converted to a 2 inch plastic pipe system on July 26, 1971. This system was completely water tight and performed flawlessly for the remainder of the season. The entire cost of this system was less than the fittings alone for the aluminum pipe system. Results Table 1 shows a very definite trend between yield and the timing of the first irrigation of Russet Burbank potatoes. The potatoes in treatment 1 were first irrigated 50 days after planting, treatment 2 - 60 days after planting and treatment 3 - 70 days after planting. Treatment 1 received 10 one-inch irrigations; treatment 2 received 8; and treatment 3 received 6. Yields decreased with delayed irrigation. However, water added at a late stage was increasingly more beneficial in terms of yield per inch of water applied. The same general trends exhibited in the yield data is also demonstrated in the specific gravity data. The percentage of off type or knobby potatoes was closely correlated with the amount of water added to the Russet Burbank. There appears to be no trend in day versus night irrigation in terms of yield, however percentage of knobs seems to be slightly higher with night irrigation. The same general trend between yield and treatment exhibited by the Russet Burbank potatoes is also true for Kennebec as shown in Table 2. The yield differences are larger for day irrigation but smaller for night irri­ gation. Specific gravity values are lower than those for the Russet Burbank but follow the same general trend. A very simple way of determining the proper time to irrigate is shown in Figure 1. The slope of the upper diagonal line represents the average loss of water per day by evapotranspiration as determined by pan data. The width span between the two diagonal lines represents the amount of plant-available water that can be stored in a McBride sandy loam soil. The vertical dashed lines represent inches of irrigation applied and the solid vertical lines the Table 1. Average yields and specific gravity of Russet Burbank potatoes under day and night irrigation (1971). Empty table cell Day Day Night Night Yield cwt/A 197.6 326.7 299.6 295.4 Sp. Gr. 1.0695 1.075 1.0737 1.0725 % Knobs 41.4 12.4 14.3 19.9 Yield cwt/A 160.2 341.7 304.4 290.4 Sp. Gr. 1.0677 1.0762 1.074 1.0697 % Knobs 45.3 14.5 15.5 23.2 Check 1 Treatment 1 Treatment 2 Treatment 3 Table 2. Average yields and specific gravity of Kennebec potatoes under day and night irrigation (1971). Empty table cell Yield cwt/A 184.8 353.8 288.0 280.5 Day Day Specific Gravity 1.063 1.067 1.0617 1.059 Night Night Specific Gravity 1.0627 1.0672 1.065 1.0625 Yield cwt/A 147.5 304.1 324.5 291.1 Check Treatment 1 Treatment 2 Treatment 3 Table 3. Effect of irrigation cooling on yields and specific gravity of Russet Burbank and Kennebec potatoes (1971). Empty table cell Bubank Russet Russet Bubank Specific Yield cwt/A Gravity Kennebec Kennebec Yield cwt/A Specific Gravity Check Treatment 1* Treatment 2** 265.8 315.9 374.7 1.0727 1.0763 1.0752 265.0 315.0 324.8 1.0607 1.0637 1.065 *When ambient temperature higher 75° F **When ambient temperature higher 80° F Fig. 1 SOIL AVAILABLE WATER IN 1971 (TREATMENT 1) frequency and amount of precipitation. For each day without irrigation or rainfall a line of 1 unit length is drawn horizontally. When the horizontal line approaches the lower diagonal line, the soil has a deficit of plant- available water, and lacking rainfall, additional water must be added by irri­ gation. The same is true when a quantity of water is added that would cause a vertical line to go beyond the upper diagonal line. This is excess water and it will be lost by flow through the soil profile to a depth beyond the range of plant roots. The irrigation plan shown here was developed on the basis of daily evaporative losses from a class A weather pan. The daily evaporative losses varied from almost zero to .5 inch per day. When averaged over the entire summer about .2 inch was lost per day. Yet when this irrigation management plan is tested as shown in Figure 1 it does a very good job of predicting when a potato farmer should irrigate. Significant differences appear to exist in yield for both potato varieties when they were irrigated cooled; however, large variations were found in the check data (see Table 3). Although these potato plots were irrigated 15 times via the farm irrigation system, and in general received about 12 inches of water, there is some question as to how well the water was distributed. The irrigation cooling system was running only 5 minutes out of 30 and in 34 days of irrigation cooling on treatment 1 only 2.3 inches of water were applied. In treatment 2 there were 14 irrigation cooling days resulting in 1 inch of water applied. No explanation can be given why yields from treat­ ment 1 were lower than those of treatment 2. Again variable distribution from the farm irrigation system is suspected. In 1972 these plots will be irrigated with the small sprinkler system which will permit better control and distribution of water applied. The Influence of Water, Systemic Insecticides and Sidedress Nitrogen on the Incidence of Speckle Leaf M. L. Vitosh, R. W. Chase and A. L. Wells Departments of Crop and Soil Science and Entomology The speckle leaf disorder was of considerable economic concern in certain varieties and areas of the state in 1968 and 1969. As a consequence studies were performed in 1970 and 1971 to measure those factors which may contribute to the problem. Experiments on the Lennard Farm in Monroe County in 1970 revealed that excessive water and inadequate nitrogen at the early stages of growth on the Haig and Norchip varieties increased the occurrence of the speckle leaf lesions and reduced yields when compared to plots which received less water and did not show nitrogen deficiencies. To pursue this further a similar study was conducted in 1971 at the Montcalm Experimental Farm which in addition to water management and sidedress nitrogen levels also evaluated in interaction of systemic insecti- cides. Procedure Plots of the Haig variety were planted on April 29, 1971 at spacings of 34" between rows and 9 inches within the row. Plots were established using: no systemic insecticide; 3 lb/A phorate (Thimet) and 3 lb/A Disulfo­ ton (Disyston). Four sidedress nitrogen levels were compared on the sub plots: none; 75 lb/A; 150 lb/A; and three applications of 50 lb/A each. Plowdown fertilizer was 70-0-120. The planter fertilizer was 1250 lb/A 6-12-12. Duplicate plots were established so that one-half of the experiment could be given additional water early in the growing season. To these plots an additional 3 inches of water was added between June 10 and 14. This was done in an attempt to simulate conditions which occurred in 1968 and 1969 just prior to the reports of fields with high incidence of speckle leaf. The plots were harvested on September 2, 1971. Total yield, size dis­ tribution, specific gravity, incidence of speckle leaf lesions and chip acceptability were all determined. Results Table 1 summarizes the yield response observed under the different levels of water management. The increased yields due to the additional water suggests that under these conditions leaching of nitrogen was not a problem and a nitrogen deficiency did not exist. The additional water applied at this time was beneficial. In terms of sidedress nitrogen, maximum yield response was obtained at the 150 lb level where the additional water was applied. Other studies have shown that the Haig does have a high nitrogen requirement in early plant development. On the normal irrigation treatment response to side­ dress N was not apparent. The greatest response under these conditions occurred when the nitrogen application was divided into three applications of 50 lb each. It was further observed that a reduced yield occurred in the plots treated with phorate when compared with the untreated or the disulfoton plots. This occurred only where the additional water was applied. Statistical analysis of the data did not show this to be a significant difference. The trend however did occur at all nitrogen levels. Table 2 summarizes the specific gravity data. As was noted with yields, higher specific gravities occurred on plots receiving the additional water. There was a slight reduction in specific gravity of potatoes harvested from the plots treated with a systemic insecticide when compared to the untreated plots. Nitrogen had no appreciable effect on specific gravity. The incidence of speckle leaf symptoms was not serious in 1971. Evidence of the lesions was present, however, it could not be consistently related to any of the treatments. Table 1. The cwt/A of Haig potatoes grown at different levels of water management, sidedress nitrogen and systemic insecticides. Additional Irrigation Additional Irrigation Normal Irrigation Normal Irrigation Sidedress Nitrogen No Banded Insecticide 0 75 150 50-50-50 Ave. 429 470 487 479 466 Disulfoton Additional Irrigation Phorate Additional Irrigation Average No Banded Insecticide Disulfoton Normal Irrigation Phorate Normal Irrigation Average 458 454 490 468 467 386 415 457 449 427 424 446 478 465 453 375 358 367 384 371 366 398 382 403 387 363 359 387 392 375 368 372 379 393 378 Table 2. The specific gravity of Haig potatoes grown at different levels of water management, sidedress nitrogen and systemic insecticides. Additional Irrigation Additional Irrigation Normal Irrigation Normal Irrigation Sidedress Nitrogen No Banded Insecticide Disulfoton Additional Irrigation Phorate Additional Irrigation Average No Banded Insecticide Disulfoton Phorate Normal Irrigation Normal Irrigation Average 0 75 150 50-50-50 1.076 1.074 1.076 1.075 1.073 1.073 1.075 1.074 1.074 1.074 1.074 1.072 1.074 1.073 1.074 1.073 1.075 1.073 1.074 1.073 1.071 1.071 1.072 1.072 1.070 1.071 1.072 1.070 1.072 1.072 1.072 1.072 Average 1.075 1.074 1.074 1.074 1.073 1.072 1.071 1.072 Herbicides for Weed Control in Potatoes Donald Wyse, William F. Meggitt and Robert C. Bond Department of Crop and Soil Sciences Russet Burbank potatoes were planted May 12 on a McBride sandy loam (2.0% organic matter) and treated preemergence on May 22 and postemergence on June 14. The design of the experiment was a rando­ mized block with three replications. Rainfall was .67 inches within 10 days after application. The major weeds present were pigweed (Amaranthus retroflexus) and barnyardgrass (Echinochloa crusgalli). The plot was visually rated June 30. The preemergence herbicide treatments on the sandy loam soil all gave 80% or more control of the broadleaf weeds. The best overall preemergence treatments were linuron, 2 lb/A, oryzalin + linuron, 1 1/2 + 1 1/2 lb/A, chlorobromuron, 2 lb/A, alachlor + dinoseb, 2 + 4 1/2 lb/A and Bay 94337, 1/2 and 1 lb/A, all of which controlled 96- 100% of both the broadleaf and grass species. Bay 94337 as a split pre- emergence and postemergence treatment on the sandy loam soil at 3/4, 1/2 lb/A preemergence and 1/4, 1/2 lb/A postemergence also controlled 100% of the total weed population. Preemergence and Postemergence Weed Control Evaluations in Potatoes. Montcalm Co. 1971 Planted: May 12, 1971 Rated: June 30, 1971 Treated: Pre - May 22, 1971 Post- June 14, 1971 Weeds Present: pigweed, purslane, barnyardgrass, crabgrass Soil Type and Organic Matter: McBride sandy loam, 2.0% Trmt. No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 Preemergence Trmt. Lorox Patoran GA-2-270 GA-2-271 Ryzelan+DNBP Ryzelan+Lorox Maloran RP-17623 Lasso+DNBP Sencor Rate lb/A Preemergence Postemergence Postemergence Rate lb/A Trmt. Empty Table CellEmpty Table Cell 0.0 2 Empty Table CellEmpty Table Cell0.0 2 Empty Table CellEmpty Table Cell0.0 2 Empty Table CellEmpty Table Cell0.0 2 1 1/2+4 1/2 Empty Table CellEmpty Table Cell0.0 Empty Table CellEmpty Table Cell 0.0 1 1/2+1 1/2 Empty Table CellEmpty Table Cell0.0 2 Empty Table CellEmpty Table Cell3.3 1 1/2 2 +4 1/2 Empty Table CellEmpty Table Cell0.0 Empty Table CellEmpty Table Cell0.0 1/4 Empty Table CellEmpty Table Cell Sencor Sencor Sencor Sencor ------ 1/2 1 3/4 1/2 --- 0.0 Empty Table CellEmpty Table Cell0.0 0.3 0.0 1.3 Sencor Sencor Sencor 1/4 1/2 1 No treatment — No trmt. -- — 0 - no injury and no control; 10 - complete control or kill Weed Control Weed Control ing Rat Rating Injury Bd. Lv. Grass 10.0 10.0 10.0 10.0 8.0 10.0 10.0 9.6 10.0 10.0 10.0 10.0 10.0 10.0 10.0 — 10.0 6.6 8.6 6.6 9.3 10.0 9.6 9.0 10.0 8.6 9.6 10.0 10.0 10.0 10.0 — INSECTICIDE EVALUATION A.L. Wells, Department of Entomology The research on potato insects and nematodes at the Montcalm Experimental Farm was composed of three separate studies: (a) an evaluation of soil systemic insecticides alone or in combination with foliar applications; (b) a continuation of the study on the role of nematode control in cash crop rotations; and (c) a study to determine the varietal response of potatoes to in-row band applications of soil systemic insecticides on speckle leaf, maturity, yield and tuber quality. A corollary study on the evaluation of foliar insecticides for the control of foliar feeding insects; d) was conducted at the Muck Experimental Farm. A. Evaluation of Soil Systemic and Foliar Insecticides Procedure Seventeen treatments including eight soil systemic insecticides alone or in combination with additional sidedress or foliar applications were evaluated for foliar insect control and yield. Russet Burbank and Norchip seed planted in 12 inch spacings were used in the study. A normal fertilizer program of 200 lb. ammonium nitrate and 200 lb. 0-0-60 were plowed down and 800 lb. of 14-14-14 plus 2% Mg was banded at planting with 70 lb. of additional nitrogen side- dressed at hilling on June 23. The soil insecticides were either broadcast and disced in prior to planting, placed in a 4 inch band in the seed furrow prior to covering, sidedressed on each side of the row prior to hilling, or applied as foliar sprays. The plots consisted of three applications of four 50 foot rows (two rows of each variety). The broadcast and band applications were made and the plots planted on May 5 and Lorox was applied preemergence. The foliar applications were made on June 22, July 15 and 29. Potato flea beetle control was determined by counting the number of feeding holes in 10 leaves of each variety in each plot on June 22. Foliar insect populations were evaluated on July 7, 15, 29, August 9, 19 and 31 by taking ten sweeps with an insect net on each plot. The total insects collected from each treatment for the six samplings are presented in Table 1. The inside row of each variety was harvested on September 23 and yield and size distribution of the tubers determined. These data are presented in Table 2. Results All of the treatments applied at planting provided early season control of the flea beetles as shown by the feeding hole counts. High populations of the flea beetles as well as potato leafhoppers, and green peach aphids developed during the season on certain plots. Included in the high flea beetle counts were the emergence of new adults in late August. This may represent the start of a third generation on late varieties. The relatively low aphid populations in the untreated plots was the result of early maturing vines caused by heavy early flea beetle and leafhopper populations. The overall effectiveness of Table 1. The effects of soil systemic and foliar insecticides on insect populations. Material & Formulation Thimet 15% Gran Diazinon 4 EC + Sevin 50% WP + Cygon 10% Gran Am Cyan 92100 15% Gran Am Cyan 64,475 10% Gran Disyston 15% Gran Disyston 15% Gran + MSR 2 SC + Guthion 2 SC MSR 2 SC + Guthion 2 SC + Disyston 15% Gran Disyston 15% Gran + Disyston 15% Gran Disyston 6 SC Disyston 6 SC + Disyston 15% Gran DS-15647 10% Gran Furadan 10% Gran Furadan 10% Gran + Furadan 10% Gran Furadan 10% Gran Temik 10% Gran Untreated Untreated Placement Band Foliar Sidedress Band Band Band Band Foliar Foliar Sidedress Band Sidedress Broadcast Broadcast Sidedress Band Band Band Sidedress Band Band — — Lb Tox/A 3 lb 1/2 lb + 1 lb 1/2 lb + 1/2 lb 1/2 lb + 1/2 lb 3 lb 3 lb 3 lb 3 lb 3 lb 3 lb 3 lb 3 lb 4 lb 4 lb 2 lb 3 lb 3 lb 2 lb 2 lb 6 lb 3 lb — — Total insects collected Flea beetle Holes/leaf (June Total Insects Collected Flea beetle Holes/leaf (June 22) Norchi p 0.3 3.1 0.1 0.5 1.4 0.2 2.9 1.0 1.7 0.7 0.2 0.1 0.2 0.1 0 3.9 4.4 22) Burbank 0.1 5.5 0 1.1 0.7 0 4.5 0.7 2.3 1.5 0.4 0.4 0.3 0 0.1 2.7 4.1 Total Insects Collected Potato Flea Beetle 24 365 7 234 216 31 280 52 203 60 53 71 23 48 148 443 615 Total Total Total Total Insects Collected Tarnished Plant Bugs 36 44 23 56 92 41 73 58 104 40 21 52 47 34 12 124 133 Insects Collected Green Peach Aphids 716 897 801 1511 724 286 530 143 677 199 358 531 723 690 105 395 257 Insects Collected Potato Leafhopper 14 Insects Collected Aster Leafhopper 15 28 6 32 40 16 27 14 24 23 8 16 11 4 9 415 432 8 10 26 24 15 21 10 14 16 2 6 9 5 5 24 25 Total Insects Collected Parasites and Predators 22 14 16 20 28 18 18 11 8 15 17 22 18 23 11 20 28 * Broadcast—Liquids applied in water at 75 gal/A and disc incorporated; Band—Rates based on 34" rows (15,390 row-ft/A); Sidedress-Band on both sides of row June 22 prior to hilling; Foliar—Applied in water at 90 gal/A using drop nozzles with CO2 sprayer on June 22, July 15 and 29. Table 2. The effect of soil systemic and foliar insecticides on potato yield and size distribution. Russet Burbank Russet Burbank Russet Burbank Russet Burbank % Size Distribution Norchip Norchip % Size Norchip % Size Distribution Norchip % Yield Material & Formulation Thimet 15% Gran Diazinon 4 EC + Sevin 50% WP + Cygon 10% Gran Am Cyan 92100 15% Gran Am Cyan 64,475 10% Gran Disyston 15% Gran Disyston 15% Gran + MSR 2 SC + Guthion 2 SC MSR 2 SC + Guthion 2 SC + Disyston 15% Gran Disyston 15% Gran + Disyston 15% Gran Disyston 6 SC Disyston 6 SC + Disyston 15% Gran DS-15647 10% Gran Furadan 10% Gran Furadan 10% Gran + Furadan 10% Gran Furadan 10% Gran Temik 10% Gran Untreated Untreated Placement Band Foliar Sidedress Band Band Band Band Foliar Foliar Sidedress Band sidedress Broadcast Broadcast Sidedress Band Band Band Sidedress Band Band — — Russet Burbank Yield (cwt/A) 362 334 346 272 394 366 371 422 395 375 400 343 380 340 362 249 262 % Size Distribution Less than 1 7/8” 3% 4 3 4 3 3 4 2 4 4 4 4 3 4 4 5 5 % % Size Distribution 1 7/8” to 10 (cwt/A) oz. 64% 19% 14% 303 Size Distribution 10 oz. and over off type Size Distribution 1 7/8” Distribution Less to 3 than 1 1/4” 7/8” 9% 83% 3 1/4” and over 8% 57 54 54 61 58 57 54 60 57 57 59 59 57 59 67 71 21 20 14 16 22 20 27 18 19 23 18 21 19 19 12 12 18 23 28 20 17 19 17 18 20 16 19 17 20 18 16 12 289 374 266 313 335 319 363 383 350 371 348 350 313 347 227 246 8 5 6 6 7 8 6 8 7 6 7 7 10 6 13 10 87 86 86 85 85 87 84 83 88 86 87 85 81 86 84 89 5 9 8 9 8 5 10 9 5 8 6 8 9 8 3 1 the Amer. Cyan. 92100, DS-15647, Furadan and Temik as well as split applications of Disyston may lead to their commercial use in the future. The degree of insect control is reflected directly in the yield and size distribution. B. The Role of Nematode Control in Cash Crop Rotations i Purpose of Study To determine the effects of nematode control with soil fumigants and granular nematocides on five different three year rotations of cash crops. The study was initiated in April of 1968 and carried through a complete rotation and a follow-up evaluation in 1971. Although a high population of root leison nematode, Pratylenchus penetrans, was present during the first two years of the study, sampling in the spring of 1970 indicated the population had dropped to a very low level. The populations have not recovered as indicated by subsequent samplings in 1971. Procedure The soil treatments used in the study consisted of Annual Fumigation (FA)— Fumigated with Vorlex at 10 gallons per acre on October 25, 1969; Fumigation as needed (FN)—Fumigated with Telone at 20 gallons per acre on April 24, 1968; Granular nematocide (Bay)—Bay 68138 (Nemacur) granules incorporated on May 7, 1970 prior to planting at rate of 6 lbs. active per acre; and Untreated (Unt.)— no soil treatments applied. An adjacent area of alfalfa seeding was plowed in 1969 and fumigated with Vorlex (Vor) at 30 gallons per acre on October 25, 1969. These treated areas were crossed with four replications of five different rotations as given in Table 3. Normal agronomic practices were followed in all of the plots, including herbicides and systemic insecticides. Supplementary foliar insecticides and fungicides were applied on a 7-10 day schedule. The planting date, variety and harvest data are presented in Table 3. Results There were no apparent differences in vine growth in the different treatments early in the season however by late August the untreated plots had matured while the granular treated plot (Bay) as well as the Vorlex (Vor) and FA plots remained green. This difference in late growth is reflected in the yields and increased tuber size of these plots. The preceding crop had little apparent affect on these findings. The lower yields in the untreated plot may be from the lack of earlier treatments since the nematode populations present in 1971 could not account for these differences. NOTE: A complete summary of this study is being made and will be available later. C. Varietal Response to Soil Systemic Insecticides A study to compare the response of 12 varieties of potatoes to soil applications of systemic insecticides was continued after a preliminary study in 1970. The principal factor to be studied was the speckling condition to the lower leaves which had been observed in prior studies. Table 3. Agronomic and Yield Data from the Nematode Rotation Study. Variety: Russet Burbank "B” seed in 12 in. spacing. Fertilizer: 200 lb. Anmonium Nitrate plus 200 lb. 0-0-60 plowdown; 800 lb. of 14-14-14 + 2% Mg banded at planting; 70 lb Nitrogen sidedressed on June 15. Systemic Insecticide: Disyston 15% Gran. (3 lb. act/A) banded at planting Date Planted: May 11 Herbicide: Lorox applied pre-emergence May 26 Foliar Insecticide: Thiodan, Meta-Systox-R or Diazinon + Sevin applied with Date Vines Killed: September 30 Date Harvested: October 12 Date Specific Gravity Determined: October 21 fungicide on 7-10 day schedule. Soil Yield/A Yield/A Cwt Bu % Size Distribution l-7/8"-10 oz % Size distribution Treatment Plot 1 (Potatoes 1968, 1969, 1970) to 1-7/8" % Size Distribution Plot 1 (Potatoes 1968, 1969, 1970) Plot 1 (Potatoes 1968, 1969, 1970)Plot 1 (Potatoes 1968, 1969, 1970)Plot 1 (Potatoes 1968, 1969, 1970) Plot 1 (Potatoes 1968, 1969, 1970) Plot 1 (Potatoes 1968, 1969, 1970) 10 oz + % Size Distribution Off-type Plot 1 (Potatoes 1968, 1969, 1970) FA FN Unt Bay Vor 377 337 313 363 410 628 561 522 603 683 5% 5 7 4 4 65% 63 63 60 60 21% 17 13 17 27 9% 15 17 19 9 Plot 2 (Potatoes 1968, 1968, Beans 1970)Plot 2 (Potatoes 1968, 1968, Beans 1970) Plot 2 (Potatoes 1968, 1968, Beans 1970)Plot 2 (Potatoes 1968, 1968, Beans 1970) Plot 2 (Potatoes 1968, 1968, Beans 1970) Plot 2 (Potatoes 1968, 1968, Beans 1970) Plot 2 (Potatoes 1968, 1968, Beans 1970) 61% 62 61 58 64 Plot 3 (Beans 1968, Cucumbers 1969, Potatoes 1970) 346 363 297 334 347 FA FN Unt Bay Vor 5% 5 6 6 4 22% 19 16 24 22 12% 14 17 12 10 Plot 3 (Beans 1968, Cucumbers 1969, Potatoes 1970)Plot 3 (Beans 1968, Cucumbers 1969, Potatoes 1970)Plot 3 (Beans 1968, Cucumbers 1969, Potatoes 1970)Plot 3 (Beans 1968, Cucumbers 1969, Potatoes 1970) 7% 12 21 18 11 576 605 495 557 578 Plot 3 (Beans 1968, Cucumbers 1969, Potatoes 1970) 611 566 543 640 580 Plot 4 (Cucumbers 1968, Sweet Corn 1969, Potatoes 1970)Plot 4 (Cucumbers 1968, Sweet Corn 1969, Potatoes 1970)Plot 4 (Cucumbers 1968, Sweet Corn 1969, Potatoes 1970)Plot 4 (Cucumbers 1968, Sweet Corn 1969, Potatoes 1970) Plot 4 (Cucumbers 1968, Sweet Corn 1969, Potatoes 1970) 640 589 493 615 661 69% 60 62 51 66 28% 19 18 24 32 21% 15 13 27 23 5% 5 7 3 5 Plot 3 (Beans 1968, Cucumbers 1969, Potatoes 1970) 367 340 326 384 348 Plot 4 (Cucumbers 1968, Sweet Corn 1969, Potatoes 1970) 384 354 296 369 397 FA FN Unt Bay Vor 61% 64 55 54 53 Plot 4 (Cucumbers 1968, Sweet Corn 1969, Potatoes 1970) 4% 5 6 4 4 FA FN Unt Bay Vor Plot 5 (Sweet Corn 1968, Potatoes 1969, Beans 1970) Plot 5 (Sweet Corn 1968, Potatoes 1969, Beans 1970)Plot 5 (Sweet Corn 1968, Potatoes 1969, Beans 1970)Plot 5 (Sweet Corn 1968, Potatoes 1969, Beans 1970) Plot 5 (Sweet Corn 1968, Potatoes 1969, Beans 1970) FA FN Unt Bay Vor 375 327 310 366 345 626 546 517 610 575 4% 5 5 3 4 63% 66 61 54 58 5% 20 18 19 6 Plot 5 (Sweet Corn 1968, Potatoes 1969, Beans 1970)Plot 5 (Sweet Corn 1968, Potatoes 1969, Beans 1970) 10% 15 21 18 12 23% 14 13 25 26 Specific Gravity 1.080 1.078 1.077 1.075 1.076 Plot 2 (Potatoes 1968, 1968, Beans 1970) 1.080 1.078 1.076 1.078 1.078 Plot 3 (Beans 1968, Cucumbers 1969, Potatoes 1970) 1.079 1.078 1.077 1.078 1.077 Plot 4 (Cucumbers 1968, Sweet Corn 1969, Potatoes 1970) 1.081 1.078 1.078 1.077 1.078 Plot 5 (Sweet Corn 1968, Potatoes 1969, Beans 1970) 1.080 1.078 1.077 1.075 1.078 Procedure Sixteen seed pieces of each variety were planted in three replications of 16 row-feet each for each treatment. The insecticide granules were placed in a 4 inch band in the seed furrow prior to covering with soil on May 6. Normal agronomic practices of fertilization, herbicide usage, irrigation and foliar applications of insecticides and fungicides were followed on all of the plots. Speckle leaf ratings were made at the time of hilling and sidedressing. Maturity ratings of the vines based on amount of green foliage present were made on August 20. Yields and size distributions of the tubers were made at harvest on September 28. The data are presented in Table 4. Results The differences in the speckle leaf incidence between certain treatments was apparent at the time of sidedressing and hilling. This condition could possibly have been the result of a slight retardation of early growth by the in-row applications. The three pound rate of application was on the upper limit of use for all materials on this type of soil. It also verifies the suggestion that these materials be placed with the fertilizer band to avoid any affects on the young plants. The affects of the Thimet treatment on the plants evidentally carried through to maturity and resulted in reduced yields of most varieties. D. Evaluation of Foliar Insecticides on Foliar Insects Procedure Twenty foliar treatments including recommended and candidate insecticides were evaluated for the control of foliar feeding insects at the Muck Experimental Farm (Clinton Co.). The treatments were randomized in three replications of paired 18 foot rows using Sebago. The plots were planted on May 18 using whole seed and the insecticides were applied with a hydraulic sprayer with drop nozzles delivering 125 gallons per acre. Applications were made on July 1, 14, 23, August 14, 23, August 5, 9, 16, 27 and September 2. Ten sweeps were taken on each of the plots and the totals collected on all replications for the duration of the study are presented in Table 5. Yields and size distribution of the tubers were determined at harvest on October 4. The data are presented in Table 6. Results Heavy populations of leafhoppers, flea beetles and Colorado potato beetles developed early on the untreated plots and aphids started building up by early August. The selectivity of the treatments became apparent as soon as the populations developed. The fluctuations of these differences resulting from residual effects of the materials are not shown in the summary however the counts are the result of the populations as they developed. Most of the treatments were effective on the potato leafhopper but were not effective on the extremely high populations present at the time of sampling. This is a result of the residual effectiveness of the materials on the highly active beetles when evaluated in small plots. The relatively low populations of aphids and flea beetles in the untreated plots were probably caused by the poor condition of the plants after the potato beetle and leafhopper damage occurred. Disyston 15% Gran. at 21 lb. (3 lb. tox.)/Acre Disyston 15% Gran. at 21 lb. (3 lb. tox.)/Acre Disyston 15% Gran. at 21 lb. (3 lb. tox.)/Acre Disyston 15% Gran. at 21 lb. (3 lb. tox.)/Acre Disyston 15% Gran. at 21 lb. (3 lb. tox.)/Acre Furadan 110% Gran. at 30 lb. (3 lb. tox.)/Acre Furadan 110% Gran. at 30 lb. (3 lb. tox.)/Acre Furadan 110% Gran. at 30 lb. (3 lb. tox.)/Acre Furadan 110% Gran. at 30 lb. (3 lb. tox.)/Acre Table 4. Varietal response to soil systemic insecticides Maturity Rating** Thimet 15% Gran. at 21 lb. (3 lb. tox.)/Acre Thimet 15% Gran. at 21 lb. (3 lb. tox.)/Acre Speckle Rating* Thimet 15% Gran. at 21 lb. (3 lb. tox.)/Acre Variety Yield Data Cwt/A Yield Data, % Size Distribution, -1 7/8" 1 7/8"-3 1/4" Thimet 15% Gran. at 21 lb. (3 lb. tox.)/AcreThimet 15% Gran. at 21 lb. (3 lb. tox.)/Acre Thimet 15% Gran. at 21 lb. (3 lb. tox.)/AcreThimet 15% Gran. at 21 lb. (3 lb. tox.)/Acre Yield Data, % Size Distribution, Yield Data, % Size Distribution, +3 1/4" Haig Norland MSU-709 FL-96 Sebago R. Burbank Norgold Norchip Onaway Katahdin Kennebec Superior Haig Norland MSU-709 FL-96 Sebago R. Burbank Norgold Norchip Onaway Katahdin Kennebec Superior Untreated Haig Norland MSU-709 FL-96 Sebago R. Burbank Norgold Norchip Onaway Katahdin Kennebec Superior 1.7 1.7 3.0 3.0 2.3 1.7 2.0 1.7 3.0 2.7 2.7 2.7 3.3 5.0 2.3 3.0 1.0 1.7 4.0 2.7 4.3 2.3 3.0 4.7 225 258 347 297 366 363 244 379 292 285 302 232 9% 9 4 6 7 3 9 6 7 7 5 6 68% 81 56 75 70 48 74 65 65 62 74 81 Disyston 15% Gran. at 21 lb. (3 lb. tox.)/AcreDisyston 15% Gran. at 21 lb. (3 lb. tox.)/Acre Disyston 15% Gran. at 21 lb. (3 lb. tox.)/Acre 5% 6 4 12 6 4 10 4 4 7 4 5 2.0 1.0 2.0 1.3 2.3 1.7 1.3 1.3 1.3 1.3 1.7 2.0 3.3 4.7 2.7 2.7 1.0 1.3 4.0 2.7 3.0 2.3 3.0 3.7 281 337 363 326 339 356 240 416 351 327 385 331 63% 78 52 78 71 42 80 53 51 56 62 66 Furadan 110% Gran. at 30 lb. (3 lb. tox.)/AcreFuradan 110% Gran. at 30 lb. (3 lb. tox.)/AcreFuradan 110% Gran. at 30 lb. (3 lb. tox.)/Acre Furadan 110% Gran. at 30 lb. (3 lb. tox.)/Acre 5% 6 3 14 5 4 10 5 4 5 6 7 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.3 317 356 337 303 384 365 229 411 394 332 363 307 59% 85 55 78 76 54 77 58 56 65 65 71 UntreatedUntreatedUntreated 3.0 5.0 2.7 2.7 1.0 1.7 4.0 2.7 3.7 2.3 2.7 3.7 Untreated Untreated 3.3 4.7 2.3 2.7 1.0 1.7 4.3 3.0 4.0 2.7 2.7 3.7 1.0 1.0 1.0 1.0 1.0 1.3 1.0 1.0 1.0 1.0 1.0 1.0 Haig Norland MSU-709 FL-96 Sebago R. Burbank Norgold Norchip Onaway Katahdin Kennebec Superior *Speckle Leaf Rating: 1—None apparent to 4—Injury very apparent. **Maturity Rating: (Aug. 20) 1—Vines green to 5—Mature (vines dead). ***Indicating Burbank 10 oz. and over. 56% 78 47 78 69 53 81 66 58 66 60 73 5% 5 2 11 7 3 9 3 5 8 6 5 303 382 355 318 390 392 227 402 360 286 360 315 Off-type Yield Data, % Size Distribution, Thimet 15% Gran. at 21 lb. (3 lb. tox.)/Acre -- -- -- -- -- 32% -- -- -- -- -- -- 23% 11 40 19 23 17*** 17 29 28 31 21 13 32% 16 44 10 23 24 10 43 45 37 34 29 36% 9 42 8 19 22 13 37 40 30 29 22 Untreated 39% 17 51 11 24 28 10 31 37 26 34 22 -- -- -- -- -- 30% -- -- -- -- -- -- -- -- -- -- -- 20% -- -- -- -- -- -- -- -- -- -- -- 16% -- -- -- -- -- -- Untreated Table 5. SUMMARY OF FOLIAR INSECT CONTROL ON POTATOES Mich. State Univ. Muck Exptl. Farm (Total insects collected from plots July 2-September 2) Material and Formulation Cygon 267 Cygon 267 Am Cy 72,841 2 EC Am Cy 84,484 2 EC —Azodrin 3.2 EC Meto-Systox R 2 EC Disyston 6 EC Orthene 75% WP Monitor 6 S Lannate 90% WDL Fundal 4 EC Fisons NC-6897 80% WP Diazinon 4 EC Diazinon 4 EC + Sevin 50% WP Zolone 3 EC Mobil MC-4044 2 EC Sandoz 52139 2 EC Geigy GS-15171 4 EC Thiodan 2 EC Untreated Untreated Lbs Tox/A. 1/2 lb 1 lb 1 lb 1 lb 1/2 lb* 1/2 lb 1/2 lb 1 lb 1 lb 1/2 lb 1/2 lb 1 lb 1/2 lb 1/2 lb + 1 lb 1 lb 1 lb 1/2 lb 1 lb 3/4 lb — — Potato Leaf­ hopper Aster Leaf­ hopper Miridae (Plant Bugs) 159 177 211 231 142 147 98 166 216 225 224 331 273 275 296 335 513 344 547 599 18 10 15 32 10 20 14 11 10 7 14 16 16 18 24 18 32 20 23 20 70 64 76 98 87 95 72 83 105 104 98 106 111 122 109 114 101 101 201 203 Flea Beetles Colorado Potato Beetles 1,109 862 1,080 933 1,274 897 1,056 1,103 1,115 906 794 1,059 977 932 882 1,024 910 829 740 862 187 180 159 144 174 203 172 51 132 96 9 28 25 34 47 13 20 1 205 231 Aphids 166 309 375 356 201 210 37 85 232 519 2,974 668 644 177 238 163 133 133 206 141 *Am. Cy. 84,484 applied July 1, 14 & 23; Azodrin applied Aug. 8, 17 and 31. Parasites and Predators 18 30 34 24 30 32 16 23 25 25 25 18 20 20 25 29 30 16 29 22 Table 6. FOLIAR INSECTICIDE EVALUATION ON POTATOES YIELDS Material Formulation and Cygon 267 Cygon 267 Am Cy 72,841 2 EC Am Cy 84,484 2 EC —Azodrin 3.2 EC Meta-Systox R 2 EC Disyston 6 EC Orthene 75% WP Monitor 6 S Lannate 90% WDP Fundal 4 EC Fisons NC-6897 80% WP Diazinon 4 EC Diazinon 4 EC + Sevin 50% WP Zolone 3 EC Mobil MC-4044 2 EC Sandoz 52139 2 EC Geigy GS-15171 4 EC Thiodan 2 EC Untreated Untreated Yield/A Yield/A Bu Cwt 464 507 520 773 845 867 Lb Tox/A 1/2 lb 1 lb 1 lb 1 lb Percent Size Distribution Less than 1-7/8" Percent Size Distribution l-7/8" - 3-l/4" Percent Size Distribution Greater than 3-1/4" 3% 3 3 3 3 4 3 3 4 4 4 2 3 3 3 3 2 3 3 3 67% 65 68 67 59 67 65 61 63 67 75 66 68 61 67 64 75 55 69 68 30% 32 29 30 38 29 32 36 33 29 21 32 29 36 30 33 23 42 28 29 513 513 480 574 579 462 525 430 501 521 537 511 507 429 523 458 407 1/2 lb* 855 1/2 lb 855 1/2 lb 800 1 lb 957 1 lb 965 1/2 lb 770 1/2 lb 875 1 lb 717 835 1/2 lb 1/2 lb + 1 lb 868 1 lb 895 1 lb 852 845 1 lb 715 872 763 678 3/4 lb — — 1/2 lb *Am. Cy. 84,484 applied July 1, 14 & 23; Azodrin applied Aug. 8, 17 and 31. All but two of the treatments resulted in higher yields than the average of the two untreated plots. The yields and size distribution resulting from the NC-6897 and GS-15171 treatments could be the lack of control of aphids and potato leafhoppers, respectively. The unusually high yields in the untreated plots reflect the inherent plant growth and maturity despite heavy insect damage to the foliage. Green Manure Study H. L. Kohls and R. W. Chase Department of Crop and Soil Sciences Potatoes are usually grown in rotation with other crops. On farms where potatoes are the principal cash crop, rotational crops are selected to improve the soil, reduce disease and insect problems, and when possible, to provide some additional cash return. Procedure In 1970 a trial was initiated to evaluate a sudangrass hybrid, rye­ grass, and lupines as green manure crops preceding potatoes. Planting dates and seeding rates are given in Table 1. Nitrogen at 150 lb/A was applied May 18 to the ryegrass and sorghum-sudan plots. Plots were replicated 4 times. Grain and/or forage yields were obtained and calcula­ ted at 12% moisture. All crop residues were returned to the respective plots. In September of 1970 all plots were cut with a rotary mower. In April of 1971 the area was plowed and planted to Russet Burbank potatoes. The fertility program was 70 lb N and 120 lb K/A plowdown, 800 lb/A 14-14-14 + 2% Mg banded and 70 lbs N/A sidedress. Results Table 1 gives the yield data obtained from the green manure crop practices. The sudangrass yields were greater than normally expected. Two cuttings of sudangrass and ryegrass were made. The ryegrass con­ tinued to make considerable growth even after the frost had killed off the sudangrass and lupine regrowth. The ryegrass developed a very extensive and fibrous root system which was very apparent when the potato plots were established in 1971. The plow-plant tillage was used and the root system of the ryegrass was so extensive that the soil was quite soddy and did not allow for good planting conditions. This condition, although to a lesser degree, was still noticeable at harvest time. A crop such as this could be useful to improve soil textural conditions particularly where clods are a problem. Table 2 summarizes the potato yields. There is a slight trend to a greater yield on the plots which followed the lupines. There was no appreciable difference in terms of the size distribution. A second year of the trial is currently underway Table 1. Planting dates, seeding rates and yields of four green manure crops preceding potatoes. Empty table cell 1. sudangrass 2. ryegrass 3. lupines 4. lupines Seeding Rate lb/A 30 20 75 131 Seeding Grain Bu/A — Forage Tons/A Date May 30 5.96 May 9 — 2.95* May 9 0.99 1.34 May 9 32.95 44.74 Total Tonnage/A 5.96 2.95 2.42 2.80 *considerable growth after September 10 not harvested Table 2. The yields and quality of Russet Burbank potatoes following four green manure crops. Empty table cell 1. sudangrass 2. ryegrass 3. lupines-75 lb/A 4. lupines-131 lb/A Cwt/A 319 320 348 336 Percent Size Distribution -1 7/8 Percent Size Distribution Percent Size Distribution 1 7/8-10 oz. + 10 oz. 6.6 4.6 6.0 7.1 17.7 19.8 20.1 20.0 60.0 56.9 56.0 57.9 Off Type 15.7 18.7 17.9 15.0 Corn Hybrids, Plant Population and Irrigation Department of Crop and Soil Sciences E. C. Rossman Agronomic data for 56 commercial and experimental corn hybrids, irrigated and not irrigated in 1971, are presented in Table 2. Irrigated corn averaged 162.5 bushels per acre compared to 28.2 not irrigated, a difference of 134.3 bushels for irrigation. Rainfall was unusually low in 1971. Total amounts were: May = .93", June = 1.5", July = 1.22", August = 2.67", September = 4.0". Effective rainfall (.40" or more) during this period occurred on: June 13 = .51", July 5 = .40", August 11 = .80", August 23 = .38", August 25 = .60", September 6 = 2.08", September 20 = .58", and September 26 = .54". During June-August there were only five effective rains with a total of 2.69". Buoyoucous soil moisture blocks were placed at 6, 12, 18, and 24-inch depths in both unirrigated and irrigated plot areas. Soil moisture readings are presented in Table 1. Without irrigation, soil moisture at 12-24" depths remained below 50% water holding capacity from July 5 to August 30 when readings were discontinued. The range (highest and lowest) in yields for the 56 hybrids was: irrigated 210.5 to 91.0, not irrigated = 41.9 to 10.6. The highest yielding hybrid, Michigan Exp. 67-3124 (2x) produced 172.5 bushels (210.5 vs. 38.0) more when irrigated than when not irrigated. The lowest yielding hybrid, Renk NR1 (2x)— a very early maturing hybrid, yielded 80.4 bushels (91.0 vs. 10.6) more when irrigated. Hybrids significantly better than average in yield when irrigated in 1971 were (in order of early to late maturity): Acco UC2301 (2x), Michigan 396-3X (3x), Pioneer 3784 (2x), Mich. Exp. 67-2023 (2x), Pride R290 (2x), Blaney B-AA (2x) , Michigan 572-3X (3x), Super Crost S25 (2x), Michigan 500-2X (2x), Mich. Exp. 69-3097 (3x), Super Crost S27 (2x), Michigan 511-3X (3x), Blaney BX-AA (2x), P.A.G. SX69 (2x), Jacques JX162A (2x), Michigan 555-3X (3x), Funk Bros. G4444 (2x), Mich. Exp. 67-3124A, and Mich. Exp. 67-3124. Hybrids significantly better than average in yield when not irrigated in 1971 were (in order of early to late maturity): Funk Bros. G4180 (2x), Cowbell SX102 (2x), Funk Bros. G4263 (3x), Mich. Exp. 67-4006 (2x), Cowbell SX002 (2x), Michigan 380-3X (3x), Mich. Exp. 67-3106 (3x), Acco UC1900 (2x), Acco UC1901 (2x), DeKalb XL24 (2x), Blaney B-AA (2x), Mich. Exp. 69-3097 (3x), Jacques JX162A (2x), Michigan 555-3X (3x), Funk Bros. G4444 (2x), Mich. Exp. 67-3124A (2x), and Mich. Exp. 67-3124 (2x). Only seven of the 19 hybrids significantly better than average in yield irrigated were also significantly better than average without irrigation. The agreement of high yield selection from irrigated vs. not irrigated trials was less with the extreme drouth of 1971 than in three previous years, 1968-1970, when correlations were much higher and highly significant— .860 in 1968, .839 in 1969, and .927 in 1970 compared to a non-significant correlation of .182 in 1971. Four-Year Averages 1968-1971 Table 3 presents a four-year summary of yields and stalk lodging. Yields. Irrigated corn averaged 68.9 bushels more than unirrigated, 147.1 vs. 78.2, for the four-year period. The highest yielding hybrids averaged 92.5 Table 1. Per cent water holding capacity at 6, 12, 18, and 24-inch soil depths in unirrigated and irrigated plots, dates and amount of irrigation water applied 1971. Date of soil moisture reading Not irrigated 12" Not irrigated 6" Not irrigated 18" Not irrigated 24" irrigated 6" Irrigated 12" Irrigated 18" Date of irrigation 24" irrigated Inches of water applied June 22 June 29 July 5 July 14 July 20 July 27 August 2 August 10 August 17 August 24 August 30 Empty table cell Empty table cell Empty table cell 100 100 50 18 18 18 18 18 18 18 18 82 100 100 100 98 94 99 98 100 100 100 100 45 18 18 18 18 18 72 22 68 62 80 74 20 18 18 18 18 18 18 24 20 100 100 48 18 18 18 18 18 18 18 18 Empty table cell Empty table cell Empty table cell 86 100 98 100 96 92 98 98 100 100 100 90 100 85 90 90 90 96 98 99 99 100 80 100 85 72 64 84 92 98 99 95 100 Empty table cell Empty table cell Empty table cell June 23 June 27 July 3 July 7 July 12 July 16 July 20 July 23 July 27 August 2 August 6 Empty table cellAugust 13 Empty table cellAugust 17 Empty table cellTotal .75 1.00 1.00 .75 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 12.50 Empty table cell Empty table cell Empty table cell Empty table cell Empty table cell Empty table cell Empty table cell Empty table cell Empty table cell Empty table cell Empty table cell Empty table cell Empty table cell Empty table cell Empty table cell Table 2. Montcalm County Trial - Irrigated vs Not Irrigated NORTH CENTRAL MICHIGAN One, Two, and Three Year Averages - 1971, 1970, 1969 Zone 3 Hybrid Michigan 200 (4x) Renk NR1 (2x) Pride R200A (2x) Pride R221 (3x) Michigan 275-2X (2x) 2 Funk Bros. G4180 (2x) Michigan 250 (4x) Michigan 300 (4x) Michigan 280 (4x) 2 Cowbell SX102 (2x) 2 Funk Bros. G4263 (3x) 2 Mich.Exp. 67-4006 (2x) 2 Cowbell SX002 (2x) 2 Michigan 380-3X (3x) 2 Mich.Exp. 67-3106 (3x) 2 Acco UC1900 (2x) Northrup King PX20 (2x) Michigan 400 (4x) Acco UC2300 (2x) Pioneer 3911 (2x) % Moisture 1971 % Moisture % Moisture 2 yrs 3 yrs Bushels per acre 1971 Irrig. 1971 Not irrig. 23 23 23 23 23 104.4 33.3 91.0 123.6 30.0 136.5 147.5 114 20 21.4 20 10.6 — 21.9 — — 135 23 22.6 17.6 — 22.9 — — 29.7 144 23 23.2 23.2 — — 139.5 34.5 — 138 23.3 23 144 23.5 23 149 23.9 23 147 24.2 — 136.8 23.1 24.7 152.5 153.0 26.4 24 — 147.1 36.8 — 155.0 34.8 24.4 24.4 25 — 147.0 36.1 140 24.8 — — 140.0 34.1 — 24.8 24 — 141 142.4 167.1 41.4 — 25.0 — — — — 160.6 35.8 — 152 157.9 21.1 140 25.9 142.8 25.5 — 156.4 131 22.6 129.1 25.0 25.0 25.2 25 25.4 — 25.4 25 24 — 25 — 25 35.6 — — Mich.Exp. 67-4007 (2x) 1 Acco UC2301 (2x) Funk Bros. Exp. 23553 (2x) 25.6 — DeKalb XL15A (2x) 1 Michigan 396-3X (3x) 14.0 25.4 169 162.0 25.5 — — 178.6 19.1 — 28.0 — 156.1 25.6 — — 171.9 28.4 — 25.6 173 25 — 180.5 19.3 26 — Bushels per acre Bushels per acre Bushels per acre 2 Years 2 Years Bushels per acre 3 years 3 Years per acre Bushels Irrig. Not irrig. 62 % Stalk lodging dging % Stalk lo % Stalk lodging 2 years 2 Years 1971 % Stalk loding 1971 Not irrig. Irrig. Not irrig. 3 Years % Stalk lodging ars % stalk lodging 3 Ye Irrig. Not irrig. Not irrig. irrig. 115 — — — 146 — 134 — 149 — — — — — — — — 147 — 137 — — — — — 65 — — — 74 — 72 — 71 — — — — — — — 75 — 72 — — — — — — — 65 — 64 — 66 62 61 72 — 67 — 69 — — 68 64 — 62 63 — — — 70 Irrig. 13.3 23.4 15.2 2.2 5.7 10.3 12.9 4.9 7.1 6.7 4.6 3.8 1.6 11.7 1.5 4.5 2.2 10.8 12.8 6.0 6.5 7.9 6.8 6.9 6.5 0.8 0.0 — 0.0 0.8 — 0.8 9 11 5 2.2 3.0 2.2 2.3 0.0 — 11 5 7 5 — 0.7 0.0 0.8 — 2.3 0.0 3 10 — 0.0 0.8 0.0 1.5 — 0.0 2.3 0.8 — 0.0 — 0.0 0.8 — 4 6 3 3 — 4 — — — — — — — — 3 4 4 — — — 6 5 6 3 — — — — — — — 1 4 — — 1 2 2 1 — 1 6 — 5 9 — 5 — — — — — 5 5 — — — — — — — — — — — 8 — 12 10 — 10 — — — — — 4 9 — — — 1 Pioneer 3784 (2x) Super Crost SJ9 (2x) Blaney B-55A (3x) DeKalb XL306 (3x) Michigan 402-2X (2x) Mich. Exp. 66-2025 (2x) 2 Acco UC1901 (2x) 2 DeKalb XL24 (2x) Pioneer 3909 (2x) 1 Mich. Exp. 67-2023 (2x) Mich. Exp. 67-3110 (3x) 1 Pride R290 (2x) P.A.G. SX76 (2x) 1, 2 Blaney B-AA (2x) 1 Michigan 572-3X (3x) 1 Super Crost S25 (2x) 1 Michigan 500-2X (2x) 1 Mich. Exp. 67-1932 (2x) 1, 2 Mich. Bxp. 69-3097 (3x) Pioneer 3773 (2x) 1 Super Crost S27 (2x) 1 Michigan 511-3X (3x) 1 Blaney BX-AA (2x) Michigan 568-3X (3x) 1 P.A.G. SX69 (2x) 1, 2 Jacques JX162A (2x) 1, 2 Michigan 555-3X (3x) 1, 2 Funk Bros. G4444 (2x) 1, 2 Mich.Exp. 67-3124A (2x) 1, 2 Mich.Exp. 67-3124(2x) 25.8 -- 25.9 25 -- 26.0 26.0 25 26.0 25 26.2 26 -- 26.3 26.4 26 26.4 25 26.5 27 26 26.6 26 26.7 -- 26.7 26.8 25 26.9 -- -- 27.2 27 27.7 27.8 -- 27.9 -- 28.3 28 -- 28.4 28.5 -- -- 28.5 28.7 28 28.8 -- -- 28.8 29.0 28 -- 29.3 -- 29.4 29.6 -- - - 25 -- 26 25 26 -- 27 -- -- 26 -- -- -- -- -- 27 -- -- 28 -- -- -- 28 -- -- 28 -- -- -- -- 184.0 12.2 29.8 171.7 158.1 19.1 29.6 121.5 26.1 177.4 144.7 16.5 152.8 34.9 152.5 36.2 148.9 32.5 199.4 30.4 23.6 159.4 185.3 20.7 134.2 25.4 184.8 34.1 26.2 182.6 -- 16.6 27.9 188.9 184.0 186.7 32.0 -- 188.5 37.0 154.3 21.4 27.7 188.0 28.4 208.6 184.9 31.5 24.1 177.6 187.6 31.2 -- -- -- 185.4 34.5 181.3 41.9 195.3 35.2 191.7 36.2 210.5 38.0 -- -- -- -- -- -- 165 -- 136 161 161 -- 152 -- -- 173 -- -- -- -- 175 -- -- 169 -- 162 172 -- -- -- -- 74 -- 60 63 63 -- 73 67 79 74 70 -- 67 -- 77 -- -- 66 -- -- 67 -- 81 -- -- -- -- 30 -- 65 75 75 -- 78 -- -- 84 -- -- -- -- 83 -- 78 -- 79 -- 88 -- -- -- -- -- -- -- -- 170 -- 128 160 155 -- 154 154 197 170 182 -- 155 -- 176 -- 161 -- -- 164 171 -- -- -- -- -- -- 3.6 6.0 9.2 20.6 12.2 13.4 7.6 5.0 4.7 10.1 10.2 9.4 6.5 2.9 4.4 5.0 6.6 4.4 6.9 6.5 3.0 2.2 4.2 8.0 5.0 1.6 3.1 1.6 -- 3.1 1.6 0.8 0.0 -- 0.7 0.8 0.0 0.8 0.7 0.0 -- 2.3 0.8 -- -- 0.8 0.0 -- 3.1 0.0 -- 0.8 -- 0.8 0.0 0.0 0.8 0.0 -- -- -- 15.6 8.1 5.9 5.7 6.0 0.8 1.5 0.8 2.3 0.0 -- -- -- -- 5 15 7 8 4 4 5 6 6 3 4 5 -- 6 6 -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 2 6 2 3 3 3 0 2 1 3 1 2 -- 1 2 -- 3 10 7 6 3 -- -- 4 -- -- 3 3 -- 5 4 -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 5 12 10 8 6 -- -- 9 -- -- 5 6 -- 7 6 DeKalb XL45A (2X) Average Range 29.9 -- 26.1 25 21.4 to 29.9 20 to 28 -- 25 20 to 28 167.6 30.0 28.2 162.5 91.0 to 210.5 10.6 to 41.9 -- 154 114 to 197 Least significant difference 7 1 Significantly better than average yield, irrigated, 1971 2 Significantly better than average yield, not irrigated, 1971 0.8 0.6 0.5 15.2 5.8 -- 68 60 to 81 6 -- 153 114 to 175 5 -- 76 65 to 88 4 9.7 7.4 0.0 -- 0.9 -- -- -- 6 3 5 8 1.5 to 23.4 0.0 to 3.1 Empty table cell 2 to 15 Empty table cell 3 to 10 Empty table cellEmpty table cell 0 to 6 4 to 12 Empty table cellEmpty table cell Empty table cell Planted Harvested Soil type Previous crop Population Rows Fertilizer Soil test: Soil test: Soil test: Irrigation: 1971 May 6 Oct. 29 20,300 30" 160-140-140 6.0 pH P K 246 (high) 340 (very high) 12.5" 1970 May 8 Oct. 16 1969 May 3 Oct. 31 Montcalm sandy loam sorghum-sudan seeded to rye in fall Montcalm sandy loam sorghum-sudan seeded to rye in fall Montcalm sandy loam sorghum-sudan seeded to rye in fall 19,900 30" 213-160-160 6.3 246 (very high) 255 (high) 5.5" 19,500 30" 205-160-160 6.2 242 (very high) 237 (high) 6.0" Farm Cooperator: Theron Comden, Lakeview County Extension Director: James Crosby, Stanton Table 3. Average, highest, and lowest yields and per cent stalk lodging for corn hybrids irrigated and not irrigated for four years, 1968-1971. Average Average Not irrigated Highest Highest Not d irrigated No. of hybrids tested 56 64 63 56 Year 1971 1970 1969 1968 Irrigated 162.5 143.6 146.0 136.1 4 Year AverageEmpty table cell 147.1 % Stalk Lodging% Stalk Lodging% Stalk Lodging 1971 1970 1969 1968 56 64 63 56 7.4 5.8 2.9 1.1 4 Year AverageEmpty table cell 4.3 Irrigated 210.5 193.8 184.9 182.2 192.9 % Stalk Lodging% Stalk Lodging% Stalk Lodging 23.4 18.3 10.9 5.0 14.9 28.2 102.9 85.5 96.0 78.2 0.9 7.1 17.5 4.3 7.5 Lowest Lowest Irrigated Not irrigated 91.0 94.9 96.7 92.2 93.7 10.6 69.6 56.3 65.4 50.5 % Stalk Lodging % Stalk Lodging 1.5 0.0 0.0 0.0 0.4 0.0 0.0 5.6 0.0 1.4 41.9 127.7 108.6 123.2 100.4 3.1 24.4 57.8 13.9 24.8 Irrigation: 1971 = 12.5" June 23 = .75" June 27 = 1.0" July 3 = 1.0" July 7 = .75" July 12 = 1.0" July 16 = 1.0" July 23 = 1.0" July 27 = 1.0" Aug. 2 = 1.0" Aug. 6 = 1.0" Aug. 13== 1.0" Aug. 17 = 1.0" 1970 = 5.5" July 20 - 1" July 27 = 1” July 30 = .5" Aug. 4=1" Aug. 11 = 1" Aug. 13 = 1" 1969 = 6” July 26 = 1.5" Aug. 8 = 1.5" Aug. 14 = 1.5" Aug. 27 = 1.5" 1968 = 7.5" July 16 = 1.5" Aug. 2 = 1.5" Aug. 12 = 1.5" Aug. 20 = 1.5" Sept. 7 = 1.5" bushels more when irrigated (192.9 vs. 100.4) and the lowest yielding hybrids averaged 43.2 bushels more (93.7 vs. 50.5). Irrigation response of the highest yielding hybrids was more than twice as great as the response of the lowest yielding hybrids, 92.5 vs. 43.2 bushels increases from irrigation. Stalk lodging. The extreme drouth of 1971 had a reverse effect on stalk lodging compared to the previous three years. There was more stalk lodging with irrigation in 1971, 7.4% irrigated and 0.9% unirrigated. Lodging was greater on unirrigated plots in each of the three previous years. Plant Population x Irrigation Five hybrids at four plant populations irrigated and not irrigated were grown in each of four years 1968-1971. Yields and stalk lodging are summarized in Table 4. Yields. Populations of 15M and 19M were about equal in yield without irrigation in 1971—36.6 and 35.3 bushels per acre. Yields at 23M and 27M decreased to 20.2 and 10.5 bushels, respectively. In the three previous years without irrigation, the 19M population produced the highest yield when moisture stress was less. With irrigation in 1971, populations of 19M and 23M produced the highest yields (189.1 and 190.9) with lower average yields at 15M and 27M (172.9 and 180.6). In the three previous years, highest yields were attained at the 23M population with irrigation. In the four-year averages, highest yields were reached with a population of 19M without irrigation (16.4) and with a 23M population with irrigation (178.9). Stalk lodging. There was less stalk lodging without irrigation at all four populations than with irrigation in 1971. In the three previous years, the reverse had been true—more lodging without irrigation. Extreme drouth in 1971 drastically reduced plant size and there was a high percentage of barren plants without irrigation. Moisture content of grain at harvest. The effect of either irrigation or plant population on grain moisture was small during the four years. Irrigated corn averaged 0.8% higher moisture. Populations of 23M and 27M averaged about .7% higher moisture than populations of 15M and 19M. Table 4. Average yields and per cent stalk lodging at four plant populations irrigated and not irrigated for four years, 1968-1971. Irrigated Yields irrigated Yields Irrigated Yields Irrigated Yields irrigated Yields Irrigated Yields irrigated Yields 23,100 23,100 Not 27,200 27,200 Not 15,100 15,000 Not 19,200 19,200 Not irrigated Yields 172.9 122.2 125.5 143.5 141.0 36.6 91.0 90.7 113.9 82.8 189.1 144.1 157.5 169.3 165.0 35.3 111.7 108.5 130.2 96.4 190.9 158.2 173.2 193.1 178.9 20.2 93.4 95.7 107.0 79.1 180.6 151.2 147.8 178.4 164.5 10.5 85.1 86.3 89.4 67.8 % Stock Lodging% Stock Lodging% Stock Lodging % Stock Lodging% Stock Lodging % Stock Lodging% Stock Lodging% Stock Lodging 6.4 2.9 2.4 0.6 3.1 1.0 8.0 18.5 3.3 7.7 7.8 5.8 2.7 0.4 4.2 0.6 9.1 23.4 5.1 9.6 10.7 8.4 3.4 2.7 6.3 0.9 10.6 28.0 12.1 12.9 10.1 9.4 5.2 3.4 7.0 1.5 11.5 34.4 20.4 17.0 ar 71 70 69 68 erage % Stock Lodging 71 70 69 68 erage Yield Data and Summary Statement from the Miscellaneous Colored Bean Test M.W. Adams, A.W. Saettler and Jerry Taylor Departments of Crop and Soil Sciences and Plant Pathology This test included 16 entries, planted June 8-10 in 2-row plots per entry, with 4 replications, and in both 28" and 21" rows. Fertilizer of analysis 5-20-20 with 2% zinc and 2% manganese was applied in the row at planting time. Eptam was applied prior to planting, and irrigation water by sprinkler as needed after flowering. Due to planter difficulties (we aren't sure whether it was the planter shoe, or the problem of packing) only partial stands were obtained in the 21" rows. We have, therefore, data only for an insignificant number of entries at this row spacing. The yield data are given in the accompanying table. There was no blight of consequence this year. Strain Name or No. Yields in Pounds/A in 28" Rows (1) LRK 01 (halo resistant) 02 (halo resistant) (1) LRK 03(halo resistant) (1) LRK DRK 021 (halo resistant) 023 (halo resistant) DRK Manitou Light Red Redkote Light Red Charlevoix Dark Red Calif. Dark Red (2) Cranberry #026 (2) Cranberry #027 (2) Cranberry #028 Michigan Improved Cranberry (3) Commercial Yellow Eye Merithew Medium White Swedish Brown Bean *Figures in parentheses are yields in 21" rows. 1297.39 1465.57 1448.86 852.92 (1181.61)* 1264.49 1195.55 1102.05 (1324.50) 1230.02 1011.70 (1567.15) 1478.11 1532.95 1291.65 (1660.25) 1482.29 (1829.74) 1320.90 1301.05 (1379.60) 1320.90 (1150.35) Discussion 1) The first objective was to compare the yield performance of the halo­ blight resistant kidneys with the standards. In a year when blight was of trivial significance the yield data suggest that the experimental lines are equal to or perhaps slightly superior to the check varieties, excepting here DRK 021, which because of smaller seed size seems less promising than DRK 023. 2) The cranberry selections 026, 027, 028, are bush types with mosaic resistance, whereas Mich. Imp. is vine and susceptible to mosaic. There was no mosaic this year. The experimentals appear to be about equal in yield to the check, but they have the advantage that they do not lodge, whereas Mich. Imp. lodges badly every year. For this reason we are inclined to propose one of the bush lines for seed increase and distribution as a replacement variety of cranberry bean. 3) Among the three miscellaneous colored beans the Swedish Brown con­ tinues to perform very well. If market development is favorable for this bean in Sweden, there is no reason why we could not produce this variety profitably and safely in Michigan. 4) The few data from 21" rows suggest in the kidneys and cranberries particularly that closer row spacing, where water is available, or at least not limiting, would lead to higher yields. LUPINE RESEARCH H. L. Kohls Department of Crop and Soil Sciences Considerable progress has been made in lupine research this year in spite of two very unusual occurrences. 1. Most of the blue lupine, L. angustifolius, varieties produced very few flowers. One very early variety flowered normally and produced an excellent crop of seed, 35.37 bushels per acre. An adjacent variety pro­ duced no flowers. Other varieties produced a few flowers and little seed. Blue lupines require vernalization to initiate flower development. Temperature records show that late April, May and early June were much cooler than the corresponding dates a year ago when flowering was excell­ ent. Therefore high temperature was not the reason for poor flowering. The season was very dry and this may have had an influence on flower development. But we do not know the reason, at present, for the poor flowering. 2. White lupines, L. albus, grew normally and produced one cluster of flowers which produced mature seed. The plants then dried up and died without producing additional flowers. Observations showed a bad case of potato leaf hoppers, Empoasca fabae. The hoppers were controlled by spraying with carbaryl (Sevin) but too late to avoid severe loss of yield. The season was cool and dry and thin stands resulted in most areas. All planting was between April 20 and May 5. Preemergence chemical weed control was not as effective this year as in previous seasons and it appeared to be associated with the very dry soil. The data from the white lupine variety trial are shown in Table 1. There are 24 varieties and only four showed any alkaloids. About 2% of the seed in these four were bitter. The bitter seed can be eliminated this winter. Table 1. White lupine variety trial results - 1971. Variety Maturity Bu Per Acre Medium Medium Medium Medium Late Late Early Medium Early Medium Medium Early Early Late Medium Medium Medium Early Early Medium Early Medium Medium Early MSU-2 51-2 51-5 46-4 46-7 46-10 46-12 Gela X 243335 Selected for earliness MSU-4 47-1 47-4 47-5 47-8 Blanca from Georgia Blanca Selected for earliness Blanca 44-5 49-1 49-7 49-9 Gela 45-7 45-12 USSR-305 L. S. D. at 5% level C.V. = *2-3% bitter seed. 16.53 17.39 17.99 17.53 14.47 16.05 17.70 15.50* 17.27 19.48 16.63 22.12 13.91 15.44 15.75 17.23* 17.44 20.62 21.11 20.76 15.24* 18.44* 14.78 16.21 3.06 15.70 Also, we have two varieties not shown in Table 1 that are alkaloid free. This will be a total of 26 alkaloid free varieties available for use in various combinations to increase production of very high quality grain and forage varieties. Two group combinations appear much superior to MSU-2, now released to the Michigan Seed Foundation for seed increase. Table 2. A comparison of yields and stand between 14 and 7 inch rows. Average per acre Width of row Average per ace Total tons Roughage Per Acre Average Average per Acr e No. of Plants Bu of Grain 14" 7" Percent increase over 14" rows .94 1.21 .67 .87 8.92 11.25 81,185 161,576 28.72 29.85 26.12 99.02 Seeding rates of 75 and 150 lb per acre were used in the 14" and 7" rows, Table 2. The yields are low but increases of 26 to nearly 30 percent was made by doubling the seeding rate from 75 to 150 lb per acre. These data are very similar to the data of a year ago when the yields were much higher. In another trial seeding rates of 75, 100, 125, 150, and 175 lb per acre were sown in 6 replications, Table 3. Table 3. A comparison of stand and yield from various rates of seeding. Rate of seeding lb per acre Bu per acre 75 100 125 150 175 23.08 24.01 22.32 30.05 23.95 Plants per plot 180,048 230,868 233,772 296,208 310,728 It appears from the data that 150 lbs per acre may be the optimum rate of seeding even though higher rates give greater population. The non-flowering of blue lupines this year was unexpected. Nothing like this has been reported in literature, to our knowledge, from early sown seed. One variety, Unicrop, developed in Australia by Dr. Gladstones, flowered very early and produced an excellent crop of seed of 35.37 bushels per acre. This yield was on a small single plot for seed increase and points out the very high grain yield potential of this variety. It is very low in protein, about 25 percent where the range for the species is about 25-35 percent. Other early varieties produce fair to low seed yields but the remainder of the varieties produce very little or no seed. Dry soil seemed to be associated with non-flowering and earliness seemed to favor flower pro­ duction. The breeding of blue lupines for the production of early maturing, high yielding, low alkaloid, and non-shattering pods, has progressed satis­ factorily. The crosses are now in the F2 and F3 generations. A few F3 strains seem to be just what we are looking for but considerable work re­ mains to be done before any new variety is ready for release. SOIL FERTILITY RESEARCH ON DENT CORN, SWEET CORN, SOYBEANS, AND RED KIDNEY BEANS M. L. Vitosh Department of Crop and Soil Sciences In addition to the five soil fertility experiments on potatoes, seven additional were conducted in 1971. All but one of these experiments were in the potato rotation and all plots were irrigated. Soybeans were grown in place of red kidney beans in the N carrier and N rate and time experiments. This was the first attempt to grow soybeans in this area with irrigation. Source, Rate, and Time of Nitrogen Application on Field Corn: This experiment involved comparisons of broadcast versus sidedress N applications and urea versus sulfur-coated urea (SCU), a slow release N material. Two hybrids (Michigan 500-2x and Michigan 396-3x) were used. The soil at planting time was quite dry and less than 1.4 inches of rain fell during the next four weeks. The largest rain was .29 inches. Certain treatments suffered from fertilizer salt injury. Stand counts were made on three rows of all plots and varieties. The averages of plant population for three rows are shown in Table 1. Injury on one row was more noticeable than the other two. Fertilizer placement for this row was found to be closer than the recommended 1 1/2 inches to the side and 1 inch below the seed. One row was selected for harvest and thinned to 18,464 plants per acre. Although the average for the three rows for certain treatments was below 18,464 plants per acre, the row which was thinned, in all cases had plant populations of 18,464 plants per acre or greater. Plant population decreased quite drastically with increasing rates of broadcast nitrogen. The additional banded N on these treatments created a very critical situation during this dry weather period. In order to maintain the plant population and reduce salt injury, irrigation was started immediately after stand counts were made. Even though it was a very dry season, excellent yields were obtained with 5.7 inches of irrigation water. The best yield was 180 bu/A obtained with Michigan 500-2x and 240 lb N/A. Sidedress N again appears to be slightly better than broadcast N. Sulfur-coated urea did not increase the efficiency of nitrogen use above that of comparable treatments. Yields were similar where equal rates of N were applied. Leaf samples were taken from the leaf opposite the ear at initial silking. Samples were obtained from Michigan 396-3x but not Michigan 500-2x. Nitrogen content increased with the first few increments of N fertilizer. Although the values were not significantly different, samples from the two SCU plots were slightly lower. All values, including the 2.9% N value for the no N treatments are considered to be in the sufficiency range. Potassium-Magnesium Study with Field Corn: This experiment involved various rates of K fertilizer with and without Mg at two plant populations. Stand counts were made three weeks after emergence. It was obvious that increasing rates of broadcast potassium resulted in decreased plant population (Table 2). One row was more severely affected than the other two rows because of improper fertilizer placement. One good row, however, was selected from the low and high plant population levels and thinned to 15,290 or 18,646 plants per acre, respectively. Irriga­ tion water was immediately applied following the stand counts to reduce salt injury. Although the amounts of fertilizer applied in the band were not excessive, considerable injury was observed. Proper placement appears to be especially important on sandy soils in dry years. Likewise, large broadcast applications of N and K plowed down prior to planting may also cause considerable salt injury if soil moisture is in short supply. Yields were increased with the first 50 pounds of banded K2O/A (Table 3). Increases beyond this level were not significant at low plant population. However, two treatments with more than 50 lb K2O/A produced significantly better yields at the high plant population level. Yields beyond the 100 lb K2O/A level were not significant. Leaf analysis shown in Table 3 indicates that zinc was the only element significantly affected by the K-Mg treatments. Several trends, however, are present. As the K content of leaf tissue increases, Ca and Mg content de­ creases. Similar observations have been observed with potatoes. Zinc appears to have been increased by the highest rate of K (Treatment No. 6). Potassium-Magnesium Study With Sweet Corn: The K-Mg treatments had no affect on yields in 1971 (Table 4). The two-year average (1970-1971) indicates a slight yield response to 20 lbs K2O/A. Twenty pounds of K2O/A with Mg appears to be slightly better than the same rate of K without Mg. However, the average overall Mg treatments represents only a 2 cwt/A increase over the average of comparable treat­ ments. Nitrogen Carrier Study With Sweet Corn and Soybeans: No significant yield increases were obtained for these experiments in 1971 (Tables 5 and 6). A four-year average for sweet corn tends to favor urea and anhydrous ammonia. Calcium nitrate continues to result in the lowest yields. These same trends have been observed with potatoes. Residual Nitrogen Study With Soybeans: The plots in this experiment received no N in 1971. The objective was to evaluate any residual or carry-over N from the treatments on potatoes in 1970. Results of this experiment (Table 7) indicate no residual effect from the N treatment applied in 1970. Soybeans in the N carrier study out-yielded this experiment by 6-8 bushels. Similar results have been observed in 1968, 1969, and 1970, with red kidney beans. Nitrogen response with beans has not been uncommon in this part of Michigan. Nitrogen fixing bacteria cannot supply all the N needed by the beans. Zinc-Phosphorus Study With Red Kidney Beans: In 1969, a significant reduction in yields of red kidney beans was observed with 5 pounds Zn per acre banded annually for three years. A posi­ tive response at this location has not been observed on potatoes, sweet corn, or red kidney beans since 1967. The question of zinc toxicity became appar­ ent in 1970. These experiments have been continued with the intent of further evaluating zinc toxicity. In 1970, a different treatment (50 lbs of broadcast Zn applied in 1967) caused a significant yield reduction of pea beans. The results of this experiment are shown in Table 8. Although the yields were not significantly different, the no zinc treatment gave highest yields. The lowest yields were obtained at the low P level where zinc was broadcast in 1968. The four-year average (1968-1971) indicates a 2-3 bushel decrease with zinc treatments. Zinc content of whole plant samples show the increase in zinc con­ tent with the various zinc materials. Three annual applications of 5 pounds of Zn/A as zinc sulfate gave the highest concentration of zinc in plant tissues. Phosphorus levels had little effect on the concentration of zinc in plants. The application of zinc on acid sandy soils without regard to a zinc soil test is not recommended. Table 1. Effect of rate, source and time of nitrogen application on yield, percent N in leaf tissue and plant population of two irrigated corn hybrids. Nitrogen Application (a) lication (a) Nitrogen App Nitrogen Application (a) Nitrogen Application (a) Mich. 500-2x Mich. 500-2x Broad­ cast lb N/A Band­ ed Side­ dressed Total N lb N/A Yield (Bu/A) lb N/A lb N/A Plant Population (b) (Plants/A ) Mich. 396-3x Mich. 396-3x Plant Population (b) (Plants/Acre) Average Effects Average Effects Plant Population (b) (Plants/A ) Leaf Mich. 396-3x Anal- Yield ysis (Bu/A) (% N) Yield (Bu/A) 77 124 151 167 173 161 158 158 165 173 --- 13 11 23,058 22,779 21,038 19,485 19,764 21,380 20,386 19,454 20,138 19,578 --- 2.9 3.4 3.8 3.5 3.7 3.7 3.7 3.7 3.7 3.2 NS --- --- 94 133 155 167 169 161 161 163 173 166 10 --- --- 1,569 --- --- 22,862 22,748 20,339 18,863 18,381 20,090 19,640 18,863 19,457 19,019 1,300 --- 0 60 SCU 0 0 60 U 120 U 180 U 60 SCU 0 0 0 60 U 60 U 60 U 60 U 60 U 60 U 60 U 0 0 0 0 0 0 60 U 120 U 180 U 0 60 U 120 SCU --- Empty table cellEmpty table cell LSD (.05) treatments LSD (.05) treatments within varieties Empty table cell Empty table cell Empty table cell Empty table cell Empty table cell LSD (.05) varieties within treatments Empty table cell 0 60 120 180 240 120 120 180 240 180 --- 22,686 22,717 19,640 18,242 16,999 18,801 18,895 18,273 18,957 18,460 --- 1,444 111 142 160 167 164 160 165 168 180 159 13 11 --- (a)Broadcast urea (U) and sulfur-coated urea (SCU) was applied and plowed down one day before planting. Banded urea was applied at planting time 1 1/2 inches to side and 1 inch below the seed. Sidedressed urea was topdressed June 21, 1971. (b)Plant population 3 weeks after emergence before thinning to 18,646 plants per acre. Planted: May 4, 1971. Harvested: October 26, 1971 Plant Population: 18,646. Row Spacing: 28 inches Basic Fertilizer: 0-50-100 banded at planting time. Irrigation: 5.7 inches. Harvest Area: 116 sq. ft. Soil Tests: pH = 6.7, P = 186, K = 274 Previous crop: Red kidney beans Potassium-Magnesium Applications (a) Potassium-Magnesium Applications (a) Potassium-Magnesium Applications (a) Broad­ cast Band­ ed lb K2O/A K2O/A Broad­ cast lb Mg/A 0 0 50 100 150 250 0 50 150 250 0 50 50 50 50 50 50 50 50 50 0 0 0 0 0 0 50 50 50 50 0 50 100 150 200 300 50 100 200 124 148 146 143 147 158 136 147 160 LSD (.05) treatments LSD (.05) treatments within plant population empty table cellempty table cell empty table cell empty table cell empty table cell empty table cell LSD (.05) plant populations within treatment empty table cell 300 154 empty table cell --- empty table cell 15 --- 17,496 14,824 15,227 14,016 14,233 13,922 14,917 14,886 13,886 14,171 --- 1,025 131 158 158 172 165 159 156 165 169 173 --- 15 20,884 20,448 21,039 20,759 20,107 19,734 20,821 19,516 20,542 20,169 --- 1,589 128 153 152 158 156 159 146 156 164 164 11 -- 19,190 17,636 18,133 17,388 17,170 16,828 17,869 17,201 17,214 17,160 1,000 --- Table 2. Effect of potassium and magnesium on yield and plant population of 500-2X corn hybrid under irrigation. 15,290 Potassium-Magnesium Applications (a) Total K2O 15,290Yield (Bu/A) Plant population before thinning (b) 18,646Yield (Bu/A) 18,646 Plant population before thinning (b) Yield (Bu/A) Average Effects Average Effects Plant population before thinning (b) --- (a) Broadcast potassium and magnesium were applied and plowed down 5 days prior to planting. Banded potassium was applied 1 1/2 inches to side and 1 inch below seed at planting time. Potassium and magnesium sources were KCl and MgSO4. 14 14 --- -- (b) Plant population 3 weeks after emergence before thinning to 15,280 and 18,646 plants per acre. Planting: May 4, 1971 Row Spacing: 28 inches Basic Fertilizer: 50-50-0 banded, 180 N sidedressed June 21, 1971 Irrigation: 5.7 inches Previous crop: Potatoes Harvest: October 29, 1971 Harvest area: 116 sq. ft. Soil test: pH - 6.9, P = 205, K range = 104-220, Mg = 200 Table 3. Effect of rate of potassium and magnesium on elemental compo­ sition of corn leaves for Michigan 500-2X (18,646 Plants/A) Trt. #(a) N % Element Element P % Element Element Ca % Mg % Element K % Element Zn ppm Element Mn ppm Element Cu ppm 1 2 3 4 5 6 7 8 9 10 Not Determined Not Determined Not Determined Not Determined Not Determined Not Determined Not Determined Not Determined Not Determined Not Determined .27 .27 .27 .27 .26 .28 .28 .27 .25 .27 1.26 1.46 1.14 1.40 1.58 1.62 1.45 1.57 1.53 1.51 .94 .84 .84 .76 .68 .73 .79 .74 .72 .71 .65 .49 .60 .42 .31 .36 .50 .40 .38 .41 LSD (0.5)Empty table cell NS NS NS NS 36 34 32 31 37 51 37 39 43 34 11 80 76 62 70 81 81 94 88 102 63 NS 20 21 21 20 20 21 20 20 19 20 NS (a) Treatments are the same as the previous table. (b) Other elements which were not significantly affected by the treatments in this experiment: Fe, B and Al. Table 4. Effect of potassium and magnesium on yield of irrigated sweet corn. Potassium-Magnesium Applications (a) Potassium-Magnesium Applications (a) Potassium-Magnesium Applications (a) Potassium-Magnesium Applications (a) Broad­ cast Band­ ed lb K2O/A lb K2O/A Broad­ cast lb Mg/A Total k2o Sweet Corn Yield (cwt/A) Sweet Corn Yield (cwt/A) Sweet Corn Yield (cwt/A) 1971 1970-71 Average 0 0 0 0 0 120 0 0 0 0 0 20 40 60 80 40 20 40 60 80 0 0 0 0 0 0 50 50 50 50 0 20 40 60 80 160 20 40 60 80 80 89 92 94 86 94 101 99 90 83 Empty table cell Empty table cellEmpty table cell LSD (.05) NS Empty table cell Empty table cell Empty table cell Empty table cell Empty table cell Empty table cell Empty table cell Empty table cell Empty table cell Empty table cell Empty table cell 116 122 128 124 119 122 132 126 121 118 --- (a) Banded potassium was placed 1 1/2 inches to side and 1 inch below seed at planting. Broadcast potassium and magnesium were applied and plowed down prior to planting. Potassium and magnesium sources were KCl and MgSO4. Planted: May 27, 1971 Row Spacing: 28 inches Basic Fertilizer: 60-50-0 banded, 120 lb N/A sidedressed June 21, 1971 Harvest Area: 233 sq. ft. Soil Tests: pH = 6.6, P = 155, K = 220 Harvested: August 10, 1971 Plant Population: 18,000 Irrigation: 4.5 inches Previous Crop: Corn Table 5. Effect of source of nitrogen on yield of irrigated sweet corn. Source of Nitrogen Sweet Corn Yield (cwt/A) Sweet Corn Yield (cwt/A) 1971 1968-71 Average Ammonium Sulfate (a) Ammonium Nitrate (a) Calcium Nitrate (a) Urea (a) Anhydrous Ammonia (b) LSD (.05) 105 111 102 111 114 NS 116 115 110 121 124 -- (a) (b) 140 lb N/A topdressed May 18, 1971 140 lb N/A sidedressed May 18, 1971 Planted: May 27, 1971 Row Spacing: 28 inches Harvest Area: 233 sq. ft. Basic Fertilizer: 10-50-100 banded at planting time Soil Tests: pH = 6.5, P = 201, K = 265 Harvested: August 10, 1971 Plant Population: 18,000 Irrigation: 4.5 inches Previous Crop: Red kidney beans Table 6. Effect of source of nitrogen on yield of irrigated soybeans. Source of Nitrogen (a) Yield (Bu/A) Ammonium Sulfate Ammonium Nitrate Calcium Nitrate Urea Anhydrous Ammonia LSD (.05) 26 26 27 27 29 NS (a) 60 lbs N/A applied 10 days prior to plowing and planting Planted: May 27, 1971 Row Spacing: 28 inches Harvest Area: 349 sq. ft. Basic Fertilizer: 0-50-50 banded at planting time Harvested: October 20, 1971 Seeding rate: 60 lb/A Irrigation: 3.9 inches Previous crop: Potatoes Table 7. Effects of residual nitrogen on yield of irrigated soybeans. lb N/A (a) Yield (Bu/A) 0 120 180 240 300 LSD (.05) Treatments (a) Applied as urea in 1970 20 21 21 23 20 NS Planted: May 27, 1971 Row Spacing: 28 inches Harvest Area: 349 sq. ft. Basic Fertilizer: 0-50-50 banded at planting time Soil Tests: pH=7.0, P=216, K=162 Harvested: October 20, 1971 Seeding Rate: 60 lb/A Irrigation: 3.9 inches Previous crop: potatoes Table 8. Effect of zinc on yield and Zn content of plant tissue of irrigated kidney beans at two phosphorus levels. Treatment (lb Zn/A) None 25 lb (Zn SO4) (c) 50 lb (AZCo C100) (c) 5 lb (AZCo 12) (d) 5 lb (Zn SO4) (d) P Level (average) LSD (.05) Treatments Low P (a) Low P (a) High P (b) High P (b) Average Effects Effects Average (cwt/A) (PPM Zn) (cwt/A) (PPM Zn) (cwt/A) (PPM Zn) 43 36 36 41 40 39 -- 31 37 39 49 51 41 -- 44 44 44 42 42 43 -- 29 36 49 38 53 41 -- 43 40 40 42 41 -- NS 30 36 40 43 52 -- 7 LSD (.05) P Levels, Yield = NS, PPM Zn = NS LSD (.05) P Levels, Yield = NS, PPM Zn = NS LSD (.05) P Levels, Yield = NS, PPM Zn = NS LSD (.05) P Levels, Yield = NS, PPM Zn = NS LSD (.05) P Levels, Yield = NS, PPM Zn = NS LSD (.05) P Levels, Yield = NS, PPM Zn = NS LSD (.05) P Levels, Yield = NS, PPM Zn = NS LSD (.05) Treatments within P Levels LSD (.05) P Levels within Treatments NS NS 10 5 NS NS 10 5 -- -- -- -- (a) Low P = 22 lb P/A banded 1971. (b) High P = 300 lb P/A broadcast 1968 and 1971 + 22 lb P/A banded 1968, 69 & 71 (c) Zinc broadcast in 1968. (d) Banded annually 1968, 69 and 71. Planted: June 4, 1971 Harvest Area: 233 sq. ft. Plant Spacing: 4 inches Previous Crop: Red clover Soil Test: pH = 6.5, P range = 437 to 305, K = 220, Zn range = 3.0 to 12.9 Harvested: Sept. 17, 1971 Row Spacing: 28 inches Irrigation: Basic Fertilizer: 50-50-50 Preplant Incorporated and Preemergence Herbicide Combinations for Weed Control in Navy Beans Donald Wyse, William F. Meggitt and Robert C. Bond Department of Crop and Soil Sciences Gratiot navy beans were planted and treated June 14 on a McBride sandy loam (2.0% organic matter). The design of the experiment was a randomized block with three replications. Rainfall was .89 inches within 10 days after application and planting. The weeds present were lambsquarter (Chenopodium album), pigweed (Amaranthus retroflexus) and barnyardgrass (Echinochloa crusgalli). The plots were visually rated July 15. Two herbicides, EPTC, 2 lb/A and trifluralin, l/2 1b/A, were preplant incorporated, then chloromben, 2 lb/A, fluorodifen, 3 lb/A, dinoseb + chloramben (2:1) 1 gal/A and dinoseb, 3 lb/A, were applied preemergence in combination with the preplant treatments. EPTC, 2 lb/A, in combination with the preemergence treatments controlled 96- 100% of the total weed population, with the exception of chloramben, 2 lb/A, which controlled 73% of the ragweed population. Trifluralin, 1/2 lb/A, in combination with the preemergence treatments did not give more than 73% control of any of the three weed species. The preemergence treatments when applied alone did not give com­ plete control of the two broadleaf species and no control of barnyardgrass. Under these soil and weather conditions it was possible to obtain increased weed control at lower herbicide rates with preplant-preemergence combinations. Preplant Incorporated and Preemergence Weed Control Evaluations in Navy Beans. Montcalm Co., 1971. Planted: June 14, 1971 July 15, 1971 Rated: Treated: June 14, 1971 Weeds Present: pigweed, lambsquarter, barnyardgrass Soil Type and Organic Matter: McBride sandy loam, 1.5% Trmt. No. Preplant Inc. Trmt, Preplant Inc. Rate lb/A Preemergenc Preemergence Rate lb/A e Trmt. Empty table cellEmpty table cell Injury 1 2 3 4 5 6 7 8 9a 10a 11a 12a 9b 10b 11b 12b 2 1/3 Eptam 3 0.0 3/4 Empty table cellEmpty table cell0.0 Treflan Eptam+Treflan 2+1/2 Empty table cellEmpty table cell0.0 Empty table cellEmpty table cell0.0 Lasso Empty table cellEmpty table cell0.0 USB-3584 Empty table cellEmpty table cell 2/3 0.0 1 1/3 Empty table cellEmpty table cell2.3 Empty table cellEmpty table cell0.0 --- 2 Amiben 0.0 2 Preforan 0.0 2 Dynoram 1 gal 0.0 2 DNBP 0.0 USB-3584 USB-3584 No treatment Eptam Eptam Eptam Eptam 2 3 3 Treflan Treflan Treflan Treflan 1/2 Amiben 1/2 1/2 1/2 Preforan Dynoram 1 gal DNBP 2 3 3 0.0 0.0 0.0 0.0 Weed Control Rating Weed Control Rating Pigweed Lambsquarter Weed Control Rating Barnyard- grass 9.3 5.3 9.3 9.6 3.0 6.6 7.0 0.0 7.3 10.0 10.0 9.6 5.0 9.0 6.3 5.3 9.6 9.3 10.0 9.0 9.0 9.3 10.0 0.0 10.0 10.0 10.0 10.0 6.3 1.3 7.3 7.3 10.0 4.6 10.0 7.3 1.0 7.3 7.6 0.0 10.0 10.0 10.0 10.0 3.3 3.0 1.6 0.0 Preemergence Preemergence Preplant Inc. Rate lb/A Trmt. Rate lb/A Weed Control Rating Pig­ weed Weed Control Rating Lambs - quarter Weed Control Rating Barnyard­ grass Injury Continued. --- Trmt. No. Preplant Inc. Trmt. 9c 10c 11c 12c 13 14 15 No trmt. No trmt. No trmt. No trmt. ----- ----- ----- --- --- --- --- --- --- 2 3 1 gal 3 Amiben Preforan Dynoram DNBP Preforan+Lasso 2+1 1/2 Lasso+Amiben Eptam+1 1E 0.0 0.0 0.0 0.0 0.0 1 1/2+1 1/2 0.0 3+1 gal 0.0 0.6 7.0 2.6 2.3 10.0 4.6 0.0 1.6 0.0 10.0 10.0 0.0 0.0 0.0 1.0 0.0 0.0 0.0 2.0 3.6 0.0 0 - no injury and no control; 10 - complete control or kill