EARLY RESPONSE OFFLANTED _ , 7 BLACK WALNUT TO SITE MODIFICATION 1],; :. _ :.,..J_;Iv_~;j::- Thesis for the Degree Of Ph D MICHIGAN STATE UNIVERSITY GHAUS MOHAMMED KHATTAK 1968 ’ nasxs Lib‘KIIRY IIIIIIIILIIIIIJQIIIIILIIIIIIIIILIQIIIIIIHLIIIIIIIIIHII j. Mgfgéjsfgtc This is to certify that the thesis entitled EARLY RESPONSE OF PLANTED BLACK WALNUT T0 SITE MODIFICATION presented by Ghaus Mohammed Khattak has been accepted towards fulfillment of the requirements for M degree in %fl 444$ Major professor Forestry Date August 12, 1968 0-169 ABSTRACT EARLY RESPONSE OF PLANTED BLACK WALNUT TO SITE MODIFICATION by Ghaus Mohammed Khattak The effects of wind protection, mulching, irrigation, and fertilizer application were investigated during 1967 and 1968 on the early growth of field planted black walnut. The growth criteria used for assessing plant response were leaf area, height, and diameter. Foliar analyses were employed to indicate the nutritional status of the plants. Soil moisture was measured by neutron thermalization in 1967 and gypsum blocks in 1968. Snow fencing provided wind protection and fresh hard— wood chips, mulch. Fertilizer was applied in perforated plastic sacks. Irrigation comprised weekly surface applica- tion of 7.5 liters of water to each tree unless at least 2.5 cms. of natural precipitation had been received during the previous week. Mulching as well as irrigation, separately maintained the 0-30 cms. soil layer at a significantly higher moisture content as compared to the control. None of the treatments applied had any effect on the soil moisture content at the 30-60 cms. depth. During the first growing season (1967), mulching in— creased soil K at 15 cms.depth, and irrigation decreased it. Ghaus Mohammed Khattak Irrigation increased foliar K from a level indicating de- ficiency to that characteristic of an intermediate level of nutrition. Fertilizer application increased foliar N but not sufficiently to bring the plants from the intermediate to the normal level of nutrition. Mulching increased leaf area. The response was greatest when wind protection and mulching were combined -- the two treatments together in- creasing leaf area by 70 per cent. By the middle of the second growing season (July, 1968) mulching had increased foliar K concentration by 100 per cent, thereby effectively correcting its deficiency in the mulched trees. Fertilizer application increased foliar K of the unmulched trees, but only to an intermediate level of K nutrition. It also increased N foliar concentration further in the normal range. Both wind protection and mulch- ing separately, increased leaf area, and height and diameter growth. The combined effect of the two treatments was greater than the sum of their separate effects. Wind velocity up to 10 kilometers per hour did not affect leaf water tension as measured by the Scholander "pressure bomb." The mulching probably increased vegetative growth of black walnut at the site by correcting K deficiency. The ameliorative role of wind protection was probably due to increased temperatures in the shelter of the wind-breaks, and reduced mechanical injury to the leaves. Ghaus Mohammed Khattak Direct planting of container_grown black walnut would appear to hold considerable promise in farm-forestry due to minimizing root disturbance in planting, prolonging of the first growing season by several weeks, and enabling the plants to effectively absorb soil applied fertilizer even during the first year of application. EARLY RESPONSE OF PLANTED BLACK WALNUT TO SITE MODIFICATION BY Ghaus Mohammed Khattak A THESIS Submitted to Michigan State University in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY Department of Forestry 1968 ACKNOWLEDGMENT S I am deeply indebted to my major professor, Dr. Donald P. White, for guidance all through the planning, execution, and writing up of this study. My thanks are also due to all the members of my guidance committee: Drs. Jonathan W. Wright, Raymond J. Kunze, Gerhardt Schneider, and Robert S. Manthy for giving me most graciously of their valuable time. Guidance was always willingly given by Mr. Wade Nutter and Mr. Norbert Kulesza, Graduate Assistants, Forestry Depart- ment, and I gratefully acknowledge this debt. The study was made possible, initially, by the award of a U.N.S.F. fellowship to me by the F.A.O. of the United Nations and my deputation for studies abroad by the Govern- ment of West Pakistan. Expenses on field work in connection with the project were met from the McIntire-Stennis Law (P.L.-87-788). To the F.A.O. of the United Nations, the Government of West Pakistan, and the United States Govern- ment, therefore, I owe a debt of gratitude for financial assistance which made this work possible. ii VITA GHAUS MOHAMMED KHATTAK Candidate for the Degree of Doctor of Philosophy Final Examination: August 12, 1968 Dissertation: Early Response of Planted Black Walnut to Site Modification Outline of Studies: Major Subjects: Silviculture Minor Subjects: Forest Tree Improvement, Forest Physiology, Forest Ecology, Forest Economics, Soil-Plant-Water Relations Biographical Items: Born, January 3, 1924, Nushki, West Pakistan Undergraduate Studies: Islamia College Peshawar, Punjab University, 1939-1943 B.Sc. (Botany, Zoology), 1943 Graduate Studies: Pakistan Forest Institute, Upper Topa, 1947-1949 Superior Forest Service Diploma, 1949 Michigan State University, 1965- 1968 iii Experience: Member: M.S. Forestry, 1966 Ph.D. Forestry, 1968 Royal Indian Naval Volunteer Reserve (Liet.), 1943-1946 Divisional Forest Officer (Territorial), 1949-1955 Divisional Forest Officer (Planning), 1955-1958 Silviculturist, West Pakistan, 1959 Silviculturist, Pakistan Forest Institute, 1960-1965 Phi Kappa Phi Sigma Xi iv TABLE ABSTRACT TITLE PAGE . . . . . . . . ACKNOWLEDGMENTS. . . . . . VITA . . . .'. . . . . . . LIST OF TABLES . . . . . . LIST OF FIGURES. . . . . . LIST OF APPENDICES . . . . INTRODUCTION . . . . . . . REVIEW OF LITERATURE . . . OBJECTIVES AND SCOPE . . . THE EXPERIMENTAL AREA. . . Meteorological data. . . SOil O O O O O O O O O 0 OF CONTENTS AMELIORATION OF SITE CONDITIONS FOR PLANTED SEEDLINGS. . . Description of treatments. . . . . . Design of the experiment Operations conducted . . Subsidiary measurements. Wind velocity measurements . . . . . Soil moisture measurements . . . . . Soil-water tension measurements. . . V Page . i . ii . iii .viii . ix . x . 1 . 4 . 12 . l3 . 13 . 13 . l8 . 18 . 21 . 21 . 23 . 23 . 25 . 29 TABLE OF CONTENTS (Continued) Page Plant-leaf water tension measurements . . . . . . . 29 Effects of mulching and irrigation on soil moisture. . . . . . . . . . . . . . . . . . 34 0-30 cms. soil layer. . . . . . . . . . . . . . 34 30-60 cms. soil layer . . . . . . . . . . . . . 38 Effect of wind-breaks on temperature and relative humidity . . . . . . . . . . . . . . . 40 Air temperature . . . . . . . . . . . . . . . . 40 Soil temperature. . . . . . . . . . . . . . . . 40 Relative humidity . . . . . . . . . . . . . . . 42 Moisture tension inside the leaf. . . . . . . . . . 44 Diurnal variation in leaf water tension . . . . 45 Effects of the treatments on soil mineral nutrient elements . . . . . . . . . . . . . . . . . 49 Irrigation. . . . . . . . . . . . . . . . . . . 49 Mulching. . . . . . . . . . . . . . . . . . . . 50 Fertilizer application in plastic sacks . . . . 51 Effects of the treatments on foliar mineral nutrient elements . . . . . . . . . . . . . . . . . 54 First growing season response . . . . . . . . . 54 Irrigation. . . . . . . . . . . . . . . . . 54 Fertilizer application. . . . . . . . . . . 57 Second growing season response. . . . . . . . . 58 K foliar concentration. . . . . . . . . . . 59 N foliar concentration. . . . . . . . . . . 60 First growing season's growth responses to the treatments applied . . . . . . . . . . . . . 61 Leaf area . . . . . . . . . . . . . . . . . . . 61 vi TABLE OF CONTENTS (Continued) Second year's growth responses to the treatments applied . Leaf area. . . Height growth. . . Total height . Current year's terminal height growth. Diameter growth. . . . . . . . . . . 0 Diameter at 2.5 cms. above ground level. Diameter at the base of the current year's (1968) shoot. PLANTING CONTAINER-RAISED BLACK WALNUT Germination. . . . Comparison of planting container stock, 0 1-0 nursery stock, and germinating nuts. SUMMARY AND CONCLUSIONS. LITERATURE CITED . . APPENDICES . . . . . vii Page 65 65 68 68 70 7O 72 72 74 80 84 87 94 97 Table 10 LIST OF TABLES Role of mineral nutrients in plants . . . Meteorological data for Michigan State University Tree Research Center, 1967 and 1968 (part) growing seasons . . . . . Mean bulk densities and soil moisture content at 60 centimeters and 15 atmospheres tensions. . . . . . . . . . . Cultural practices and protective measures adopted during the investigations. . . . . . . . . . . . . . Effect of wind-breaks on wind velocity. . Daily course of soil moisture following irrigation. . . . . . . . . . . Effect of wind protection, mulching, and the interactions of mulching with wind protection on the total terminal height of black walnut during the middle of the second growing season following outplanting . . . . . . . . . . . . . . . Effect of wind protection, mulching, and the interaction of irrigation and mulch- ing on the current year's (1968) terminal height growth during the second growing season after planting black walnut. . . . Effect of wind protection, mulching, and interaction of irrigation and mulching on stem diameter at 2.5 cms. above ground level. (Second growing season after outplanting) . . . . . . . . Progress of black walnut germination under various treatments. . . . . . . . . viii Page 10 l4 17 24 26 36 69 71 73 82 Figure 10 11 12 13 LIST OF FIGURES Measurement of soil moisture with Nuclear-Chicago depth neutron probe and portable scaler . . . . . . . . . . Layout of black walnut plantation . . . Measurement of walnut leaf water tension by Scholander "pressure bomb" and soil water tension by Bouyoucos blocks. . . . . . . . . . . . . . . . . Leaf in the "bomb," with the petiole protruding through the rubber "compression gland" in the top. . . . . Moisture status of the 0-30 cms. soil layer under the treatments applied. . . Daily course of soil moisture in the 0-30 cms. soil layer, following irrigation. . . . . . . . . . . . . . . Moisture status of the 30-60 cms. soil layer under the treatments applied. . . Diurnal variation in leaf water tension on July 16, 1968. . . . . . . . Field planted walnuts in second growing season without wind protection and in the shelter of wind-breaks. . . . . . . Root system of 3-month old black walnut raised in soil mix in waxed cardboard milk containers . . . . . . . Field planting of greenhouse raised black walnut, six weeks from seed, in BR-8 blOCkS O O O O O O O O O O 0 O O 3-week old black walnut raised in soil mix in papier-mache plantable pots. . . Walnut leaves from Open grown trees and in the shelter of wind-breaks . . . ix Page 20 22 31 32 35 37 39 48 67 75 77 79 91 Appendix I II III IV VI VII VIII IX LIST OF APPENDICES Mean moisture content, of the 0-30 cms. soil layer of the site during July-September 1967, as determined by neutron probe . . . . . . . . . . . Mean moisture content of the 30-60 cms. soil layer of the site during July-September 1967, as determined by neutron probe . . . . . . . . . . . Effect of irrigation on exchangeable K at the 15 cms. soil depth. . . . . . Effect of mulching on exchangeable K at the 15 cms. soil depth. . . . . . . Soil available P, above and below perforated plastic sacks, one growing season after placement . . . . . . . . Soil exchangeable K, above and below the perforated plastic fertilizer sacks, one growing season after placement. . . . . . . . . . . . . . . N03-N content of soil, above and below the perforated plastic fertilizer sacks, one growing season after placement. . . . . . . . . . . . . . . Effect of irrigation on P foliar con- centration, 1-0 black walnut, one growing season following outplanting, August 20, 1967. . . . . . . . . . . . Effect of irrigation on K foliar concentration, 1-0 black walnut, one growing season following out- planting, August 20, 1967. . . . . . . Effect of irrigation on Mg foliar con- centration, 1-0 black walnut, one growing season following outplanting, August 20, 1967. . . . . . . . . . . . X Page 97 98 99 100 101 102 103 104 105 106 Appendix Page XI Effect of Irrigation on Ca foliar concentration, 1-0 black walnut, one growing season following outplanting, August 20, 1967 . . . . . . . 107 XII Effect of fertilizer application in perforated plastic sacks on N foliar concentration, 1-0 black walnut, one growing season follow- ing outplanting, August 20, 1967 . . . . . 108 XIII Foliar concentrations of mineral nutrient elements delimiting various ranges of nutritional status in California walnut. . . . . . . . 109 XIV Mean foliar concentration on July 17, 1968, 1-0 black walnut, second growing season following outplanting. . . . . . . . . . . . . . . . 110 XV Mean foliar N concentration on July 17, 1968: 1-0 black walnut, second growing season following outplanting. . . . . . . . . . . . . . . . 111 XVI Relation of oven-dry weight and leaf area of 1-0 black walnut, one growing season after outplanting, 'determined at the Tree Research Center on September 15, 1967 . . . . . . . 112 XVII Leaf area of 1-0 black walnut, under the treatments applied, one growing season after outplanting. 'Measured September 15, 1967. . . . . . . . ll4 XVIII Leaf area of best tree in each plot on July 15, 1968; 1-0 black walnut, second season after outplanting. . . . . . . . . . . . . . . . 115 XIX Mean total height on July 22, 1968; 1-0 black walnut, second season following outplanting. . . . . . . . . . . 116 XX Mean height of the current year's (1968) terminal shoot on July 22, 1968; 1-0 black walnut, second season following outplanting . . . . . . . ll7 xi Appendix XXI XXII Page Mean diameter 2.5 cms. above ground level on July 22, 1968; '1-0 black walnut, second season following outplanting . . . . . . . . . . 118 Mean diameter at the base of the current year's (1968) terminal shoot on July 22, 1968; 1-0 black walnut, second season following outplanting . . . . . . . . . . 119 xii INTRODUCTION Black walnut (Juglans nigra L.) timber is highly prized throughout the world. It has consistently been in demand within the United States since the Colonial times and its export to the European countries and to Japan has increased ten-fold in the past ten years (QUIGLEY and LINDMARK, 1966). Because of this heavy use of high-quality stock, its annual cut now exceedsgrowth by 6 million board feet (RANDALL, 1966). Though the current demand for quality walnut is high, dwindling supplies combined with increasing costs are likely to accelerate the pace of its replacement by substitute products - notably the photographic reproduc- tions. Can this be avoided? Given the current trend of in- creasing per capita income in the United States, and the human desire for the authentic, walnut can probably hold its own against substitutes in the foreseeable future provided it does not become so scarce as to lose its price advantage against its plausible substitutes. To insure the future of black walnut in the high-class wood-using industries, there- fore, our aim should be to increase the available supplies of quality material as quickly as possible. According to Cliff (1966), supplies can be increased by stimulating 1 diameter growth of crop trees and by increased planting of genetically superior stock with the most intensive cultural practices feasible economically -- objective: rotation of 40 years for saw timber. Walnut occurs naturally as scat- tered trees, it can therefore be grown singly or in small groves by most farmers. With the high prices that the trees fetch, the surplus of farmland, and the Government incentives for non-farm land use, it should be economically feasible for a large number of small farmers to invest in intensive growing of walnut. To produce quality material at short rotations, it is necessary to provide optimum growing conditions to the species. The approach has so far been to recommend walnut planting only on naturally fertile land. Being scarce, such land usually is under more intensive farm uses. The chal- lenge for the Silviculturist, therefore, is to devise mea- sures for ameliorating the site conditions of below average farmland to create a more favorable environment for crops of black walnut, also to improve planting and post-planting techniques to insure survival and promote rapid early growth. This is the objective of the present study. An attempt has been made in this study to investigate a number of practices which may increase the growth rate of walnut. These practices fall under the following categories: 1. improvement in the internal water balance of the plants by irrigation, wind-breaks, mulches, and control of competing vegetation. 2. improvement in the soil nutrient status by the use of fertilizers. 3. improvement in early growth and survival through the development of better container plant- ing techniques. REVIEW OF LITERATURE Since very little has been published on the effects of the treatments applied on black walnut specifically, this review will include the responses of all the plants studied so far to these treatments with the object of clarifying their mode of action on plant growth in general. Mulching The major role of organic mulches is the conserva- tion of soil moisture, though they may also alter the availability of certain nutrients to plants. Mulches and Soil Moisture Conservation: Mulches conserve soil moisture by increasing the rate of infiltration and decreasing the evaporative losses from the soil surface. By keeping down weeds, they also decrease transpiration losses. Organic mulches increase soil infiltration rates by offering protection against rain drOp impact, improv- ing soil aggregation, and decreasing the frequency of freezing of the surface soil during winter. Duley and Kelly (1939) found that straw and stubble mulches increased infiltration by preventing the formation of a compact surface layer due to rain drop impact. By favoring the multiplication of fungi, bacteria, and actinomycetes, mulches induce greater aggregation of the surface soil which is conducive to higher infiltration (JACKS, BRIND, and SMITH, 1955). Infiltration is also favored because earthworms increase under organic mulches: their burrows facilitate infiltration directly and their castings increase it indirectly by improving soil aggregation (VON NEIROP and WHITE, 1958). Infiltration is prevented when surface soils freeze. Organic mulches reduce this incidence, thereby favoring infiltration. Kohnke and Werkhoven (1963) found the frequency of freezing at 2.5 cms. depth to be three times as great in bare soils as in the mulched. The potentialities for decreasing evaporation losses from the soil have been analyzed by Lemon (1956). Mulches, according to him, significantly decrease evaporative losses from the soil only when the soil surface is wet. From field experiments, Russel (1939) concluded that mulches conserved soil moisture only when the rains were adequate and frequent. Depth of mulching, from 4 to 36 metric tons per hectare did not influence moisture conservation. Mulches and the Availability of Nutrients: Decomposable mulches, in general, increase the availability of P and K. They may increase or decrease N levels depending on their C/N ratio. Studying the effect of organic mulches on coffee in Kenya, Robinson and Hosegood (1959) concluded that mulches reduced soil acidity; increased organic carbon, Kjeldahl N, exchangeable K, and available P; and decreased exchangeable Ca and Mg. Tukey and Schoff (1963) obtained increases in available P and exchangeable K with decompos- able mulches. But Ca, Mg, and soil pH were not affected. Beneficial Effect on Black Walnut: Seidel (1946) reported a doubling in the height growth of black walnut under broomesedge (AndrOpogon virginicus L.), wheat straw, and old hardwood sawdust mulches, five years after planting of 3 year old black walnut stocks grafted with one year old grafts of nine horticultural varieties. No explanation was given for this effect. Wind Protection Though winds up to about 3 kilometers per hour may increase assimilation by increasing C02 diffusion into plant leaves, higher wind velocities are detrimental to growth. Thus Martin and Clements (1935) observed a progressive de- crease in leaf area, stem height, diameter, and dry weight of Helianthus annuus L. when wind velocity was increased from 8 to 24 kilometers per hour. Wind velocities up to 3 kilometers per hour increased transpiration rates by about 20 to 30%; at 26 kilometers per hour the increase was 50%. Similar decreases ingrowth were observed by Whitehead (1963) in corn (Zea mays L.) and Helianthus annuus L. when the wind velocity was increased from zero to 48 kilo- meters per hour. The mechanism by which wind reduces plant growth is not known. Both Wadsworth (1959, 1960) and Whitehead (1963) inpute the characteristic effects of wind to increased in- ternal water stress in the plant under high wind velocities - the former contending that the wind-induced decrease in growth was due both to decreased leaf area as well as de- creased assimilation rate, the latter maintaining that de- creased leaf area alone was responsible for decreased growth, except in extreme cases when the photosynthetic apparatus might also be affected. Finnell, as early as 1928, reported considerable mechanical injury and deformation of potted marigolds ex- posed to high wind velocities, in addition to reduced height growth, increased time of maturity, reduced yield of dry matter, and increased number of side branches. Irrigation Irrigation is the most direct means of augmenting soil moisture. Plant growth, however, is determined directly by plant water stress and only indirectly by the soil water status. The effect of irrigation on plant growth will therefore be conditioned by the entire complex of factors which determine the balance between water loss and absorption within the plant. After over 30 years of controversy over whether plant growth was retarded by a reduction in soil moisture content from field capacity to permanent wilting point, it is now generally agreed that vegetative growth starts declining as soil water is de- creased from somewhat below the field capacity (STANHILL, 1957). Recent work e.g. Sands and Rutter (1959) with 1 and 3 season old potted Scotch pine (Pinus sylvestris L.); Jarvis and Jarvis (1963) with potted seedlings of birch (Betula verrucosa Ehrh), aspen (Populus tremula L.), Scotch pine and Norway spruce (Picea abies (L.) KarSt); and Uriu (1964) with 8-10 year old peaches; indicates that an in- crease in soil tension above about .5 atmospheres is detri- mental to growth. Khattak (1965) working with 6 year old "shisham" (Dalbergia sissoo Roxb.) growing on clay loam soil in the irrigated plantations of West Pakistan observed an almost linear increase of wood production with an increase in the depth of water delivered to the trees during the irrigation season (mid-April to mid-October). The volumes of wood produced under different depths of irrigation are given below: Depth of water delivered Volume of wood produced per hectare (meters) (over bark, cu. meters solid) 0.45 63 0.91 106 1.36 148 1.82 190 2.27 232 Mineral Nutrient Elements Certain mineral nutrient elements are essential for the Optimum growth and reproduction of plants; the multi- plicity of functions performed by them are illustrated in Table 1. Of these nutrient elements, N, K, and Mg are usu- ally deficient for tree crops -- in particular for walnut. N is deficient most often and needs to be added in the largest amounts (REUTHER, EMBLETON, and JONES, 1958; PROEBSTING and SERR, 1966). Assessing the Nutrition Status of Tree Crops: The con- siderable depth to which trees exploit the soil for mineral nutrients usually makes soil analysis a poor method for assessing their nutrient status, better correlation usually being obtained between tissue analysis and nutrient status. This is so in walnut (PROEBSTING and SERR, 1966). The plant tissues most often analyzed are the leaves, because they are present throughout the growing season, can easily be identified, and their removal does not harm the plant (KENWORTHY, 1967). Basis for the Validity of Tissue Analysis: From sand and water culture experiments, and field experiments, it is possible to establish for each plant species the average content of a particular nutrient element associated with desirable growth characteristics. Such "standard values" have been shown to be remarkably constant for a particular TABLE 1. 10 Role of mineral nutrients in plants (After Evans and Sorger, 1966) Mineral Nutrient Functions performed in plant processes N P Ca Mg Fe Cu Zn MO C1 C0 Essential component of proteins, amino acids, nucleic acids, and co-enzymes Component of sugar phOSphates, nucleic acids, nucleotides, co-enzymes, phospholipids, phytic acid, and other compounds; key role in energy transfer Co-enzyme for a large number of enzymes Component of cysteine, cystine, and methionine in pro- teins; constituent of lipoic acid, co—enzyme A, thiamine pyrophosphate, glutathione, biotin, adenosine-S-phosphosulfate, and 3-phosphoadenosine- 5-phosphosulfate and other compounds As calcium pectate, a constituent of the middle- 1amellas of plant cell walls; co-factor for certain enzymes involved in the hydrolysis of ATP and phospholipids Required non-specifically by a large number of enzymes; involved in phosphate transfer; constituent of the chlorophyll molecule Constituent of cytochromes, and of non-heme iron proteins; involved in photosynehesis, nitrogen fixation, and respiratory-linked dehydrogenases Activation of some dehydrogenases, decarboxylases, kinases, oxidases, peroxidases, and certain other enzymes Probably involved in carbohydrate transport Component of ascorbic acid oxidase, tyrosinase, laccase, monoamine oxidase, uricase, cytochrome oxidase, and galactose oxidase Constituent of alcohol, glutamine, and lactic dehydrogenases; carbonic anhydrase, carboxypeptidase B, and other enzymes Constituent of nitrate reductase and xanthine oxidase; necessary for nitrogen fixation Required for photosynthetic reactions involved in oxygen evolution Essential for free-living and symbiotic nitrogen fixing micro-organisms 11 plant species, being dependent mainly on nutrient status and affected by environmental conditions only to a minor degree. Therefore, whenever the observed value of a nu- trient element in a tissue sample is much below the "standard value" characteristic of the species, a defi- ciency of that element can be assumed and a response ex- pected when it is supplied; even though the plant may not be exhibiting any external symptom of the deficiency. "Standard values" have not so far been developed for black walnut but have been for California walnut (Juglans Californica, S. Wats.) and Finn (1966) has used them to indicate a possible deficiency of K in Iowa soils for the maximum growth of black walnut. Mineral Nutrition of Black Walnut: Systematic studies on the mineral nutrition of black walnut have recently been started (FINN, 1966) but nothing conclusive appears to have been reported so far on the response of the species to fertilization during its early stages of growth. OBJECTIVES AND SCOPE The study was designed to find out if early growth of black walnut could be increased when planted on aban- doned farmland. The site ameliorative practices tested were wind protection, irrigation, mulching, and fertilizer application. In addition to measuring gross plant re- sponses to the treatments applied, their effects on such environmental factors as wind velocity, soil moisture, soil and air temperature, were also evaluated. Foliar analyses and leaf water tension measurements were also conducted to gain a better insight into plant response. Because chemical weed control, careful planting practices, and pruning are prerequisites to intensive Silviculture, these were adopted as standard practices over the entire experiment. Anticipating the growing popularity of container- stock planting in farm-forestry, a preliminary investi- gation was initiated to compare the growth rates of seed- lings raised in "BR-8" wood pulp fibre blocks and papier- mache plantable containers, with 1-0 stock planted bare rooted and germinating nuts planted directly in soil. 12 THE EXPE RIMENTAL AREA The field experiments were conducted at the Tree Research Center, in the southeast corner of the Michigan State University campus. Features of the experimental area, relevant to these investigations, are described below: Meteorological Data: The meteorological data for the Station for 1967 and l9689rowing seasons are given in Table 2. Low temperatures on the 6th and 7th of May 1968 (minimum temperature recorded in the weather station of the Tree Research Center, -3 and -2°C, respectively, killed all the leaves which had just started to develop. A milder frost occurred on May 18 (minimum temperature recorded at the weather station, 0°C) and killed the young leaves of the plants not protected from wind. Soil: Soil types: the soil types represented in the experimental area are: Kalamazoo sandy loam; well-drained soils with a sandy loam to loam plow layer; 25-64 cms. thick sandy clay loam to clay loam subsoil; pervious sand occurring at 61-107 cms. with bands of variable thickness which are either loamy sand or sandy loam in texture. Metea sandy loam; well to moderately well- 13 14 mm I a ma em Hm em I. mm m.oH m.m mane Hm I m Ha mm ma em mm om w.m m.om mach ma I mI N mm Ha ma we mm H.m N.HH we: mwma ha I o 5 mm m mm we mm m.ma m.n .pmom SH I e aa Hm SH mm he mm m.ma e.m “mamas Hm I a an mm om em as ea o.ea o.m mane mm I m ma mm ma em Hm om m.ea h.ma mash mama .GHE .GHE .xwe .xme .GHS .xdz A.mEUV “.mEov mo mmcmm new: mo modem new: va soap coaumo Oo .mHSDMHMQEmu Ham NUHUHESQ Imuomm>m IHmHomHm sumo: o>eumawm Gem Hmuoa Hmuoe mcommmm.mcflzoum “Dummy mmma pom bmma .Houcmo noummmmm wows wuamum>flcb mumum cmmasoflz How sump Hmoamoaonomuoz .N mamma 15 drained with 45 to 61 cms. of sandy loam over loam till, moisture conditions varying with the depth to the loam material. Chemical Properties: The soils are acidic and of low fer- tility, deficient especially in K. The soil chemical properties of the site are characterized below: Loss on Avail. Exch. Exch. Exch. Ph ignition NOB-N P K Ca Mg % (ppm) (kilograms per hectare) 5.6 2.1 16 26 136 895 73 Moisture Retaining Characteristics: The moisture retained by the soil at the 60 cms. and the 15 atmospheres tensions was determined for the 15, 30, and 45 cms. depths. Two of the 16 plots in each replication were picked out at random and duplicate disturbed and undisturbed samples taken from each of the three depths. The moisture content at 60 cms. tension was determined by saturating undisturbed soil cores for 48 hours and then placing them on a tension table at 60 cms. tension until no more water could be extracted out of them. This normally took about 24 hours. The cores were then oven-dried for 48 hours and the weight of water lost expressed as a per cent of the volume of the cores. frhese undisturbed cores were also used for the determination o f bulk density . The moisture content at 15 atms. tension was deter- Inined by the porous plate apparatus. The disturbed samples 16 were saturated on the porous plate for 24 hours and then subjected to a pressure of 15.5 kilograms per square cm. until no more water could be extracted from them. This normally took about 24 hours. The samples were then oven- dried and the per cent moisture content by weight converted to per cent moisture content by volume, by multiplying with the bulk density for the sampling point. A summary of the data is given in Table 3. 17 >.mH h.mm mm.H Ih.m m.o Im.wa m.om Imm.H mm.a me m.oa o.mm wh.a Ie.a m.m Ia.ma v.am Ime.a mm.a om m.m o.nm mm.a Io.m m.m IN.>H «.mm Ihm.a he.a ma mmcmm new: modem cams madam new: “.mEov coflmcwu monogamoapm ma coemcmu mumumafiucmo om Hmumfiflocoo oaooo npmmo Hem memum madao> an ucmo mom .ucmucoo myopmfloa Hfiom .muflmcmp xasm wooemcou monogamofiuw ma one mumoofiflpcoo om pm ucmucoo oHSUmHoE HHOm one mmflufimcop xaso new: .m mamde AMELIORATION OF SITE CONDITIONS FOR PLANTED SEEDLINGS The principal field study comprised an evaluation of the effects of wind protection, mulching, irrigation and fertilization on the growth of planted l-O black walnut seed- lings. The importance of chemical weed control was so well known that it was applied uniformly rather than as a separ- ate treatment. Description of Treatments: Wind protection: wind protec- tion, where prescribed, was provided by three thicknesses of 1.4 meters high snow fence. The rows of walnut were planted 1.5 meters to the leeward of the wind-break. The L-shaped wind-breaks were oriented with their long arms roughly north-south, across the predominant wind direction. Short cross arms, 5 meters in length, were provided at the southern ends of the wind-breaks to offer protection from the south-westerly winds. Irrigation: due to the onset of a prolonged dry spell towards early spring, all the plants were irrigated about a week after planting to avoid heavy mortality. Subsequent irrigations were applied only to the plants for which the treatment was prescribed. Unless it had rained more than 18 19 2.5 cms. during the previous week, 7.5 liters of water were applied once every week to all the plants allotted to this treatment. The water was poured inside of retain- ing rings about 2.2 cms. in radius and 5 cms. high, made by encircling each plant with aluminum "lawn-stop" strips. The irrigations were applied on the 19-20 May; 2-3 June; 13, 21, 28 July; 2, 8, 17, 22 August. Beyond the 22nd of August, it was not considered necessary to irrigate as by then active growth had ceased and soil moisture generally remained adequate after this date. Soil moisture was measured once every week with a Nuclear-Chicago Corporation model P 19 neutron depth mois- ture gauge equipped with model 2800 portable scaler, (Figure 1), positioning the probe with its center at 15 and 45 cms. below the soil surface. Mulching: about 2.5 cms. thick layer of fresh hardwood chips was applied to 3 x 1.5 meter strips, with a group of three plants representing each treatment in the center of the strip; the mulch thus covered the soil for at least 75 cms. all around the plants. Fertilizer application: a plastic sackl containing 56 grams of 16:8:16 soluble fertilizer (WHITE and ELLIS, 1965) was buried with each plant for which this treatment was indicated. lObtained commercially from S & D Products, Inc., Prairie duChien, Wisc. Contain ammonium nitrate, ammonium phosphate and muriate of potash. Figure l. 20 ' . . .._ ' .p' Al’i‘u-“xx 3 3'31" 1m: .__“ Measurement of soil moisture with Nuclear- Chicago depth neutron probe and portable scaler. 21 The sacks were placed about 15-23 cms. deep and 7 cms. to the side of the root. Four equally spaced holes 1.2 mm in diameter had been punched through the sacks to permit slow diffusion of nutrients into the soil. Design of the Experiment: A split-split plot design was used with the treatments arranged as in Figure 2. This design was adOpted for the following reasons: 1. The first main split was provided because it was considered advisable to keep the wind-breaks long enough to prevent wind whipping around the edges. Had 3-4 meter long individual barriers been provided to each treatment comprising three plants, the edge effect would probably have been considerable. 2. The second main split was provided because it was considered preferable to keep together all irrigated subplots to minimize the edge effect of irrigation on the unirrigated plots. As a further precaution against this, a plastic sheet of heavy gauge was buried to a depth of one meter between the irrigated and unirrigated second split main plots. Operations Conducted: Planting: Black walnut l-O stock (seed source 0-3373, Kellogg Farm, Kalamazoo County) which had been root-pruned at 20 cms. depth the previous fall, was lifted from the nursery beds on May 1, 1967, and stored 22 BUHDE + HmNHHHuumw HSHm SOHDE EUHDE QOHSE on .HmNHHHDHmm 0c HSOE 0c .HmNHHHuumm osz o o .HmNHHHuHmm 0c 2 m I-INMQ' menu pwummHHHHcs onon + own“ UmummHHHH mquHm * GOHuompoum ch3 on 03 GOHuomuoum UGHB H3 w H m N N v H m +++ +++ +++ +++ ere 44* «ee 44* H N m w m w H N +++ +++ +++ +++ res «sk «rs ¥¥¥ N m w H N m w H see see «es «es +++ +++ +++ +++ H N v m m w H N +++ +++ +++ +++ «re «se est see AIV muoums m.H H v N m m N v H +++ +++ +++ +++ see e«« «rs ere xmmnn UGHB v H N m H N m H see see see see +++ +++ +++ +++ H3 m N H v N v H .m «es see see see +++ +++ +++ +++ z _¢IIII 20HummHHuH mo pommmo mmpm mconoso How ummnm UHDmmHm v N m w m H see «e. 444 44* +++ +++ +++ +++HH” N v H m N H see ««« res es ++ +++ +++ +++x 03 N v H m m v N H +++ +++ +++ +++ 44* see «44 «e« I. mumumfi mm .GOHHMpamHm usch3 xOMHn mo psommq .N ousmHm sxeqem \sxeqem 23 in the cold room at about 4°C. During the first week of May, soil pits about 30 cms. in depth and 15 cms. in diameter were excavated by a tractor operated post-hole digger. The seedlings ranged in height from 25-35 cms. and were graded into 2.5 cm. classes. While planting, on the 13-14 of May, the same height class was planted in each replication, start- ing with the largest from replication V and working towards replication I with the successively smaller. To further even out the effect of variation in size, the largest plants in each 2.5 cms. class were planted at the center of the group of three plants representing a treatment. Almost the entire root system of the stock planted comprised the 20 cms. long stub of tap root, with few fibrous roots. Cultural prac- tices and protective measures adopted are given in Table 4. Subsidiary Measurements Wind velocity measurements were taken over a period of about a month to assess the relative effectiveness of wind-breaks. Soil moisture was measured once every week from July 1 to October 3 in 1967 and soil moisture tension checked during June and July 1968 in conjunction with plant leaf water tension measurements. Wind Velocity Measurements: Wind velocity measurements were carried out with calibrated and paired totalling cup anemometers; one pair of anemometers in the open and the other behind the wind-breaks. The individual anemometers of a pair were spaced about 9 meters from the ends of the protected or non-protected first split main plots, and the 24 \ TABLE 4. Cultural practices and protective measures adopted during the investigations Practice Date applied Comments Pruning of Nov. 15, 1967 Subsequently, as multiple leaders June 15, 1968 required by individ- and side branches ual plants Chemical weed control Amitrol - T May 3, 1967 2.27 kilograms per hectare pre-planting foliar spray June 15, 1967 2.27 kilograms per hectare post-planting foliar spray, plants covered with empty cherry cans Paraquat Aug. 1, 1967 4.75 liters per hectare foliar spray, plants covered with empty cherry cans Amitrol - T May 1, 1968 2.27 kilogram per June 15, 1968 hectare foliar directed spray Insect and disease control Malathion June 7, 1967 10 milliliters of Aug. 2, 1967 57 per cent emulsion June 3, 1968 in 3.8 liters of water Bordeaux July 20, 1967 2:1:50 spray, applied mixture to wet the foliage thoroughly 25 same distance apart from each other. The height of instal- lation above ground was 45 cms. The wind-breaks reduced wind velocity by about 50 per cent in most of the replications (Table 5). The reduc- tion in Replication IV was only about 20 per cent probably because the wind protected half of the replication was on higher ground as compared to the unprotected half. Soil Moisture Measurements: Measurement of soil moisture was confined to the unfertilized subplots assuming that the adjacent subplots with fertilizer treatment would be at the same moisture content. Installation of soil moisture access tubes: 60 cms. long galvanized iron access tubes, with the inside diameter just large enough to permit passage of the neutron probe, were. driven into slightly narrower augur holes to get a tight fit with the soil, leaving 5 cms. of the tubes above ground. The tubes were capped with rubber stoppers. Field calibration of the neutron scattering soil moisture meter: field calibration was considered necessary for two reasons: 1. Since measurements were planned at 15 cms. (in addition to 45 cms.) depth, considerable escape of neutrons was anticipated. A correct estimation of moisture content would therefore only be possible if the probe counts at this depth were related to the actual moisture content. 26 me mam com mmuea .ummm > om emm emm mHIoH .ummm >H om ems on sum .ummm HHH Hm oeHH emm mmumm .maa HH me was ems Hmumm .mea H some may cH umnp AmnmumfioHHxv mo unmouom mm mxmmuo ammo map AmHmumEoHHxv mxmmuo IchB map pcflnmo cH popuoomu Ich3 map chnmo GOHum>Homoo “ones: popuooon chs Hmuoe UGHS Hmuoe popuoomu UGHS Hmuoa mo UOHHmm cOHpmoaHmom NDHOOHm> UGH3 co mxmmuolchB mo Dommmm .m mqm¢a 27 2. Thickness as well as the material of the access tubes used were different from those used in factory calibration. The data for the field calibration were obtained in the following manner: 1. The undisturbed core samples taken for the deter- mination of the moisture content at 60 cms. tension were used to establish a relationship between the per cent moisture content by volume as determined gravimetrically and the ratio of counts per minute (cpm) soil over counts per minute in the shield of the neutron moisture meter. To enable this, two cores were taken with their centers at each of the 15, 30, and 45 cms. depths after neutron counts had been made with the probes centered at these depths. 2. Since none of the above measurements were taken at a high enough moisture content, supplementary measurements were taken with the Veihmeyer tube when the soil moisture content was high. For this purpose, an access tube was installed at the site of measurement and neutron counts re- corded at 15, 30, and 45 cms. depths. Three soil samples were then withdrawn along different radii, at about 2.5 cms. from the access tube, from each of 0-15, 15-30, 30-45, and 45-60 cms. depths. 28 The per cent moisture content of the samples by volume was determined gravimetrically. The values for 0-15 and 15-30 cms. depths for each measuring site were averaged and considered to represent the average moisture content of the upper sphere of soil measured by the cpm soil/ cpm shield ratio of the neutron moisture meter with the probe positioned at 15 cms. from the soil surface. In the same manner, the moisture content of the samples withdrawn from the 30-45, and 45-60 cms. depths were considered to repre- sent the soil moisture content of the lower sphere of soil corresponding to the moisture content indicated by the cpm soil/cpm shield ratio ob- tained with the probe at the 45 cms. depth. From the data obtained in the above-mentioned manner, separate regression equations were worked out giving the relationship between neutron moisture meter ratios and the corresponding per cent soil moisture content by volume with the probe at 15 cms. (Y = 0.6539 + 27.2211 X) and 45 cms. (Y = 2.4512 + 22.3609 X) depth. Measurement procedure: Before starting measurements at any replication, five successive one-minute counts were taken with the probe in the shield, and the average used as the denominator of the ratio cpm soil/cpm shield. While taking counts in the soil, the base of the shield of the probe was 29 rested on an 8 cms. long aluminum sleeve placed around the above-ground portion of the access tube. The probe was first lowered until its center was 15 cms. below the soil surface. A one-minute count was taken at this depth and then the probe lowered to the 45 cms. depth where another count of a similar duration was taken. The ratios cpm soil/cpm shield for both the depths were converted to per cent soil moisture by volume using Tables prepared from the relevant regression equations. Soil-Water Tension Measurements: In June 1968, a Bouyoucos block (BOUYOUCOS, 1961) was embedded 30 cms. deep and 15 cms. to the side of the root of the middle plant in each un- fertilized 3-tree plot. This reduced the number of blocks needed assuming that the moisture status of the fertilized and unfertilized plots would be about the same provided all other treatments were identical. The blocks were used to record soil moisture tension while measuring plant water tension. Plant-Leaf Water Tension Measurements: Since walnut has a large root system, it is not possible to characterize the soil moisture status in its root zone by one or two measure- ments. Moreover, soil moisture is not the only factor de- termining the availability of water within the plant for various life processes and for the maintenance of turgor. Perhaps of greater importance are the various environmental factors which govern the steepness of the vapor pressure 30 gradient from the plant leaf to the atmosphere. The inter- play of all these factors would be reflected in the tension with which water is held within the plant at any instance. Especially for deep rooted tree species, this tension would perhaps indicate more meaningfully than soil moisture alone can,.the moisture stress to which the plant is subject at any time. When a leaf is severed from an actively transpiring plant, the water in its xylem elements recedes a certain distance depending on the magnitude of the tension at which it was held within the plant. If the cut leaf is placed inside a "pressure bomb," with its petiole protruding through a rubber "compression gland" (Figures 3 and 4) and the pres- sure within the "bomb" increased, the water which had re- ceded from the cut end would be forced back towards it until it starts bubbling out. The pressure at which this water just wets the cut end can be considered to equal the tension at which water was held in the xylem elements of the leaf just before it was cut (SCHOLANDER et al., 1965). The "pressure bomb“ was used to find out if any of the treatments, especially wind protection, influenced the tension at which water was held inside the leaf. A 15 cms. length of rachis was standardized as the suitable size of leaf to use for each measurement. About .25 cms. of the petiole was allowed to protrude out of the "bomb." Only mature leaves were used for the measurements. The leaf was placed inside the "bomb" within about half a minute of Measurement of walnut leaf Scholander "pressure bomb" sion by Bouyoucos blocks. of wind break and position mometer. g; 3% n afifim water tension by and soil water ten— View shows detail of totalizing ane— Figure 4. 32 / m.» _H: -——-«---_.._._..,1_.,1_—- I Leaf in the "bomb," with the rachis protruding through the rubber "compression gland" in the top. 33 cutting. To enable better comparison, the readings for plants protected from wind were taken within five minutes of those in the open. Air temperature was recorded at each tension measurement, wind velocity and relative humidity at l-2 hour intervals, and soil water tension once during each day of measurement. Effects of Mulching and Irrigation on Soil Moisture 0-30 cms. Soil Layer: The moisture status of the 0-30 cms.- soil layer during the 1967 growing season is depicted by Figure 5 and the complete data in Appendix I. Wind has not been taken into account in Figure 5 because neither its main effect nor its interaction with any treatment was signifi- cant statistically. Of the treatments applied, both mulching and irriga- tion maintained the soil at a significantly higher (1% level) moisture content as compared to the control. To follow the daily course of soil moisture after irrigation, the soil moisture content of the irrigated plots was measured 6 hours after the irrigation on August 8, and then on 9, 10, ll, 13, and 15. There was no rain during this interval. The results are given in Table 6 and Figure 6. The data suggest the following: 1. Out of the treatments applied, irrigation plus mulching maintains the highest moisture content in the 0-30 cms. soil layer throughout the week between successive irrigations. 2. Irrigation, unaccompanied by mulching, maintains a higher moisture content than the unirrigated 34 35 under the treatments applied. 26 22 20 I 18 Z 2 «"~ 316 ,, o > 0 >1 “314- op 3 C. 4 ° 810 G (D {I *5 8- p m H S 6- 4- 24 O I T I f | l T l l l 7 13 21 28 8 15 22 29 6 12 19 July August September 1967 O Irrigated, Mulched .A Not Irrigated, Mulched 0 Not Mulched, Irrigated [3 Not Mulched, Not Irrigated A Average moisture content at 15 atmospheres tension Figure 5. Moisture status of the 0-30-cms. soil layer 36 TABLE 6. Daily course of soil moisture following irrigation Treatment 1 2 August, 1967 8 8 9 10 11 13 15 (Mean moisture content, per cent by volume)3 Irrigation plus mulching 15.9 23.0 19.7 18.3 17.6 16.9 15.3 Irrigation, no mulch 12.6 19.9 17.6 15.7 14.8 13.5 12.6 No irrigation, mulch 14.7 13.2 No irrigation, no mulch 9.7 8.6 lBefore irrigation 6 hours after irrigation 3Mean moisture content at 60 cms. tension = 22.4% Mean moisture content at 15 atmospheres tension = 5.6% 37 241 22- l—I oo % By Volume H H :5- ON I GL1 l—' N 1 Moisture Content, H O ' I O V I I ‘ ‘ 8 9 10 11 12 l3 14 15 Days (August, 1967) Irrigated, Mulched Not Mulched, Irrigated Not Irrigated, Mulched Not Mulched, Not Irrigated Average moisture content at 15 atmospheres tension >OI>DO Figure 6. Daily course of soil moisture in the 0-30 cms. soil layer, following irrigation. 38 mulched plots only during the first half of the week. 30-60 cms. Soil Layer: None of the treatments applied, in- cluding irrigation, had any effect on the moisture content of the 30-60 cms. layer. The moisture status of the 30-60 cms. soil layer is depicted in Figure 7. Complete data are given in Appendix II. % By Volume Moisture Content, 39 14- 12. 10s 8d 6 4. 2.. 0 j l I U I U I I l V I 13 21 28 8 15 22 29 6 12 19 26 July August September 1967 O Irrigated, Mulched IA Not Irrigated, Mulched a Not Mulched, Irrigated {3 Not Mulched, Not Irrigated A Average moisture content at 15 atmospheres tension Figure 7. Seasonal moisture status of the 30—60 cms. soil layer under the treatments applied. Effect of Wind-Breaks on Temperature andIRelative Humidity Air temperature and relative humidity were recorded in the open and behind the wind-breaks on July 16 and 20 from sunrise to sunset and on July 21 from about 12 noon to 4:30 p.m. Air temperature was measured by mercury thermome- ters and relative humidity by sling type psychrometer. The measurements were carried out at the level of the plant crowns . Air Temperature: Air temperature was 1 to 4°C higher be- hind the wind-breaks as compared to the open. This reflects their effect in reducing wind velocity. The greatest dif- ference in temperatures occurred about 11:00 a.m. to about 4:00 p.m. The data for July 16, 1968 (Replication II) are representative of the general trend found dur- ing the latter part of July 1968 (p. 41). Soil Temperature: Soil temperature was recorded at 7 cms. depth on July 28, 1968, in Replication V, in two mulched and two unmulched plots, in the open and behind the wind- break. The data are recorded on page 41. 40 41 Wind velocity Time of Air temperature (°C) (kilometers per hour) observation Open Wind-break Open Wind-break 7:30 a.m.. 22 22 8.0 3.0 9:30 a.m. 29 29 11.0 3.2 11:00 a.m. 31 33 7.7 2.4 1:00 p.m. 33 37 6.6 2.1 3.00 p.m. 33 36 4.5 1.5 5:00 p.m. 31 32 7.0 1.3 7:00 p.m. 31 32 5.3 1.6 9:00 p.m. 25 26 0.0 0.0 Time of Open Wind-break observation UnmuIChed Mulched Unmulched Mulched (mean soil temperature, °C) 10:00 a.m. 19 20 21 21 10:30 a.m. 20 20 22 22 11:00 a.m. 21 21 23 22 11:30 a.m. 22 21 24 23 12:00 noon 23 22 25 23 1:00 p.m. 23 22 26 24 2:00 p.m. 24 23 27 24 3:00 p.m. 24 23 28 25 42 Thus on the day Of observation, wind-breaks increased soil temperature at 7 cms. depth in the unmulched plots by 4°C at 3 p.m. The increase was 2°C in the mulched plots. Mulching reduced soil temperature during the noon and after- noon hours by a maximum Of 3°C in the plots protected from wind and 1°C in the plots in the open. Relative Humidity: Relative humidity behind the wind-breaks remained virtually the same as in the Open, as brought out by the following figures for July 20, 1968 (Replication III): Time Of Relative humidity (%) observation Open Wind-break 7:00 a.m. 97 97 8:00 a.m. 77 77 10:00 a.m. 69 70 11:00 a.m. 63 63 12:00 noon 56 54 1:00 p.m. 51 51 2:00 p.m. 43 44 3:00 p.m. 40 45 5:00 p.m. 47 47 7:00 p.m. 44 44 8:30 p.m. 66 66 During this period, the air temperature varied from 14 to 31°C in the Open and from 15 to 32°C behind the wind-break; the wind velocity from zero to 6 kilometers per hour in the Open, and zero to 2.5 kilometers per hour behind the wind-breaks. Though wind velocities up to 11 kilometers 43 per hour were recorded in the Open (3 kilometers per.hour behind the wind-break) on June 16, the relative humidity behind the wind-break remained about the same as in the Open. Moisture Tension Inside the Leaf Leaf water tension was measured on July 16 (Replica- tion II) and July 20 (Replication III) from sunrise to sun- set and on July 21 (all Replications) from about 12 noon to 4:30 p.m. Air temperature and exact time were recorded as soon as a leaf was cut. The solar radiation values at these points in time were Obtained from the Michigan State Uni- versity solar radiation record maintained by the Department Of Agricultural Engineering. Wind velocity and relative humidity were recorded at the beginning and end Of each set Of Observations and the two readings averaged to give the mean values for the duration Of the set of tension measure- ments. TO avoid diurnal variations in leaf water tension, the measurements on July 21 were taken between noon and 4:30 p.m. - a plateau for leaf water tension during the day, as established from observations on the 16th, and 20th Of July. Air temperature during the Observations varied from 30 to 33°C in the Open and 31 to 35°C behind the wind- breaks; wind velocity from 8 to 10 kilometers per hour in the Open and 1.5 to 4 kilometers per hour behind the wind- breaks; relative humidity from 47 tO 52 per cent. There was no consistent pattern between wind protection and rela- tive humidity. Solar radiation varied rapidly from 0.80 44 45 to 2.78 millivolts due tO changing cloud pattern. The soil moisture tension under irrigation (both with and without mulch) was less than .25 atmospheres; without irrigation but with mulch it ranged from .25 tO .5 atmospheres; and without both irrigation and mulch it varied from .25 to 1 atmosphere. One high ground plot recorded 6 atmospheres. Wind protection had no effect on soil moisture tension. The mean leaf water tension values Observed are given below: NO irri- NO irri- gation, _gation, Irrigation, Irrigation no mulch mulch no mulch + mulch NO wind protection 13.7 13.0 12.1 11.9 Wind protection 13.6 12.8 12.4 11.8 The data indicate that on the day Of Observation, wind veloci- ties up to 10 kilometers per hour did not affect the leaf water tension. Though the mean tension in the unirrigated and unmulched plots was about 2 atmospheres higher as com- pared tO the irrigated and mulched, the difference may well be within the normal range Of variation. Moreover, the significance Of this magnitude Of dif- ference in leaf tension to the growth Of black walnut in its third growing season is not known. Diurnal Variation in Leaf Water Tension: During the initial stages Of these preliminary investigations, considerable 46 variation was Observed in the leaf water tension values during the day. TO detect a pattern in this variation, Observations were taken on the same.plants at 2 hour in- tervals from 7:00 a.m. tO 9:00 p.m. on July 16 (Replica- tion II) and July 20 (Replication III). The average water tension in the leaves during the different time periods on July 16 are_given below. Also shown are the average values for air temperature, relative humidity, and solar radiation. Time Leaf water Mean Mean air Mean solar Interval tension relative temperature radiation (atmospheres) humidity (°C) (millivolts) (%) 7:00 tO 7:38 a.m. 0.4 90 22 0.41 9:35 to 10:21 a.m. 10.1 69 30 1.54 11:10 to 11:45 a.m. 11.2 65 32 2.04 1:22 to 2:00 p.m. 12.4 54 34 2.00 3:08 to 3:39 p.m. 12.4 50 33 1.29 5:09 to 5:40 p.m. 10.4 54 31 0.80 7:11 tO 7:43 p.m. 7.0 65 31 0.11 8:43 to 8:58 p.m. 2.4 79 27 0.00 47 There is a sharp increase in leaf water tension from about 7:30 a.m. to about 10:30 a.m. (Figure 8) along with an increase in solar radiation and air temperature, and a decrease in relative humidity. The highest tension is reached when solar radiation and air temperature are at their highest and relative humidity is lowest. Though solar radiation falls to about half the daily maximum after 3 p.m., leaf water tension still remains high, along with a high air temperature and a low relative humidity. It drOps abruptly to 2.4 atmospheres around 9 p.m., when solar radiation is reduced to zero, air temperature to 27°C, and relative humidity rises to 79 per cent. The above course Of events would appear to indicate that though solar radiation may be the dominant factor determining leaf water tension in the morning and the even- ing due to its effect on the Opening and closing Of stomata, during the mid-day period leaf water tension is more re— sponsive to changes in air temperature and relative humidity. TO speculate on the extent tO which wind-breaks may decrease leaf water tension by reducing wind velocity, one must consider that wind-breaks also increase air tempera- ture, and their effect on leaf water tension as reflecting plant water stress, would have tO be a resultant Of two forces: an increase due to increased air temperature and a decrease (assumed) due to a reduction in wind velocity. 48 : -9O 12--2 n '80 30- -70 10 4 3 H g 0 -r-l '60 o O 8 . o ~ ~ 820:50 Cl 1‘ :5 O u 'r-l (U P u 6 0.1.3 g -40 "0 s T o It ‘\ E. '30 4 - 10' -20 ‘A ll 2 -I ~10 o L 7 ll 1 3 5 7 9 O D Time of the Day Plant Water Tension, Atms. Relative Humidity, % 13 Solar Radiation, Millivolts (3 Temperature, °C Figure 8. Diurnal variation in leaf water tension of black walnut in the second growing season after out— planting as 1—0, and in air temperature, relative humidity, and solar radiation. Measured July 16, 1968 at the Tree Research Center. Effects Of the Treatments on Soil Mineral Nutrient Elements Irrigation and mulching significantly affected the level Of exchangeable K at the 15 cms. depth Of soil. None Of the treatments applied had any influence on the mineral nutrient status Of the soil at the 30 cms. depth. Irrigation: As indicated by the data given below, irri- _gation significantly decreased (1% level) exchangeable K at the 15 cms. depth (Appendix III): Replication Mean exchangeable K (kilograms per hectare) Unirrigated "irrigated I 184 115 II 143 124 III 163 127 IV 237 197 V 181 136 Mean 182 140 The above means are based on unmulched plots only as mulch- ing influenced exchangeable K. The data for wind and fer- tilizer treatments have been combined since these had nO effect on exchangeable K. The decrease in K, with irrigation, 49 50 can be explained by increased leaching from the sandy soil Of the experimental area. Mulching: In conformity with previous findings (ROBINSON and HOSEGOOD, 1965; TUKEY and SCHOFF, 1963), mulching sig- nificantly increased exchangeable K at the 15 cms. depth (1% level). The fresh-wood mulch was probably the source of some Of this potassium. The increase is evident from the following values Of mean exchangeable K (kilograms per hectare) for the mulched and unmulched plots (Appendix IV): Unmulched Mulched I 170 235 II 127 167 III 97 192 IV 172 280 V 121 215 Average ' 137 218 The above means are based on combined date for fertilizer and wind treatments as neither Of these treatments affected the K content Of the soil. This mulch-induced increase in exchangeable K was significantly reduced by irrigation (5% level) as indicated below: 51 Mean exchangeable K (kilograms per hectare) Unmulched Mulched Unirrigated 137 218 Irrigated 121 168 This effect would appear tO follow from the separate effects Of mulching and irrigation on exchangeable K described al- ready: the former tending to increase it, the latter to scale it down. Fertilizer Application in PlaStic Sacks: Except for a greener foliage color on the fertilized plots, there did not appear to be much improvement in the fertility level as a result Of fertilizer treatments. The following check was applied to find out how much fertilizer had been re- leased from the plastic sacks at the end Of the first grow- ing season. The extent Of nutrient leaching from the fer- tilizer packets was measured in an adjoining experiment with tulip poplar seedlings established at the same time. In November 1967 soil was carefully excavated tO expose a column Of soil, about 15 cms. in diameter, with the dead plant in its center. The fertilizer packets were thus ex- posed, wedged at the periphery of the soil columns. Soil samples were taken from the face Of the column on which the fertilizer packet was found. The samples were taken in 7 cms. layers, starting from the tOp Of the columns, 52 and going 7 cms. below the packet. The soil immediately in contact with the packet was marked as such. For each Of the above points, an adjacent unfertilized planting point, identical in all the other treatments applied, was sampled in exactly the same manner as the fertilized plant- ing point. The results Of soil analyses Of these samples for P, K, and N, are given at Appendix V, VI, and VII, respec- tively. The data indicate that in only two Of the five packets had some fertilizer been released from the packets during the first growing season. It was also Observed that though the fertilizer inside the packets was moist, it had not lost its granular appearance and there was no evidence Of a slurry being formed which could have escaped from the packets through the pin holes. As an additional check, the packets were oven-dried for 24 hours, allowed tO reach equilibrium with the atmos- phere for four days, and then weighed. These weights were compared with the mean weight Of the remaining 120 packets out Of the lot used in the experiment. The results are given below: Mean dry weight unused packets (gms) 56.4 i 1.3 Weight (dry) Of five packets buried in the soil for one growing season (gms.) l. 53 2. 55 3. 58 4. 58 5. 55 53 These figures support a conclusion from soil analyses and visual Observation Of the packets: that there was only a small amount Of nutrients released from the packets during the first growing season. Since, as shown in the next section, fertilization significantly increased foliar nu- trient content, the lack Of weight loss from gravimetric measurements may have been the result Of water Of hydration gain during field weathering. Effects Of the Treatments on Foliar Mineral Nutrient Elements Foliar analysis was employed during the first (1967) and second (1968) growing seasons to assess the mineral nutrition level Of the plants subjected to the various treatments. First Growing Season Response On August 20, 1967, two entire leaves were plucked from each plant and the collection bulked for the three trees comprising each treatment. The foliar samples were immediately placed in an oven at 70°C and dried for 24 hours, and then ground in a Wiley mill. The analyses were performed at the Michigan State-University's Horticulture .Department lab using the Kjeldahl method for N determination, flame photometer for K, and spectroscope Of Na, Ca, Mg, Mn, Fe, Cu, B, Zn, and A1. The analyses indicated significant effects Of irrigation and fertilizer application on the foliar mineral nutrient status Of the plants. Irrigation: The irrigated plants had significantly higher foliar concentrations Of P, and K, and significantly lower foliar concentrations Of Ca and Mg. The above Observations are in conformity with the established views on the subject. 54 55 Thus Hibbard (1959) found that peaches and apples growing under moisture stress are unable to absorb P and K readily, and Cannell et al. (1959) Observed higher concentration5* of Ca and Mg in the leaves Of celery subjected to moisture stress. P foliar concentration: The following mean values for foliar P concentration (per cent) show its significant increase under irrigation (5% level) (Appendix VIII): Replication Unirrigated Irrigated I .183 .212 II .165 .212 III .195 .190 IV .173 .221 V .179 .183 Average .179 .203 The above means are for unmulched plots, combining the data for wind and fertilizer treatments. A similar in- crease occurred in mulched plots as well -- from .192 to .213 per cent. K foliar concentration: Irrigation significantly increased K foliar concentration, as reflected in the data given be- low (1% level) (Appendix IX): 56 K foliar concentration (%) Replication Unirrigatea Irrigated I .42 ~92 II .42 .67 III .52 .90 IV .76 1.06 V .72 .54 Average :57 ‘83 Since K foliar concentration is influenced by interactions involving almost all the treatments applied, the above means are based on combined data for wind treatments alone. Except for an unusually low value for the irrigated plots Of Replication V, the comparisons all indicate considerable increases in the concentration Of foliar K in response to irrigation. Mg foliar concentration: Irrigation significantly decreased Mg foliar concentration (1% level). The effect was modi- fied by the presence or absence Of fertilizer (1% level); though irrigation reduced the foliar Mg concentration Of both the fertilized as well as unfertilized plants, the reduction was much more pronounced for the fertilized plants (.49 to 37%) as compared to the unfertilized (.44 to .41). (Appendix X for complete data.) 57 Ca foliar concentration: Irrigation significantly decreased Ca foliar concentration (5% level), the mean of irrigated plants being 1.69 per cent as against 1.82 per cent for the unirrigated (Appendix XI for complete data). Fertilizer application: Fertilizer application signifi- cantly increased N foliar concentration (1% level) as evi- dent from the data given below (Appendix XII): Mean foliar N (%) Replication Unfertilized Fertilized I 2.29 2.59 II 2.41 2.54 III 2.25 2.54 IV 2.36 2.54 V 2.46 2.22 Average 2.35 2.49 The above means are based on plots afforded wind treatments; the irrigated and mulched plots have not been included due tO the significant interactions Of these treat- ments with fertilizer application. The fertilizer-induced increase in N foliar concen- tration appeared to be enhanced when irrigation was com- bined with fertilizer application (5% level). Fertilizer application increased the mean foliar concentration Of un- irrigated plants from 2.35 to 2.49 per cent and the increase for the irrigated plants was much higher -- from 2.16 to 58 2.56 per cent. These means are based on combined data for plots under wind protection and no wind protection treat- ments. The increase in mean per cent foliar N concentration appeared to occur only in the unmulched plots: (interac- tion mulching x fertilizer application significant at 1% level): whereas the mean foliar concentration Of the ir- rigated unmulched plots increased from 2.16 tO 2.56 per cent with fertilization, there was no increase in the case Of the irrigated mulched plots (2.33 for unfertilized, 2.37 for fertilized). Practical significance: Interesting though these statis- tical significances may be, it is possible that the only one which had practical significance on the nutritional status of black walnut in the first growing season was the irrigation-induced increase in K foliar concentration, taking the plants out Of the deficiency range almost to the verge Of the intermediate range, according to the stand- ard values for California walnut (Appendix XIII). The P and Mg levels remain in the normal range in spite Of the slight responses tO the applied treatments, the N level stays in the intermediate range even after the slight increase from the slow-release packets. Second Growing Season Response On July 17, 1968, leaflets were collected from the three trees comprising each treatment and the collection 59 for each treatment bulked. Foliar samples were placed in an oven at 70°C, and after drying and grinding, the sam- ples were analyzed for N and K in the same manner as in 1967. K foliar concentration: Mulching almost doubled the K foliar concentration, taking the plants out Of the defi- ciency range into the normal range for K nutrition. The magnitude Of increase is brought out below (Appendix XIV for complete data): Mean foliar K concentration (%) Replication Unmulched Mulched I 0.63 1.27 II 0.55 1.06 III 0.58 1.20 IV 0.82 1.36 v 0.62 1.12 Average 0:64 1'20 The above means are for unirrigated and unfertilized plants, combining the data for wind treatments. A similar, although smaller, increase occurred in the irrigated plants as well -- from 0.82 tO 1.16 per cent. As indicated below, fertilizer application signifi- cantly increased the foliar K concentration Of the unmulched plants but not that Of the mulched. (Interaction mulching x fertilizer application significant at 1% level): 60 Mean foliar K concentration (%) Unfertilized Fertilized Unmulched 0.64 0.87 Mulched 1.20 1.15 The above means are for unirrigated plants, combining the data for the wind treatments. N Foliar Concentration: Fertilizer application significantly increased N foliar concentration (1% level). The magnitude Of increase is brought out below (for complete data see Ap- pendix XV): Mean foliar concentration (%) Replication Unfertilized Fertilized I 3.10 3°35 II 2.85 3.10 III 2.57 3.10 IV 2.87 3.12 v 2.59 2.91 Average 2°80 3’12 Since nO other treatment significantly influenced N foliar concentration, the above means are based on the combined data for all the treatments. 61 First Growing Season's Growth Responses tO the Treatments Applied Leaf Area Leaf area was measured in the first growing season by systematically collecting a 10 percent random sample Of leaflets and then applying a previously determined regres- sion Of dry weight tO leaf area. Details Of the two pro- cedures are as follows: A leaflet was plucked from the middle of the rachis Of every alternate leaf Of the plant in the center Of the group Of three plants representing each treatment. The leaflets were traced on paper and their leaf areas measured with a planimeter. Their oven-dry weight was then deter- mined after drying for 24 hours at 70°C. (Appendix XVI.) The regression Of leaf area on oven-dry weight was signif— icant (1% level) with 99.7 percent Of the variation in leaf area ascribable tO variation in oven-dry weight. A 10 percent random sample Of the leaflets was taken from each plant in the following manner: The total number Of leaves and leaflets were counted on each plant. All the leaves on a plant were given serial numbers, starting from below, and lots were drawn from these numbers. As a particular number came up, 62 one leaflet was plucked from this leaf. The position Of this leaflet on the rachis was determined by drawing lots from another set Of numbers which represented the total number Of leaflets on this particular rachis. As a number came up from this set, the leaflet to be plucked was spot— ted by counting from the lowermost leaflet, in counter- clockwise direction. The collection from the group Of three plants rep- resenting a treatment was bulked and its oven-dry weight determined. The oven-dry weight was converted to leaf area using the regression equation already develOped (Y = 0.5535 + 171.8765 X). This value was then converted to leaf area Of the group Of three plants by multiplying it with the factor: total number Of leaflets on the plants/number Of leaflets plucked from them. The treatment-wise mean leaf areas per plant are given in Appendix XVII. Of the treatments applied, only mulching increased leaf area significantly (1% level) dur— ing the first growing season. Owing to significant inter- actions with irrigation and wind protection,the datacmupage 63 have been taken only from unirrigated plots, not protected from wind. The data from fertilized and unfertilized plots have been combined as neither the main effect of fertilizer application nor its interaction influenced leaf area significantly. 63 Replication Mean leaf area per plant, cm2 Unmulched Mulched I 1368 1502 II 2208 1988 III 1532 2114 IV 2120 2725 V 1595 2436 Average 1765 2153 The following figures would appear tO indicate that though both mulching and irrigation, separately, increased leaf area, irrigating the mulched plots did not increase the leaf area further (interaction mulching x irrigation significant at 1% level). Mean leaf area per plant, cm2 Wind_protection NO wind protection Unmulched Mulched Unmulched Mulched Unirrigated 1843 2947 1765 2153 Irrigated 2510 2519 2370 2236 The above means represent combined data for fertilized and unfertilized plots. 64 The effect Of mulching in increasing leaf area was considerably enhanced when wind protection was also provid- ed. This mulching x wind protection interaction (signif- icant at 5% level) is brought out below: Mean leaf area per plant, cm2 Unmulched Mulched NO wind protection 1765 2153 Wind protection 1843 2947 The above means are based on the unirrigated fertilized and unfertilized plots. Though wind protection, without mulch- ing, did not increase leaf area, and mulching alone in- creased it by only 22 percent, mulching combined with wind protection raised it by 67 percent. 65 Second Year's Growth Responses to the Treatments Applied Leaf Area During 1968, leaf area was measured in a somewhat less tedious manner as follows: A leaflet was plucked from the middle of the rachis of the leaf in the center of the crown of the best plant out of the three comprising each treatment. Its leaf area was measured (by planimeter); as were its length (L), and maximum width (W). The length and maximum width were mul- tiplied to give the value L X W. The regression of leaf area on the value L X W was significant (1% level), with 95.7 percent Of the variation in leaf area ascribable to variation in the value L X W. The total number of leaflets were counted on the best Of the three trees in each treatment. Four Of the entire leaves from each of these plants were picked out at random by drawing lots and the central 3 to 5 leaflets on one side of the rachis of each of these leaves measured for length, and maximum width, making up a 10 percent sample Of the leaflets so measured. From these measurements, the length and maximum width were worked out for the mean leaf— let Of the tree representing each treatment. The product L X W for the mean leaflet was converted to the area of the mean leaflet representing each treatment using the regres- sion equation developed already (Y = 1.237 + .6502 X). 66 The area Of the mean leaflet for each tree was multiplied by the total number Of leaflets on the tree to give its total leaf area (Appendix XVIII). Wind protection (Figure 9) and mulching signif- icantly increased leaf area (1% level), as indicated by the following means based on the combined data for the fertilizer and irrigation treatments: Mean leaf area Of the bestzplant Replication in the treatment, cm NO mulch Mulch, NO mulch, Mulch + no wind no wind wind wind protection protection protection protection I 1686 1944 2576 3094 II 2419 2301 3359 4155 III 2048 2481 3960 5944 IV 2367 2612 4356 5602 V 3134 2904 4038 4949 Average 2331 2448 3658 4749 The interaction Of wind protection x mulching was significant (1% level), and is evident from the data given above: whereas mulching alone increased leaf area only by 5 percent, and wind protection alone by 57 percent, both combined more than doubled it--from 2331 tO 4749cm2. Figure 9. 67 "film-ru“ *- m a Field planted walnuts in second growing season without wind protection (top) and in the shel— ter of ‘wind breaks (bottom). Wind protection significantly increased leaf area, height, and diameter. 68 Height Growth Total height: The total terminal height at the middle of the second growing season (measured on July 22, 1968) was significantly increased (1% level) by mulching, as well as wind protection (Figure 9); the interactions of wind pro- tection with mulching and irrigation with mulching were also significant (1% and 5% levels, respectively). These observations are brought out in Table 7. When mulching and wind protection are applied alone, in the absence of irri- gation, each caused a 7 percent increase in total terminal height. But when applied together, the combined effect is reflected in a 30 percent increase. The interaction of mulching with irrigation is illustrated by the data below: Mean total terminal height, cms Unmulched Mulched Unirrigated 47 61 Irrigated 54 57 Both irrigation as well as mulching increased total terminal height but irrigating the mulched plots did not increase their height further. 69 muoam omNHHflpHmmco pom omNHHHuHmm How opmo omcflnaoo co comma mcmoz H nm em am we me me we we mmmnm>¢ me be me om me me mm we > no am pm we we em me he >H ow om mm me we mm me me HHH mm be 5m we om om me we HH ow mm mm me we mm me ow H aoasfi noaoa QOHSE soasfi soasz oz coasz oz boas: oz boas: oz ompmmHHHH omummfluuflcb omummHHHH omummHHHHQD coepomuoum UGflz coeuomuonm UQHB oz coauMOHHmmm mEo .wcmwmc Hmcflfinmp Hmuop Home: Amumo mumHmEoo How xHx xflocmmmd momv Awmma .Nm NHSH panammosv mcfipcmambso mcHBOHHow common mcfl3onm Uncoom can mo maooflfi map moanso pscama Moman mo #cmflm: Hmcflfiump Hapop mcp so GOHpomuoum ©GH3 Spa; mcflzoasa mo chHwomumpcfl map Ucm .mcHSOHSE .cOHpomponm UGHB mo pommmm .m magma 70 Current year's terminal height growth: The response of the current years' (1968) terminal growth to the applied treat- ments was similar to that of total height growth. Signif- icant effects were obtained with wind protection and mulch- ing (1% level). The interaction irrigation x mulching was significant (1% level) and that of mulching x wind protec- tion on the border of significance (5% level) (Table 8). The interaction mulching x irrigation is illustrated by the following data for the wind protected plots, combin— ing the data for the fertilizer treatments: Mean current year's terminal height growth, cms Unmulched Mulched Unirrigated 22 37 Irrigated 28 31 As observed for total height growth, current year's height growth of the mulched plots does not seem to in- crease when irrigation was combined with mulching. Diameter Growth Diameter at 2.5 cms. above ground level: As measured on July 22, 1968, during the middle of the second growing season after outplanting, diameter at 2.5 cms. above ground level was significantly increased by mulching, and wind 71 muoam UmmflaflpuGMCS Ucm UmNHHHunmm How mumo UocHQEoo co comma mono: a an mm mm mm mm Hm mm ma mmmum>¢ ma om we mm ma ma mm ea > mm mm mm mm mm mm mm ma >H mm Hm mm ea mm ea om ma HHH mm om mm Hm om mm Hm ea HH mm mm mm mm mm NH ma ma H QOHSE coasa QOHDE soaoa zoaoz oz zofioz oz zozoz oz zoasz oz omgmmfinuH ompomfluuflcb UmammHHuH omummfinuflcb coapompoum UQHB cofluomponm UGH3 oz coepMOHHmom mEo .SpBOHm pnmflmn Hmcfifiuoo m.Hmo> #coHHso Hammz Amumo mpmamfioo How xx xflpcomm¢ ommv Ammma ~mm Mash woMSmmofiv uncHMB Moman mcflpcmHm Hmpmm GOmmmm mcfl3oum ocoomm mcu mcfluso cuzoum unmflma HmcHEHop Ammmav m.Hmm> ucomnso ms» co mcHSOHSE paw cowbmmfluufl mo coeuomumocfl map Ucm.mcH£OHsE .COHbomuoum UQHB mo poommm .m manme 72 protection (1% level), their combination being synergistic (1% level) (Table 9). Though irrigation and mulching, separately, appeared to increase diameter growth, irrigating the mulched plots did not further increase the diameter growth. (Interaction of mulching and irrigation significant at 5% level.) Diameter at the Base of the Current Year's (1968) Terminal ghggt: Diameter at the base of the current year's terminal shoot (Appendix XXII) is significantly increased by mulch— ing, wind protection, and fertilizer application (1% level), the increase in mean diameter is about 1.0 mm in all cases. A similar irrigation x mulching interaction as for diameter growth at 2.5 cms. above ground level, was also noticed. As evident from the following figures, though mulching and irrigation, separately, increased diameter, no further increase occurred when mulching was combined with irrigation: Mean diameter at the base of the current year's shoot, cms Unmulched Mulched Unirrigated 0.76 0.98 Irrigated 0.84 0.92 73 mDOHm wouflafluummcs paw pmuflaflunmm MOM dump oocflnfioo co comma mcmoz H mH.H NH.H mm.H mm.o mo.H mo.a oo.H no.0 mmmum>¢ oo.H oa.H ow.H mo.H oo.H OH.H OH.H mm.o > om.H om.H om.H om.o oa.a om.a mo.H mo.H >H mm.H OH.H om.a mm.o oo.H mm.o oo.H mm.o HHH mH.H mo.a om.H mo.H oo.H oo.H mm.o oo.a HH ma.a mo.a ma.a oo.H oo.a om.o om.o om.o H noasfi coasfi coasfi coasfi zoasz oz boas: oz noes: oz zoasz oz UmbmmmuHH ompmmHHHHcD UopmmHHMH Umummflunflab coauoououm UGHS coauomuoum UGHB oz coapmoflammm mEo .Ho>oH ocsoum m>onw .mEo m.m pm HmmeMHo acmmz Ampmo mumamfioo How Hxx xflpcmmmd wmmv Ammma .NN Mann monommwfiv mcflpcmHmpso Hmumm GOmmmm mcHBOHm Uzoomm mDH 2H .uscam3 MomHQ “Ho>ma ocsoum m>onm .mEo m.m um HmmeMHo co mcflnoasfi paw coflpmmflnnfl mo cofipomumpcfl paw .mcficoasfi .coapomuoum UGHS mo pommmm .a magma PLANTING CONTAINER-RAISED BLACK WALNUT Silvicultural experience in the planting of hard- woods has generally shown a direct correlation between intensive planting care and the initial success of planta- tions. This is particularly true with tap rooted species such as oak and walnut. There is also limited research data to show that initial black walnut plantation success is directly related to a minimum disturbance to the root system (SEIDEL, 1961). Walnut develops a deep, fleshy tap root during the first growing season (Figure 10). This tap root is sur- rounded by a dense fibrous root system which occupies a rather considerable mass of soil the first season and may extend 45 cms. below the surface. When stock is raised in the nursery as 1-0, it already has a root system partic— ularly unadapted to the bare-rooted lifting and planting methods which characterize standard forestry practice. General recommendations for planting nut-seeds have favored direct seeding, particularly because of the advantage of not having to disturb the root system. Current recommenda- tions for black walnut planting (ERDMANN, 1966) mention that direct seeding may be successful if the several site 74 75 Figure 10. Root system of 3—month old black walnut raised in soil mix in cardboard milk containers. 76 and biological limitations to this approach, i.e., rodents, frost, poor germination, etc. could be controlled. At the beginning of this study we thought that a method of container planting, such as has been successfully used for landscape and horticultural plants should be well suited to this species. The obvious increased cost of this approach is not a serious problem. The long term objective of walnut planting is to produce single high quality trees in 40-60 years which may have a stumpage value in excess of $500 each. Looking at the planting problem in this light, it would be better for a farmer to grow 25 carefully tended trees to maturity than to grow 25 acres of low grade walnut firewood in the same rotation--which incidentally is the future of many field planted walnut groves which have had no cultural care since planting. The research and development of a "best" planting container was not an objective of this research. However, we settled on two types of planting containers which showed promise in the hOpe that by getting a head start with con— tainer grown trees growing in research plots we might fur- ther the establishment of potentially valuable trees. The types of containers we used are: l. BR—8 blocks (supplied by American Can Company, Neenah, Wisc.) made of wood pulp fibres with certain additives to prevent rot (Figure 11). The blocks were rectangular - about 20 cms. 77 Figure 11. Field planting of greenhouse raised black wal- nut, six weeks from seed, in BR-8 blocks. Top left: BR—8 blocks inside cardboard milk container. Top right: container removed preparatory to planting, note vigorous roots coming right down to the bottom. Bottom left: BR—8 block being carefully planted to prevent any disturbance to the root system. Bottom right: Final stage in planting. Soil from sides of hole will be carefully packed around block using tiling spade. Top soil will be packed to cover the top of container. 78 long and 9x9 cms. at the top and bottom ends-- and were inserted into 1/2 gallon waxed card- board milk containers. Papier—mache plantable containers (Figure 12). (supplied by Pullen Pot Co., New Iberia, La.) about 25 cms. long and with tOp and bottom inside diameters of about 9 and 6 cms., re- spectively. The pots were filled with a soil mix containing peat, Turface, and loam in a 1:1:1 ratio. 79 «.9 V ‘ ‘ ' . d I - -- - ‘ .4 . _Mo,--~ _ . not 1“.» W“ - ~— -—— Figure 12. Three—week old black walnut raised in soil mix in papier—mache plantable pots (left). Plant removed to show the root system (right). 8O Germination A pre—requisite for successful container planting is prompt seed germination during the first week of April so that the stock in containers is about three—six weeks old and ready for planting when all danger of frost is over. Experience during 1967 had suggested that stratifi- cation at constant temperature in a cold room resulted in delayed germination which continued till October. Needed was a method which could accelerate germination, concen— trating it in the first few days of April. With this end in View, the following germination test was conducted: Nuts were collected from a single tree in Kellogg Forest in October 1967. Half of them were husked and half left unhusked. Each of the two lots were further subdivided into two: One was stratified in moist vermiculite in the cold room at about 4°C, and the other stratified outdoors in a nursery bed, covering with about 10 cms. of the sandy soil. On May 1, 1968, all the nuts were removed from stratification and planted immediately in the greenhouse in vermiculite after subjecting each of the above mentioned categories to the following treatments: 81 T — Control T2 — Gibberellic acid 200 p.p.m. soak for 12 hours T3 - Thiourea .5% soak for 12 hours T4 - Thiourea 1% soak for 12 hours The experiment was thus conducted in the split—split plot design, with husking and not husking as the first main split; field and room stratification as the second main split; and GA and thiourea soaking as subplot treatments in. the second main split. Four replications were provided and eight nuts were allotted to each subplot treatment. The progress of germination is given in Table 10. Thus room stratification proved to be the most inferior method and field stratification of husked nuts better than that of unhusked, with the subplot treatments making no difference to germination. Similar results were also obtained by Chase (1947) who concluded that the germination of black walnut nuts stratified at controlled temperature (in sand) was signif- icantly lower than that of the nuts planted in fall or stratified outdoors. It may be that some inhibitor leaks out of the nuts during field stratification, or that alter- nating temperature outdoors has a stimulating effect on germination. The better germination with husk removal would seem to point to the possible role of an inhibitor. The above trial suggests the following time table of operations for container stock planting in Michigan: 82 mzsoa NH Hem zoom NH moHSOH£Ee muooc NH Mom MMOm wm. mmHSOHQB m musos NH Mow Mm0m .E.m.m OON oHom oHHHmeQQHUN ON CO H u OH 0 o o H N N H o o o H N m m m m Hmuoa o o o o H N o o o o H N H N N o NH mm: o o o H H o H o o o o o w m m m w mm: HHH o o o o H N m m H H H H m m m o HMDOB o o o o H H N m H H o H o o N H NH mm: o o o o o H H N o o H o m m w m w mm: HHH o o o o w e e N o N o o m m m m Hmuoa o o o o N m m N o N o o m N N H NH was 0 o o o N H H o o o o o N w m N e was HH 0 o o o m H H w o o o H H m m m HMDOB o o o o m o H m o o o H o H o N NH mm: o o o o o H o H o o o o H w m m e an: H AUwDQme m mo #50 UmDMCHEHom wpsc MO HQQEDGV B me NB HE we mB NB HE we mB NB HB weB mma NN H UoHMHuoHDm UoHMHuoHum pwHMHumubm UwHMHpmupw Boom onHm zoom UHmHm memHV ooxmsscb ooxmzm ouwo QOHumoHHmom mHGmEDmmHH msoHHm> Moons EOHDMGHEHmm DDGHMB MOMHQ mo mmmumozm .OH OHQMB 83 Collect nuts as soon as ripe (about mid—October) Husk and stratify outdoors, immediately, cover— ing with 10—15 cms. of sand Remove seed from stratification on April 1 and plant in green house in soil, sand, or vermic— ulite Pot as the seedlings emerge. 84 Comparison of Planting Container Stock, 1-0 Nursery Stock, and Germinating Nuts On April 10, fifty germinating nuts which had just split (seed source 5748, Kellogg Forest) were planted in each of the 2 types of containers. An equal number were held in the cold room for direct seeding. For use with the BR—8 blocks, the nuts had to be just split, without the radical protruding so that it could work itself into the block material, otherwise we encountered difficulty in getting an adequate contact between the root and the pulp. A depression was made in the blocks, just large enough to accommodate the nut which was then covered with vermiculite. The containers were kept in the greenhouse and watered as necessary to keep the planting medium continuously moist. From May 10 until outplanting, the stock was exposed to full sun on every sunny day in the shelter of the green— house building. The stock was outplanted on May 21 in moist soil. Preplanting weed control (amitrol T foliar spray) had been applied to the planting site on May 1. Wind protection was provided by parallel wind-breaks of snow fencing erected 10 feet apart against the predominant wind direction. The comparison was laid out in the randomized complete block 85 design with 6 replications and eight trees spaced 60 x 60 cms. allotted to each of the four treatments: papier—mache containers, BR-8 blocks, l—0 nursery stock, and germinating nuts planted directly in the soil. No irrigation has been necessary since planting because of regular rains. A post— planting amitrol T spray was applied on June 15. All plants were protected with covering pails during the spraying operation. 28 grams of 8:4:8 NPK liquid fertilizer was applied to each tree in 800 c.c. of water on June 15 and August 8. Present status: It is too early yet to make a detailed comparison of the methods tried. A visual rating of tree vigor about 3 months after planting would be: 1. Direct seeding 2. BR-8 blocks 3. Papier-mache containers 4. 1—0 stock Direct planting of germinating nuts have produced plants which appear to be the most vigorous probably because their root systems are in a better position to absorb the added fertilizer. The same would appear to hold for the stock in BR—8 blocks. Even though the plants in papier—mache con— tainers have a well developed root system, it emerges from the container 25 cms. below the soil surface and is thus not able to utilize the applied fertilizer most efficiently. 86 The 1—0 stock has probably not yet developed an extensive root system capable of absorbing the applied fertilizer efficiently. SUMMARY AND CONCLUSIONS Wind protection and mulching significantly increased the early growth of black walnut. The treatments were syner— gistic when applied together. A positive response to these treatments was first detected in leaf area measured at the close of the first growing season after outplanting of 1—0 stock. On July 22, 1968, towards the middle of the second growing season, the response could also be detected in total height growth, current year's terminal height growth, dia- meter at 2.5 cms. above the ground level, and diameter at the base of the current year's shoot. During the second growing season, wind protection combined with mulching, increased leaf area by 100 percent, total height by 31 percent, height of the current year's terminal shoot by 85 percent, diameter at 2.5 cms. from the ground level by 20 percent, and diameter at the base of the current year's terminal shoot by 25 percent. Though the main effect of irrigation did not signi— ficantly influence any of the growth parameters measured, its interaction with mulching was invariably significant for each of them. It appears that irrigation and mulching separately, increased growth as reflected in the parameters measured; in combination, however, the increase did not 87 1 1 ! 88 exceed that with mulching alone. The reason for not detect— ing the significance of the main effect of irrigation may be the design of the experiment adopted, with irrigation as a second split main plot treatment instead of a sub- plot treatment. The only visible growth response to fertilizer ap— plication was its significant increase of the mean stem diameter at the base of the second growing season's terminal shoot from 0.8 to 0.9 cms. and a marked improvement in foli- age color. Fertilizer uptake from the sacks in any quantity, however, only started during the second growing season and it can be expected that the effects of better nutrition will be even more pronounced in the following growing sea- son. Of the possible mechanisms by which mulching could increase vegetative growth, the one that stands out most prominently is its effect on the K nutritional status of the plants. The plants in the experimental area were defi- cient in K and mulching apparently corrected this deficiency, as shown by the doubling of foliar K concentration with mulching. Irrigation also increased foliar K concentration but brought the plants only up to the verge of the inter— mediate range, for K nutrition. Mulching also maintained the 0—30 cms. soil layer at a slightly higher moisture content (12—21 percent by volume during the 1967 growing season as compared to the 89 control (ll—l9 percent for most of the growing season, dropping to 8 to 9 percent for only two weeks in August). It seems unlikely that soil moisture ever became limiting to the growth of black walnut even in the 0—30 cms. layer. Moreover, the roots must have reached the 30-60 cms. layer of soil within a short time after planting, and soil mois- ture in this soil layer was not influenced by any of the treatments applied. The above reasoning would appear to lead to the suggestion that the beneficial response with mulching is probably not primarily due to its effect on soil moisture conservation. Mulching decreased soil tem- perature at 7 cms. depth during the heat of the day. But high summer soil temperatures are not a factor limiting plant growth in Michigan. The beneficial role of wind protection in increasing growth is more difficult to explain. Wind protection not only considerably increased growth by itself, but increased the beneficial reSponse to mulching. In the absence of wind protection, the response to mulching was barely de— tectable, but the two combined acted synergistically under the conditions of this experiment. In this experiment, wind could conceivably increase vegetative growth through the following mechanisms: 1. Both air and surface soil temperatures were higher in the shelter of the wind-breaks for most of the day as compared to the open. 90 Besides increasing plant growth throughout the growing season, this effect on temperature has considerable bearing on the incidence of early spring frost. Following a frost on May 18, 1968, for example, the plants in the shelter of the wind—breaks were not affected whereas all the leaves on the plants in the open were killed and the trees were set back in growth by two weeks. Considerable mechanical injury to the foliage (Figure 13) is a conspicuous effect of wind on the study site, especially during June and early July, when it is hard to find a single undamaged leaf on unprotected small trees. This could ad— versely affect leaf area thereby reducing vege- tative growth in general. Even though no soil moisture stress seems to have developed for black walnut during the per- iod of this study, it is possible that plant water stress did develop due to higher tran- spiration demand under high wind velocities. It could thus be argued that wind—breaks may have increased vegetative growth by reducing plant water stress during such periods due to their effect in reducing wind velocity. But in addition to decreasing wind velocity, wind— 91 4:50: :1150 =‘20123455‘ Figure 13. Walnut leaves from open grown trees (left) and in the shelter of wind break (right). Unpro- tected leaf shows serve mechanical injury. 92 breaks also increased temperature in their shel- ter, which would tend to increase plant water stress. So the net effect of wind-breaks on plant water stress at any time would depend upon the balance between the reduction in plant water stress due to decreased wind velocity, and its increase due to the higher temperatures behind the wind-breaks as compared to the Open. It was found that wind velocities up to 10 kil- ometers per hour did not increase plant water tension under the conditions of the investiga- tion. The above reasoning would appear to suggest that wind protection increased vegetative growth due to its ef- fect in increasing temperature, decreasing wind—caused mechanical injury, and probably also by reducing plant water stress on hot, dry, windy days. Though the main effect of irrigation was not signi- ficant, its interaction with mulching indicates that by it- self it did increase leaf area, height, and diameter. These increases could also be caused by an irrigation-induced im- provement in the K nutrition of the plants. Since irriga- tion combined with mulching did not improve the K status of the plants over mulching alone, the plant growth response to irrigation + mulching was not greater than to mulching alone. 93 In summary, the principle site improvement recom- mendations for field planted black walnut are: 1. Wind protection is essential for the vigorous early growth of black walnut on level, open field sites. 2. Where plants are deficient in K, favorable growth responses can be expected to the appli— cation of wood—chip mulch. 3. Wind protection and mulching are synergistic in their effect on plant growth and should be combined. 4. Some practical way should be found to insure adequate nutrition and correction of any nut— rient deficiencies during the first growing season. Perhaps some modification in the slow— release fertilizer packet may achieve this, or the periodic application of foliar or liquid fertilizer may be the answer. Though the investigations on planting stock raised in containers have not been pursued long enough to yield any definite conclusions, indications are that planting 3 to 6-week old stock with containers, immediately at the start of the frost-free period, is likely to increase growth due to the elimination of any damage whatsoever to the root system, an increase of the growing period by 3 to 6 weeks, and a better ability of the root system to absorb soil applied fertilizer during the first growing season after planting. LITERATURE C ITED LITERATURE CITED Bouyoucos, G. J. 1961. Soil moisture measurement improved. Agricultural Engineering 42:136—138. Cannel, G. H., K. B. Tyler, and C. W. Ashell. 1959. The effect of irrigation and fertilizer on yield, black heart, and nutrient uptake of celery. Am. Soc. Hort. Sci. Proc. 74:739-745. Chase, S. B. 1947. Eastern black walnut germination and seedbed studies. J. For. 45:661-668. Cliff, E. P. 1966. The increasing challenge of decreasing quality. In Black Walnut Culture. pp. l-3. North Central Forest Experiment Station. U.S.F.S. Carbon— dale, Ill. No series. 94 p. Duley, F. L. and L. L. Kelly. 1939. The effect of soil type, slope, and surface conditions on intake of water. Neb. Agric. Exp. Sta. Res. Bul. 112. 16p. Erdmann, G. G. 1966. Planting. In Black Walnut Culture. pp. 28-31. North Central Forest Experiment Station. U.S.F.S. Carbondale, I11. No series. 94p. Evans, H. J., and G. J. Sorger. 1966. The role of mineral nutrient elements with emphasis on the univalent cations. Ann. Rev. Plant Phys. 17:45—50. Finn, R. F. 1966. Mineral nutrition. In Black Walnut Culture. pp. 35-41. North Central Forest Experi- ment Station. U.S.F.S. Carbondale Ill. No. series. 94p. Finnell, H. H. 1928. Effect of wind on plant processes. J. Am. Soc. Agron. 20:206-1210. Hibbard, A. D. 1959. Leaf content of P and K under mois- ture stress. Am. Soc. Hort. Sci. Proc. 73:33—39. Jacks, G. V., W. D. Brind, and R. Smith. 1955. Mulching. Techn. Comm. No. 49 of the Commonwealth Bureau of Soil Science, England. 87p. 94 95 Jarvis, P. G., and M S. Jarvis. 1963. The water relations of tree seedlings. 1. Growth and water use in relation to soil water potential. Physiol. Plant. 16:215—235. Kenworthy, A. L. 1967. Plant analysis and interpretation of analysis for horticultural crops. In Soil Testing and Plant Analysis, Part II —- Plant Analy— sis. pp. 59—75. Soil Science Society of America. Khattak, G. M. 1965. Volume growth of 'shisham' (Dal- bergia sissoo Roxb.) under various regimes of ir— rigation. (Typewritten). Kohnke, H., and C. H. Werkhoven. 1963. Soil temperature and soil freezing as affected by an organic mulch. Soil Sci. Soc. Am. Proc. 27:13-17. Lemon, E. R. 1956. The potentialities for decreasing soil moisture evaporation. Soil Sci. Soc. Am. Proc. 20:120-125. Martin, E. V., and F. E. Clements. 1935. Studies on the effect of artificial wind on growth and transpira- tion of Helianthus annuus. Plant Physiol. 10:613- 636. Proebsting, E. L., and E. F. Serr. 1966. The edible nuts. In Nutrition of Fruit Crops. pp. 262-275. Horticul- tural Publications, Rutgers, the State University of New Brunswick. 888 p. Quigley, K. L., and R. D. Lindmark. 1966. Timber resources. In Black Walnut Culture. pp. 6-12. North Central Forest Experiment Station. U.S.F.S. Carbondale Ill. No series. 94p. Randall, C. E. 1967. Black Walnut-- Our vanishing money tree. American Forests 73 (10):l4-l7, 38—40. Reuther, W., T. W. Embleton, and W. W. Jones. 1958. Min- eral nutrition of tree crops. Plant Physiol. 9: 175-206. Robinson, J. B. D., and P. H. Hosegood. 1965. Effects of organic mulch on fertility of a latosolic coffee soil in Kenya. Expl. Agric. 1:67—80. Russell, J. C. 1939. The effect of surface cover on soil moisture losses by evaporation. Soil Sci. Soc. Am. Proc. 4:65—70. 96 Sands, K., and A. J. Rutter. 1959. Studies in the growth of young plants of Pinus sylvestris L. II. The re- lation of growth to soil water tension. Ann. Bot. N.S. 23 (90):269-284. Seidel, K. W. 1961. Seeded black walnut taller than planted walnut on Kansas spoil banks. Central States Forest Experiment Station. U.S.F.S. Sta. Note 148, 1p. Scolander, P. F., H. T. Hammel, E. D. Bradstreet, and E. A. Hemmingsen. 1965. Sap pressure in vascular plants. Science 148:339—345. Stanhill, G. 1957. The effect of differences in soil moisture status on plant growth. A review and analysis of soil moisture experiments. Soil Sci. 84:205-214. Tukey, R. B., and E. A. Schoff. 1963. Influence of dif— ferent mulching materials upon the soil environ- ment. Am. Soc. Hort. Sci. Proc. 82:68-76. Uriu, K. et a1. 1964. Cling peach irrigation. Calif. Agr. 18(7):lO-ll. Von Neirop and D. P. White. 1958. Evaluation of several organic mulch materials on a sandy loam forest nursery soil. J. For. 56:23-27. Wadsworth, R. M. 1959. An optimum wind speed for plant growth. Ann. Bot. N.S. 23:195—199. . 1960. The effect of artificial wind on the growth rate of plants in water culture. Ann. Bot. N.S. 24:200-211. White, D. P., and B. G. Ellis. 1965. Nature and action of slow release fertilizers as nutrient sources for forest tree seedlings. Quart. Bul. Mich. Agr. Exp. Sta. 47(4):606-614. Whitehead, F. H. 1963. The effect of exposure on growth and development. In The Water Relations of Plants. pp. 235-245. Blackwell Scientific Publications, London. 394p. Zarger, T. G. 1946. Mulching effects on the growth of grafted black walnut trees. Am. Soc. Hort. Sci. Proc. 47:178—180. APPENDICES 97 omnoHsz HE .coH#mmHHHH HH .coHuomuoum UCHZ H3 NM @cHQOHSE oz 02 .cngmmHHHH 02 OH .cOHuoououm chB 02 03 \d m.ON N.mH n.0N m.kH m.ON c.0N H.0N p.mH m .uoo e.mH a.mH m.mH m.eH m.mH m.oH m.NH m.eH GN nomm n.mH m.NH s.eH m.OH N.mH m.eH m.eH m.OH NH noom o.kH H.eH m.oH N.NH m.NH p.mH N.GH G.NH NH .uoom H.mH m.GH N.NH m.eH a.mH k.mH N.mH p.mH o boom m.0N a.mH m.ON G.GH m.ON H.0N H.0N o.oH mN .msz p.mH N.SH a.mH N.OH m.mH m.kH k.mH m.HH NN .msz e.mH m.HH R.NH o.m m.eH N.NH e.NH N.m mH .msz H.oH N.HH e.eH N.m e.mH m.mH N.eH G.m m .msw o.kH N.eH m.oH m.NH N.NH e.mH H.0H m.HH mN mHsn e.mH m.mH m.mH m.NH o.mH o.sH m.NH o.mH HN mHsn G.NH H.eH m.mH H.eH N.NH m.GH H.mH H.mH NH NHos N.mH e.oH a.mH m.oH o.mH a.mH H.mH m.NH n mHsn N.ON N.NH N.ON s.mH H.0N H.mH H.oN m.mH H NHsb OEDHO> >3 O\O .flGmHSOO OHSHmHOE EMT: mume \mHzHHHz ozHHHz HonHz oonHz HzHHoz ozHHoz Honoz NHonoz .mnoum couvzmz an oocHEHoumo mm .wmmH .HmnfioumomlmHSb mcHHSQ mpHm on“ mo Hommq HHom .mEo omno may mo pcmucou mHsumHoz coo: H NHQmem¢ 98 m.mH H.ON a.mH a.mH H.0N H.mH N.NH n.0N m .poo o.mH e.mH N.NH N.GH H.mH a.mH e.mH e.mH GN nomm m.oH p.mH N.SH m.mH N.NH m.eH m.eH o.mH NH boom m.kH e.NH H.NH p.mH N.NH s.mH m.mH m.mH NH .uoom a.mH m.mH H.NH m.NH m.mH G.NH H.NH o.ON G boom a.mH s.ON m.mH m.mH N.ON e.mH N.NH N.ON NN .msz N.mH m.NH N.mH m.eH p.mH o.oH N.mH H.NH NN .moz N.GH m.oH m.eH e.eH N.SH m.mH m.NH a.mH mH .mse m.oH o.oH k.mH k.eH m.oH o.eH m.mH m.NH N .msw N.NH m.kH o.oH G.GH N.NH m.eH m.eH o.mH NN NHsn G.NH m.kH H.NH N.GH m.mH a.mH m.mH a.mH eN mHsb H.mH m.mH m.NH H.GH >.mH N.GH H.6H m.ON NH NHsn a.mH m.mH n.5H H.NH m.mH N.NH N.SH m.HN s NHss p.mH e.ON a.mH e.mH p.mH N.NH m.wH N.HN H NHsn mESHo> an usooumm .pcmucoo musumHozHcmmz mumo HzHHHz ozHHHz HonHz oonHz HzHHoz ozHHoz Honoz oonoz .mnoum couusmz an omcHEHmumo mm .nomH HmnmfiummmlmHSh mcHHzo oHHm on» Ho H0>MH HHom .mEo oolom may mo ucmucoo musumHoz coo: HH XHDmem¢ emNHHHonm Hm \« omNHHHuumm uoz om \M mpmvmom EchoEEm.m o.H nuH3 Umpomuuxm \fl mmH ooH NNH mNH GmH ka HNH NmH omommHuuH HmH HmN me mmH wHN HMN mmH mNH omumm . IHHHHGD wmmum>4 NNH HGH mm OHH HGH HGH mNH OHH omummHuuH an mON mm oHH mNN mmN mm onH ompmm IHHHHGD > omN MNN mnH wMN mmH wHN mHH mHH UmummHHHH HmN mnN mnH mmH HmN Hem omH hmH ompmm :HuuHoD >H 05H HmH OHH mm mmH mmH mHH mHH omummHnHH HmH HwN oHH mNH HmH mON Nb om ompmm IHMHHcD HHH mkH meH mNH mm OHH NmH mo oHH omummHuuH om bmH th mMH wHN ONH mNH Nb pwumm IHHHHcD HH mmH OHH OHH mHH an mNH 05H OHH ompmmHHHH mmN mmN HwH mmH mMN mom ONN OHH omumm IHHHHGD H HEHm OSHm HEOm 020m HEHm \flOSHm HEOm \dozom msuoum .OZ GOHH GOHpomuoum UcH3 oz coHuomponm UGHB GOHummHHHH IMUHHmmm Amumuoon mom EmnmoHHxv M mHQmmmcmnoxm .aumoo HHom .mEo mH ecu um \Hz mHQmoocmnoxm co GOHummHHHH mo uommmm HHH XHQmem4 99 II”: NmH HMN mmH omH wHN HMN mmH mmH owEOsz me mMH MNH HMH mmH mNH HNH NHH pocOHDE p02 ommnm>< hmH mON hmH HmH MNN NMN HwH HmH ©m£0HSE mm mHH mm oHH mm OSH mNH OHH oocoHDE #02 > HmN wHN omN MNN HmN Hem mmH ONN pmcoHsz NHH MMH NHH HwN mbH hmH oHH mHH UmEOHSE uoz >H HmH HwN OHH HmH HoH mON mmH. mHH owQOHsz OHH mNH OHH mm Nb ow mMH mHH pocoHsE poz HHH om hmH mnH meH ONN onH OHH NmH pocoHsz mmH MMH mNH mm mNH Nb mm OHH omcoHSE uoz HH mmN MMN mmH OHH MMN mON hmH mNH omcoHsz HmH mmH OHH mHH ONN OHH onH OHH pocoHsE #02 H Hm Oh Hm om Hm Om Hm Om coHpmmHHHH oz GOHummHHHH coHummHHHH oz coHummHHHH mapmum .oz aoHp GOHuooHOHm ch3 oz COHpowHoum UGHB mcHQOHSE IMOHHmmm Homopomc mom EmumoHHxv M mHnmmmcmnoxm .zummo HHom .mao mH mzo pm z mHommmomzoxm so maHHOHsz no oommmm >H XHQZMmm< 100 APPENDIX VI Soil Exchangeable K, Above and Below the Perforated Plastic Fertilizer Sacks, One Growing Season After Placement. Exchangeable K (p.p.m.) epthcms.) O-7.5 7.5- 15.0- 22.5- 30.0- Treatment 15.0 22.5 30.0 37.5 (1) F1M0Io 275 70 70* 7o FOMOIO 173 70 78 78 (2) * FlMlIl 220 125 110 117 141 FOMlIl 165 102 102 102 78 (3) * FlMOIO 133 78 70 196 347 FoMoIo 102 110 102 102 78 (4) * FlMlIO 259 78 7o 70 FOMlIO 307 102 78 63 (5) * FlMOIO 117 86 110 86 110 FoMoIo 220 63 63 7o 73 * Depth of placement of fertilizer sack. 102 APPENDIX VI I NO —N Content of Soil Above and Below the Perforated Plastic Fertilizer Sacks, One Gorwing Season After Placement. NO3 - N (p.p.m.) Depth 0-7.5 7.5- 15.0- 22.5- 30.0- Treatment 15.0 22.5 30.0 37.5 (1) * FlMOIO 4.8 0.8 0.8 3.2 FOMOIO 2.4 6.4 1.6 3.2 (2) * FlMlIl 1.6 0.0 0.0 8.8 16.0 F0M1I1 0.0 1.2 0.0 1.2 0.0 (3) F1M0I0 0.0 0.0 3.2 37.6* 95.2 F0M0Io 0 o 4.0 19 2 24 0 0.0 (4) F1M110 0.8 3.2 4.0* 13.2 F0M1I0 4.0 18.0 19.2 15.2 (5) FlMOIO 10.8 6.4 3.2 21.6* 5.6 FoMoIo 1.6 3 2 4.8 14.4 0.8 * Depth of placement of fertilizer sack. 103 HON. NON. OON. HHN. OHN. wON. mON. OHN. woummHHHH eOH. OOH. HOH. wOH. HON. OOH. NOH. OOH. poammHHHHcD ommuo>¢ OON. OOH. wHN. OOH. ONN. OOH. OOH. OOH. omummHHHH wOH. OOH. OOH. OOH. OON. NOH. wOH. eOH. woummHHHHcD > OOH. NOH. OOH. NOH. wON. OON. OON. mmN. woummHHuH HOH. OOH. OOH. OOH. HOH. OON. OOH. OOH. owummHHHHcD >H OOH. OHN. OHN. OOH. OOH. mmN. OHN. OON. UmpmmHuHH HON. HON. wOH. OON. NOH. NOH. OOH. OHN. owummHHHHcD HHH OHN. NOH. wOH. OON. OOH. OON. OHN. OOH. UmummHHHH OHN. NOH. OOH. OwH. OHN. OOH. wOH. eOH. oopmmHHHHcD HH ONN. NON. wHN. OHN. ONN. OON. HON. ONN. UmuMOHHHH wOH. NOH. OOH. HOH. OOH. OHN. OON. OOH. poummHHHHcD H HEHm HEOm OSHm 020m HSHm HSOm OEHm 020m coHuompoum ocHB coHuowpozm UcHz oz msumum .oz coHu O coHpmHucmocoo HMHHOH m coHummHHHH tonHmwm .OOOH .ON umsmsd .mcHucMHmudo mcHBOHHom Gmeom OQHzonw oco .uchmz Home OIH .coHumecmocou HMHHOH m co QOHpmmHHHH Ho uomwwm HHH> anzmmm< 104 O0.0 O0.0 mm.o H0.0 O0.0 No.0 O0.0 w0.0 oopmmHHHH Ow.O O0.0 Ow.O O0.0 Ow.O O0.0 H0.0 O0.0 pmummHHHHcD ommao>¢ N0.0 O0.0 O0.0 O0.0 em.O Ow.O O0.0 N0.0 ooummHHHH Ne.O O0.0 O0.0 N0.0 w0.0 Ow.O ww.O N0.0 omumeHHHcD > O0.0 O0.0 O0.0 w0.0 ON.H OH.H wH.H ON.H pmummHHHH Nm.O OO.H N0.0 O0.0 Nm.O NO.H w0.0 O0.0 UmpmmHHHHcD >H wO.H NH.H O0.0 em.O O0.0 wO.H O0.0 O0.0 UmumeHHH w0.0 O0.0 Ow.O Hw.O O0.0 O0.0 Ow.O N0.0 omummHHHHcD HHH O0.0 O0.0 O0.0 ow.O OO.H OO.H N0.0 O0.0 oopmmHHHH O0.0 O0.0 ew.O Ne.O O0.0 N0.0 em.O Hw.O omHomHHHHcD HH ON.H O0.0 OO.H OO.H OO.H w0.0 O0.0 O0.0 UmummHHHH O0.0 NO.H N0.0 Ow.O Ow.O N0.0 N0.0 O0.0 UmummHHHHcD H HEHm HEOm OSHm 020m HEHm HSOm OEHm 020m ODMMHm .OZ GOHH coHuowuomm UGHB coHpowuoum UQHB oz COHpmmHHHH IMUHHmom coHpmHucwocoo HmHHoH z .OOOH .ON HOSOSN .mmchcmHmuso mcHonHom cOmmmm mcHzouw mco .uschz MUMHm O1H .coHumnpcoocoo HmHHom N no coHummHHHH Ho Hommwm XH mezmmm¢ 105 OO. ow. OO. OO. OO. He. OO. Ow.O OmummHHHH Ow. OO. NO. Ow. OO. we. Ow. Ow.O OmpmmHHHHcD omn~m>< ow. OO. Ow. HO. OO. Ow. Nw. OO. UwummHunH NO. Ow. OO. HO. HO. OO. NO. OO. woummHHHHcD > OO. Ow. OO. Ow. OO. OO. OO. OO. pmummHHHH Ow. OO. Ne. Ow. OO. wO. Ow. OO. OmvmmHHHHcD >H ON. HO. ON. ON. ON. Hw. OO. OO. OOHMOHHHH OO. HO. Ow. Ow. Ow. Ow. OO. OO. ooumOHHHHcD HHH OO. OO. Ow. OO. ON. OO. NO. wO. omHmOHHHH OO. wO. Ow. OO. Ow. Ow. Hw. OO. pwummHHHHcD HH wN. OO. ON. ON. Ow. Ow. Nw. Ow. UmemHHHH Ow. ON. OO. Ow. NO. OO. Ow. Ow. ooummHHHHcD H HEHm HSOm OSHm OZO HEHm HSOm OZHh 020m mDHmpm .OZ GOHH coHpmeHHH IMOHHmmm coHuomuoum UGHB onpowHOHm ocHB oz HOV COHHmnpcmocoo HMHHOH m2 .OOOH .ON umsmd< .mchcmHmuso mcH3oHHom c0mmmm OGHBOHU mco .pschz HOMHm olH .coHHMHHQOOGOU HmHHom m2 co coHpmmHHHH Ho uomwwm X XHQZMQAfi 106 OO.H OO.H OO.H eO.H OO.H OO.H OO.H OO.H omumOHunH OO.H OO.H NO.H OO.H HO.H OO.H OO.H HO.H omumOHnuHcO mmmum>¢ eO.H OO.H wO.H OH.N OO.H oo.N NO.H OO.H omummHunH OO.H NH.N ON.N OO.H HO.H NO.H mo.N OO.H OmummHHuHoO > NO.H OO.H OO.H OO.H OO.H eO.H OO.H OO.H oomeHuuH OO.H OO.H wO.H NO.H OO.H HO.H NO.H OO.H oopmmHHuHco >H eN.H oo.N OO.H wO.H Oe.H NO.H NN.H OO.H OmummHuuH OO.H OO.H HO.H eH.N OO.H Oe.H OO.H OO.H oomeHHHHcO HHH OO.H OO.H NO.H OO.H OO.H NO.H eO.H OO.H OmmeHuuH OO.H Oo.N HO.H No.N OO.H OO.H HO.H OO.H OoumOHHHHoO HH OO.H OO.H OO.H OO.H ON.H Oe.H OO.H ON.H OopmmHHHH Hm.N me.H OO.H OO.H HO.H OO.H HO.H OO.H OmumOHHuHco H Hsz Hzom osz ozom Hsz Hzom osz ozom magnum .oz coHu COHHOOHHHH IMOHHmmm 20Huomuonm wcHz oz coHuomponm UGHB HOV GOHpmnpcmocoo HMHHOH mo .OOOH .ON pmoms¢ .OcHucmHmuso mcH30HHom cOmmmm mcH3ouw mco .uschz HomHm OIH .coHumecoocoo HMHHom mo so COHummHuHH Ho Hommmm Hx XHQZWmm¢ 107 ON.N Ow.N Ow.N Ow.N OO.N NO.N ON.N OO.N .UmNHHHpHmm OH.N OO.N Ow.N OO.N Ow.N ON.N Nw.N OO.N omNHHHuancD wmmnm>< OO.N OO.N wO.N NO.N wO.N OO.N wO.H NH.N omNHHHuHmm OH.N Nw.N wN.N OO.N wO.N NH.N OH.N ON.N UmNHHHpHchD > OO.H OO.N OO.N NO.N ww.N OO.N wO.N OO.N UmNHHHuHom NN.N OO.H OO.N ON.N OO.N NO.N OO.N ww.N ,omNHHHpHomcD >H OO.N ww.N OO.N Ow.N ON.N Nw.N wN.N NO.N UmNHHHuHmm NN.N OO.H Ow.N OO.N OO.N wO.H wN.N OO.N UmNHHHHHomcD HHH OO.H OO.N wO.N Ow.N OO.N OO.N NO.N NO.N omNHHHpHmm NH.N OO.H ON.N OO.N ON.N NN.N OO.N NO.N omNHHHuHchD HH OO.N wO.N wO.N NO.N NO.N OO.N NN.N OO.N UmNHHHuHmm wN.N ON.N OO.N NN.N OH.N OO.N Ow.N OO.N omNHHHpHchD H Hz 02 Hz 02 Hz 02 Hz 0: UmummHHHH UmpmmHHHHCD UmummHHHH UmummHHHHCD msumum .oz coHu HmNHHHuHmz IMOHHmmm coHpoouonm 62H: coHuoououm ocH3 oz . . HOV cOHumupcmocoo HMHHOH z .OOOH .ON,umsms4 .mcHHCMHmuso mcHsoHHom commmm mcHzonw 0:0 .uschz HUOHm OIH .GOHumuu Icmocou HMHHom z co mxomm OHHOMHm oopmuoHme CH coHHMOHHQQN HmNHHHuHmm Ho Hommmm HHN Nanmmm¢ 108 OON OOm Omm .ON O.H O.m OO. ON mm I Om I e I m. I N.H I NH. ON mm om m. N.H NH. O N OH OH I ON e I m I N. I OO. I OO. O N OH OH ON. OO. OO. O N I e I O ON I N m I H I OO. I OH. I OO. O H .s.m.m ON m as so Oz z m coHnmnpcmocoo ucmEOHm pquHHsc HMHmcHz Aucmmmnm zHonu mEOH Imfimm mocmHonmwv mmcmn Hmfinoz AmHQMOOHuoc on poc Owe Ho OMS mEOp Imazm mocoHoHHmov oDMHomfinmucH AmHQMOOHHoc mEOp Imamm mocmHonmov OocoHonoo mmcmm HHHN XHQmem4 .AOOOH .zsz Hmummv pschz chHOHHHmu :H mspmgm HmcoHuHHpsz mo mmmcmm msoHHm> mcHHHEHHoo mpcoEOHm pcmHHpsz HmumcHz Ho mGOHumupcmocoo HmHHom 109 OO.H ON.H O0.0 O0.0 OH.H ON.H H0.0 N0.0 coHuoououm UGHB wH.H NH.H H0.0 O0.0 OO.H HN.H w0.0 O0.0 GOHuomponm UGHB oz mmmuo>¢ O0.0 w0.0 O0.0 ww.o O0.0 OH.H N0.0 O0.0 coHuoououm OGHB OO.H O0.0 O0.0 O0.0 O0.0 OO.H w0.0 ee.o COHuomuomm UGHB oz > NH.H ow.H O0.0 O0.0 OO.H NO.H OO.H O0.0 coHuomuonm ocHz NH.H NH.H w0.0 OH.H NH.H ow.H NO.H O0.0 COHuomuoum ocHa oz >H OO.H ow.H w0.0 w0.0 OO.H OO.H O0.0 O0.0 coHuomuoum OCH: N0.0 OH.H w0.0 O0.0 O0.0 NO.H O0.0 O0.0 coHuompoum UcHS oz HHH OH.H NH.H O0.0 O0.0 ww.H NH.H O0.0 O0.0 GOHuomHOHm ocHz NO.H OO.H OO.H w0.0 NN.H OO.H OO.H O0.0 coHHUOHOHm UGHB oz HH NO.H ON.H OH.H O0.0 ON.H ON.H w0.0 O0.0 coHuomHoum UcHz NO.H ON.H O0.0 O0.0 NH.H ON.H w0.0 O0.0 coHuomuoum ocHz oz H Hsz Hzom osz ozom Hsz Hzom osz ozom ompmmHHHH ooymmHHHHcD coHpmoHHmmm usmonom .GOHumHucwocoo z HMHHOH cmwz mcHzouo ocooom .uschz MUMHm .mcHucMHmuso mcHBOHHom acmmmm OIH nOOOH .OH NHOO no coHumugcoocoo z umHHom c662 >HX mezmmm¢ 110 OO.N OO.N OO.N OO.N wH.O NO.N OO.N wO.N quuomuoum UGHB OH.O HO.N wH.O O0.0 wN.O H0.0 N0.0 OO.N coHuoopoum chB oz ommuo>< OO.N OO.H NO.N OO.N ON.O NO.N OO.N OO.N coHuomuoum UQHB OO.N ON.N ON.O wO.N wH.O OO.N wO.N OH.O cOHuomponm UGHB oz > NO.N OO.N wO.N OO.N ON.O OO.N OH.O Ow.N coHHomHonm UcHz N0.0 N0.0 w0.0 Ow.O w0.0 O0.0 wN.O N0.0 coHuoououm ocHB oz >H N0.0 ww.N O0.0 OO.N OO.N wO.N wO.N ow.N coHuomHonm UcHz OH.O OO.N OH.O NO.N ON.O NO.N N0.0 wO.N coHpoouoym UGHB oz HHH OO.N OO.N wO.N wO.N wO.N OO.N ON.O ww.N QOHpomuoum UGHB ON.O Ne.O OO.N O0.0 O0.0 ww.O O0.0 OO.N coHpowuoum ocHB oz HH N0.0 OH.O Ow.O O0.0 O0.0 wo.O NN.O N0.0 coHpompozm OQHB wN.O OO.N O0.0 NH.O ow.O OO.N Ow.O O0.0 coHuoogomm UQHB oz H HEHm Hzom OZHh OEOh HSHm HSOm OSHm 020m woummHHHH omumeHHHcD coHHMOHHmom unmouom .cOHHmHucwocoo z HMHHOH cum: mcHBOHG Ucoowm .pschz xUMHm OIH >X XHflzmmm< mcHHGMHmHDO mcHBOHHom c0mmom “OOOH .OH OHSO so COHpmHucmocou z HOHHom cmmz lll IHI O.wHO OOO.N O.HOw OOO.N 0.000 Ow0.0 0.000 HOH.O coHu Iomponm ocHz on H0 Hmuoe 0.00N OOw.H w.OON OOO.H 0.0HN OON.H 0.00N NOw.H H4308 0.00 OOH.O N.Ow HON.O H.wO OON.O 0.00 OON.O O N.OO OOw.O w.OO OON.O w.OO OOH.O 0.00 HNw.O w 0.0w OO0.0 O.HO OO0.0 0.0w NON.O N.Ow wON.O O H.OO HO0.0 w.OO OON.O O.HO NN0.0 0.00 HOH.O N 0.00 ONN.O 0.00 OO0.0 O.Hw wON.O 0.0w HON.O H woummHHHHcD 0.0eN OOw.H 0.00N HNN.H O.HON OOO.H 0.00N OOO.H H4809 O.wO OOw.O O.HO HOH.O N.OO OHN.O I I O 0.00 NHN.O 0.00 OOw.O 0.0HH OO0.0 0.0wH OO0.0 w N.Hw OON.O 0.0N OwH.O 0.00 OO0.0 0.0w OwN.O O 0.00 NON.O O.HO OOH.O N.Hw HON.O 0.00 HON.O N w.OO Nw0.0 H.Oe OON.O 0.0w OON.O O.wO OH0.0 H HmEo.vmv Hmamv HmEo.wmv AmEmV HmEo.wmv Awamv HmEo.vmv HmEmO .Hm mmmH .u3.Q.O .Hm wmmH .H3.Q.O .Hm mmmH .p3.Q.O .Hm mme UB.Q.O o 0 .oz Hsz Hzom osz z m . mom owpmmHHHH QOHuoououm UQHB oz .OOOH .OH Hmnfimummm co Howcmo sonmmmmm mmuB mnu um UmcHEHouoo .mzHucmHmpso HOHHN cemmwm OGHBOHU oco upschz MOOHm olH Ho wouH Hmoq 0cm uszoz OHQIco>O Ho QOHHMHmm H>x XHQZHAmd 112 O.HOO OH0.0 H.OOO OOO.w 0.0HO OO0.0 0.0wO OO0.0 coHuomu Ioum chB O0 HmHoB N.HNO OwO.H w.OOO wON.N 0.00N HOO.H 0.00N wOw.H HNBOB w.OO OO0.0 0.0NH ww0.0 H.OO ONw.O w.OO OON.O O 0.00 OO0.0 H.Ow wON.O O.wO OH0.0 O.Hw NwN.O e 0.00 wHN.O 0.00 ON0.0 0.00 Ow0.0 0.00 NON.O O 0.00 OOw.O 0.00 ONw.O H.Hw OwN.O O.wO NHN.O N 0.00 NON.O O.NO OO0.0 0.00 OHN.O 0.0NH NO0.0 H UwummHHHHcD 0.0wO OOO.H 0.0ww HOO.N 0.00N OOw.H H.OON NOO.H HX xHQmem¢ 113 OwHN OOHN wOON OowN OOOO OOON OOwN OOON omonzz wOOH OOOH OwON OOON ONOH OOOH OOON ONwN OmnoHsz poz mmmyo>¢ OOwN wowN OOHH OOHN Nwa ONOw OOOH OOON OwnoHoz OOOH NOwH ONOH OHOH HOwH NHHN OOON OowN UmQOHsz poz > wOON OOON OOOO OOON ONOH NOON OOHO OOON omcoHsz OOON onH OHNw OONw OHOH OwOH OOOO HNON U030Hsz poz >H NwHN OOON NOOH OOON OOON OOOH NOwN NNON UOQOHSS NONH HOOH OOOH OOHN wwwH OOOH OOHN NOON omconz uoz HHH ONOH OwNN wOON wOHN wOON OOOO HOHN ewON UmcoHsz OOHN OONN OOON OHON OOOH wOON OOwN OOON omcoHsz poz HH OOOH OONH NwOH OOON wOOO OOOH wNON OOHO omnoHsz OOOH HOOH OOwH ONOH OwNO HOwH HOON NOOH wocoHsz #02 H OONHHHH pomHH ooNHHHu UmNHH OONHHHH UoNHH UONHHHH OONHH IHchD IHuHom IHchD IHuHmm IHchD IHuHmm IHoHcD IHpuwm ompmmHHHHcD UmpmmHHHH_ popmmHHHHcD UoummHHHH cOHpomuonm OCH: oz coHpoogoum OCH: msHMHO .oz GOHH hwao _.vm mwum HOOH mcHnonz IMUHHmom .OOOH .OH uwnsoummm Omnsmmmz .OcHucmHmuso HouOO c0mmom mnHzono oco .omHHQQN musmfigmmne wgu Hows: .uchmz MomHm oIH Ho OOHH HOOH HH>X XHQZMQm< 114 OOOw OOOw wOmw wOOO OHOw OOOw Oowm OOOO GOHHUOHOHQ UGHB OOON NHNN HOON OHNN wOON ONON OwHN OwON COHHOOHOHQ UQHB OZ mmmum>¢ ONON OHow wHOO OONO OOOO OOwO OOOO OOOO coHuoououm ocHz OOOO NOOH ONNO wNOO OOOO OONN OONO wNON coHpomuoum UQHB oz > OmOO OwOO OOwO ONOw OOOO OONO wOOO NOON coHHOOHOHm OCH: HOOH OOON NOOO HOO OOOO OHON OOOH OOHO coHHompoum UGHB oz >H OOOO OOOO OOOw OOHw OONO OOOO HOHw ONON coHuowuozm OCH: OOwO OOON OOOH ONON OOOH OwON OONN OOON coHuomHonm ocHz oz HHH OwHO OOOO OHOO OOOO OHOO OOOw OOOO OOOO coHuomHOHm ocHz HNHO OOON OOON ewON OwON OOO OOOH OOON coHpompoum chB oz HH. OOwO NOww OOOH ONOO OOON OOOO ONHN wOOO coHpomuoum ocHz OOON ONOH HONH OOOH OOOH OONN OOOH OOOH coHHUOHOHm wcHB oz H H H H O O H O O H H H O O H O O :OHu 2 m E m 2 m E m S m 2 m 2 m 2 m IMOHHQmm OmpmmHHHH ooummHHHHsz NEO .mmnm wwwH OcHHGMHmpoo HOHHN cemmmm Ucoomm .pschz MomHm oIH “OOOH .OH OHSO co Hon comm CH owHB Hmmm Ho OwHN wwwH HHH>x xHflzmmm4 115 eO ON ON ON OO OO NN HN coHuomuozm OOH: ON NN ON OH ON HN eH OH coHuomuoum OOHz oz OOOHO>O OH ON OH HN Oe Oe ON ON OOHuomHozm OOH: HN OH OH OH OO eN OH OH QOHuoouozm OqHz oz > He OO OO OO Ne ON ON NN aoHpoououm OcHz eN OO HO HO ON ON OH ON :oHHoououm OcHz oz >H eO NO OO HO OO OO OH HH coHpomuoum OcHz ON OH OH OH HN OH NH eH aoHpomHozm OqHz oz HHH HO HN ON OH OO OO eN OH coHuooaoum Osz ON NN ON HN eN OH NH eH coHuoouon OcHa oz HH ee OO ON OO OO eO ON ON aoHHompoHO OOH: ON ON HH OH NH OH OH OH OOHuoouozm OcHz oz H HzHO Hzom osz ozoz Hsz Hzo.O ozHO ozo coHp ooummHHHH omemHHHHcD IOOHHmdm .mEo .Hoonm HmcHEpr O.HOO» pcmuuso mag Ho panoc cmmz OGHHGOHQHSO mcHBOHHom cemmmm Ucooom .uschz MomHm olH «OOOH .NN OHDb co poozm HOCHEHOB HOOOHO O.Hmmz ucmHHSU may Ho uzmHom cmmz XX XHQmem¢ 117 IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIII