INVITED PAPERS AND ABSTRACTS OF CONTRIBUTED PAPERS

Joint Meeting of the Northeastern Branch of

the American Society of Agronomy and

Eastern Forage Improvement Conference

July 13-16, 1997 University of Maryland College Park, MD 20742

CONTENTS

Section 2A-1-Forage Graduate Competition Tuesday, 15 July ......................................................................... 3

Section 2A-2-Forage Genetics & Pathology Tuesday, 15 July ......................................................................... 3

Section 2B-1-Environmental Quality Tuesday, 15 July ......................................................................... 4

Section 2B-2--soils, Environmental Quality & Plant Sciences Graduate Compeition Tuesday, 16 July ......................................................................... 5

Section 3A-I-Forage Management Wednesday, 16 July ....................................................................... 6

Section 3A-2-Forage Fertility Program Wednesday, 16 July ....................................................................... 7

Section 3B-I-Natural Resources Management Wednesday, 16 July ....................................................................... 8

Section 3B-2--Cropping Systems & Sustainable Agriculture Wednesday, 16 July ....................................................................... 8

Prepared in cooperation with

ASA Headquarters 677 South Segoe Road

Madison, WI 53711

AUTHOR INDEX

Ali, A.A., 4 Harkcom, W.S., 7 Paltineanu, I.C., 8 Allard, G., 3 Harper, J.K., 6 Pesek, J.D., 9 Allinson, D.W., 3 Hatch, L. W., 7 Pionke, H.B., 8 Andrews, S.P., 5 Hatley, E.O., 3 Preer, J.R., 4 Anyama, L.O., 9 Hill, R.L., 9

Holderbaum, J.F., 9 Rabenhorst, M.C., 8 Bagley, B.B., 4 Hossain, M.A., 4 Rayburn, E.B., 6, 9 Balasko, J .A., 7 Hower, A.A., 6 Reeves, J .B., 3 Bao, G., 3 Hull, RJ., 3 Reid, W.S., 7 Barthakur, N.N., 6 Hypes, S.L., 7 Robinson, J .M., 5 Bauchan, G.R., 4 Roth, G.W., 6 Beegle, D.B., 7 Islam, K.R., 4 Britz, SJ., 8 Sanderson, M.A., 6 Bryan, W.B., 6, 9 James, B.R., 4 Sarjaz, M.R., 6 Bunker, S.D., 4 Jiang, Z., 3 Shirey, J .A., 5 Burt, R.F., 8 Johnson, D., 6 Siegrist, H., 6

Jones, PJ.H., 6 Sims, J. T., 5, 8, 9 Campbell, T.A., 3 Skiles, E.H., 7 Castonguay, Y., 3

Kessler, R.J., 6 Sone, M.N., 4

Chekol, T., 3, 7 Starr, J.L., 8 Cherney, D.J.R., 7 Krill, T., 6

Cherney, J.H., 7 Krueger, C.R., 8 Taylor, R. W., 9 Chernikova, T., 5 Kyper, R.A., 6 Thomison, P.R., 6 Classens, A., 3

Leblanc, E., 5 Tunney, H., 8

Coale, FJ., 5 Collins, A., 3 Lee, E.H., 5 Uniatowski, B., 9

Levine, E.R., 9

Daughtry, C.S. T., 5 Liu, L., 8 Vadas, P.A., 9 Decker, A.M., 9 Liu, Y., 5 van Berkum, P.B., 4 Devine, T.E., 3 Lotz, L., 6 Vasilas, B.L., 9 Dyson, D.M., 9 Lozier, J., 6 Veneman, P.L.M., 5

Lucey, R.F., 3 Vough, L.R., 3, 7 Elhelu, M.A., 4 Luka, N.J., 8

Elwinger, G., 6 Wiedenhoeft, M.H., 7 Eriksen, L., 5 Michaud, R., 3 Estes, G.O., 4, 5 Min, D.H., 3, 7 Xia, Z.L., 3 Everhart, J., 6 Mitchell, J.R., 4 Xing, B., 5

Mt. Pleasant, J., 8 Famuditimi, 1.0., 4 Mulchi, C.L., 4, 5 Zhao, J., 5 Fanning, D.S., 8 Murphy, T.B., 6

Geyer, A., 6 Nadeau, P., 3 Giberson, E.M., 7 Griffin, T.S., 7 O'Neill, N.R., 4

NORTHEASTERN BRANCH ABSTRACTS

TUESDAY, 15 JULY Sec. 2A-I-Forage Graduate Competition

Dairy Manure Applied to Alfalfa, Grasses and AlfAlfA­Grass Mixtures! Beeget on Forage Yield and ~. D.H. MIN*, L.R. VOUGH, J.B. REEVES, and T. CHEKOL, Univ. of Maryland.

Little is known about the utilization of dairy manure nutrients for forage production with alfalfa, cool­season grasses and alfalfa-grass mixtures, especially when applying several times per year. The objective of this study was to evaluate the herbage yields and quality for alfalfa (Nedlcago sativa L.), orchardgrass (Dactylls glomerata L.), tall fescue (Festuca arund.tnacea Schreb), reed canarygrass (Phalar.ts arund.tnacea L.) and orchardgrass and reed canarygrass in combination with alfalfa for utilizing nitrogen from various dairy slurry application rates and time schedules. This study demonstrates that split­applications of higher rates of dAiry slurry did not decrease the herbage yield, especially for the alfalfa and alfalfa-grass mixtures. Generally, frequency of application of the same total amounts of dairy slurry applied did not affect herbage yield. Crude protein increased more in grasses than alfalfa and alfalfa­grasses. Acid detergent fiber and neutral detergent fiber were not generally affected by the manure Application rates.

D.H. Min, (301) 405-1325

Detennining Nitrogen Mineralization Rates urxier Penomri.al GrasslaOOs as a Predictor for Nitrogen Fertilizer Recalm!ndatia1S. Sr. Augusta OOLLINS* and D.W. AILDmf. thiv. of Qxmecticut.

Nitrogen use efficiency in a grassUnl systan is I!Bcimized Wen availBhiliq am uptake coincide with need. Efficiency of N use would be enbanced if mineralizable N were known. '!be purpose of this research project is to umitor N mineralization rates in relation to yield in order to dewlap a IIOre refined III!thod of making N fertilizer ~tions in a perennial grassland S}'SteD. Varying rates ~f N were_applied to two cool-season grasses am cmcentratia1S of 1114 anc.! R)3 in the soil were masured thIOughout the season. as well as 10 CCIOCeIltrations in the plsnt tissue. Initial attmpts to determine criticn tinE periods for soil ~li.ng within three different harvest cycles. and critical CCIOCeIltratia1S in soil am plant tissue as a basis for making N fertilizer ~tia1S. are pranising. In vitro long teIm incubations, as well as in situ incubatia1S in the field-:-cootdinate well with mineralizatioo at different soil saq>ling dates. In the seccni year of the experiDmt, nitrogen treabll!Ots have been broadened, and an additi.ooal mthod of ueasuring nitrate fluxes in the field, has been introduced.

Sr. A. Collins, (203) 266-m7

Distribution of NilJate Reductase Activity in Kentucky Bluegrass in Relation to Nitrate Supply. Z JIANO· and RJ. HULL, Univ. of Rhode Island

To investigate N use efficiency mechanisms of a N-demanding turfgrass, Kentucky bluegrass (Poa pralensis L), an in vivo method was adapted to analyze the activity of nitrate reductase (NRA) in leaf blades, leaf bases+stems and roots of 'Livingston', which perfonned better under high N trials and 'Merit', which perfonned bener under low N, following exposure to 0.15. 0.25, 0.65, 1.20 or 5.20 mM NaN03 for 24 h. Mean leaf NRA of 'Livingston' and 'Merit' was 1.53 and 2.28 fUIlol NO,z-g-1 fresh leaf trl, respectively. Leaf NRA in 'Livingston' responded to nitrate supply better than 'Merit'. Mean stem NRA of 'Livingston' and 'Merit' were 0.05 and 0.15 ",mol NQz- g.1 h-I, respectively, and neither cultivar responded to nitrate supply. Root NRA was not detected in either cultivar following 1 h dark anaerobic incubation. However, 4.5 or 16 h incubations revealed root NRA to be 0.02-0.04 ",mol NQz'g-1 h-I. We conclude that NRA occurs mainly in leaf tissues of Kentucky bluegrass although the assay for stem and root NRA may underestimate actual values.

Z. Jiang, (401) 874-5994

3

Characterization of Alfalfa Populations Deriyed from Selection for Cold Tolerance. A. CLASSENS·, R. MICHAUD. P. NADEAU, Y. CASTONGUAY and G. ALLARD, Univ. Laval and Agriculture and Agri-Food Canada. Sainte-Foy, Quebec.

Cold tolerance is recognized as a major limiting factor for wintersurvival of alfalfa. Two cycles of selection were performed in alfalfa (cv. Apica) for cold tolerance. Briefly, 1500 plants were cold hardened and subjected to three successive freezing stresses. At the end, 100 plants were selected and intercrossed to produce a second cycle. The original population (Apica) and the two populations derived from selection (CTl and CT2) were evaluated for cold tolerance (L T so) and cryoprotective sugar accwnulation. There was a significant increase in cold tolerance as a result of the selection and the selected populations had superior regrowth after freezing. The populations differed significantly in their cryoprotective sugar content at the mid and late winter sampling dates.

R. Michaud, (418) 657-7980

TUESDAY, 15 JULY Sec. 2A-2-Forage Genetics & Pathology

Performance of Soybean Lines Bred for Use as Forage in Tests in the Northeast. T.E. DEVINE.* E.O. HATLEY, and R.F. LUCEY, Weed Science Laboratory, USDA-ARS, BeltSVille, Ht Pennsylvania State University, and Cornell University.

Earlier in this century, soybean were used in the US primaril as livestock forage. Only plant introductions from Asia whic had not been bred for use as forage nor for adaptation to the US environment were available for this purpose. At Beltsville modern multiple pest resistaot graio-type soybeans were crossed with a hay-type introduction. Visually based pedigre selection was imposed on successive generations planted in alternate years at either Beltsville or Pioe Grove Mills, PA. Derived lines were used in a second cycle of hybridization with grain-types, followed by additional selection at Beltsville as well as Pine Grove Mills aod Orange. VA. A line, thus bred. produced forage yields of 12,739 and 5.705 lbs DM/acre in 1995 and 1996 respectively at Chazy, NY with 14.4% crude protein. Forage yield at Canton, NY in 1996 was 8,124 Ibs DH/acre. At Rock Springs, PA the same line yielded 5.718 and 5,600 lbs DH/acre in 1995 and 1996 respectively. The 1996 yield was significantly reduced by leaf drop prior to late harvest.

T.E.Devine, (301) 504-6375

Collection and Evaluation of the Section Platycarpe from the Peoples Republic of China. T.A. CAKPB~ G. SAO and Z.L. XIA, Agricultural Research Service.

The Peoples Republic of China (PRC) is the center of origin of several species of the section Platycarpae, which could contain genes that would be of benefit to alfalfa (HedIcsgo sstiva L.) Of particular interest are HedIcsgo srchiducis-nicolal Sirjaev, H. edgeworthll Sirjaev, and H. ruthenlcs (L.) Ledebour. Ninety H. ruthenlca accessions collected from 15 diverse environments in Inner Mongolia were evaluated in the field at Beltsville KD (USA) during 1993-1996 on a pH 6.4 soil deficient in boron. Significant variation was noted in nine agronomic characters, including tolerance of boron deficiency and leafhopper (Emposscs fsbse Harris) stress. Significant variation was noted in root-environment Rhizobia, and at least one new species has been identified so far. A 1996 Yunnan Province exploration yielded 30 H. edgeworchll accessions; evaluation is underway. Analyzes indicate that H. ruthenlcs may have agronomic potential and provide genes that could be of benefit to alfalfa.

T. A. Campbell, (301) 504-5638

4

Diploid Alfalfa Chromosomes and their C-Banding Polymorphisms. G.R BAUCHAN* and M.A HOSSAIN. USDA-ARS, Beltsville, MD.

Chromosomes of two diploid (2n =2x = 16) subspecies of Medicago sativa, ssp. caeruJea and ssp. falcala were studied. A modified C-banding technique and an image analysis system were used. Nine of the thirteen accessions of ssp. falcala have only centromeric bands, however, the other accessions have 1-5 pairs of chromosomes with a terminal band on the short arm. Variation in the number of chromosomes with terminal bands exists between individuals within an accession. Some interstitial bands were observed on the short arm of the chromosomes. B­chromosomes where found in two individuals in two different accessions. A multitude of bands are observed in the C-banding pattern of ssp. caeruJea enabling the precise identification of each chromosome. In some of the accessions a reduction in the number of bands were observed possibly due to hybridization with ssp./alcola. The differences in banding patterns between the diploid subspecies makes it possible to identify hybrids between these subspecies.

G.R. Bauchan (301) 504-6649

AFLP Characterization of Col/etotrichum Isolates Pathogenic to Alfalfa N.R. O'NEIT.L and P.B. van BERKUM, USDA-ARS, Beltsville, MD.

A major reason for the limited success in disease management is our limited understanding of the genetic structure of pathogen populations. A new molecular genetics tool, Amplified Fragment Length Polymorphism (AFLP) DNA fingerprinting, was applied to anthracnose disease pathogens of alfalfa !O assess the levels of genomic variations among species, races, and isolates In the genus Colletotrichum. Complex fingerprint patterns enabled the placement of unusually virulent anthracnose pathogens into two species. Dendrograms were generated from data analyzed by parsimony and by the distance method using either simple matching or Jaccard coefficients. Similarity matrices generated from three primer pairs were highly correlated The AFLP technique was useful for the genetic characterization of individua isolates within the complex genus Colletotrichum because of the ability to generate large numbers of polymorphisms and the consistency of the PCR amplification. An understanding of fungal population genetics and of the extent of pathogenic variation and mechanisms that direct this variation is essential if disease management through stable genetic resistance in alfalfa is to be achieved.

N.R. O'NeiU, (301)504-5331

TUESDAY, 15 JULY Sec. 2B-I-Environmental Quality

Beneficial Use of Organic Wastes on Turfgrass and Ornamentals.

J. R. PREER·, M. N. SONE, I. O. FAMUOmMI, and M. A. ELHELU, Univ. of the District of Columbia. Turfgrass plots were established on a Christiana silt loam using treatments of 146 Mg/ha biosolids compost (BSC), 146 Mg/ha yard trimmings compost (YTC), and 2 Mg/ha 10-to-10 commercial fertilizer, and planted with tall fescue (Festuca arundirlaceae Schreb.) and Kentucky bluegrass (Poa pratensis L.) in a split-plot design. Ornamental plots were established with the same treatments, and planted with zinnia (Zinnia elegans L.). In the first year, growth rate of both tall fescue and Kentucky bluegrass were significantly greater with BSC than YTC and fertilizer, which were in tum significantly greater than control. Total number of zinnia blooms and number of blooms per plant increased with treatments over control, BSC > fertilizer> YTC > control.

J. R. Preer, (202) 274-5937

NORTHEASTERN BRANCH ABSTRACTS

Soil Morphology, Drainage Class and Nitrate Concentration Relationship in Shallow Ground Water of Riparian Forests in Maryland. B.B. BAGLEY* and B.R. JAMES, University of Maryland.

Huch of the research on riparian forests areas within the ~lid-Atlantic Region has concentrated on the nitrate reduction by plant uptake and different nitrogen reduction processes. The purpose of this study was to examine soil types and their effect on nitrogen reductions and drainage into surface waters. Soil drainage classes may affect nitrate concentration in riparian shoreline ecosystems of the Chesapeake Bay. Six different soil types comprising part of a topohydrosequence were studied within the research site. Each soil type was examined for its effect on nitrate attenuation and the flow through drainage conditions. Results of this study show the effectiveness of detailed soil mapping and soil morphological interpretation on the degree of nitrate reduction which may result as groundwater flows from agricultural land through riparian areas.

B.B. Bagley, (302) 739-4761

The Composing Option for Organic Wastes' Process PrQperties and Performance. G. O. ESTES·, J. R. MITCHELL and S. D. BUNKER, Univ. of New Hampshire.

Composting of the organic fraction of the solid waste stream is rapidly expanding to achieve volume reduction and imprOVed physical/chemical properties for market acceptance. Landfill closures and bans on leaf7yard waste disposal are forces driving initiatives toward composting. Limited land areas in many states will necessitate the production of uniform, quality composts amenable to interstate commerce. Compost processes, feedstocks and final product are variable. Assessing plant performance in soils amended with composts having different properties is difficult. Results from field and greenhouse studies with different composts are presented to illustrate benefits and key measurements important to pre-plant evaluation of compost quality.

G. O. Estes, (603) 862-3220

Effect of COl and Q on Quantity and Ouality Qf son Organic Carbon. K.R. Islam", A.A. All, and C.L. Mulchi, University of Maryland \md Zigzag University, Egypl. Soil is a dynamic repository of C in terrestrial ecosystem. This srudy was conducred to evaluate whether increases in concentration of tropospheric gases (C02 or q) have affected the quantity and quality of soil C. Soybeans were grown in open-top cbambcrs and exposed ambient and + ISO mL L·1 for 12 h day ·1 (5:00-17:00 h ES1), 7 days wk·1 and ambient and +40 ~L L·1 for 7 h day·1 (9:00-16:00 h EST), 5 days wlc'l for 12 weeks under irrigated and non-irrigated conditions. Results indicared that microbial biomass C in soil collecred from open­top chambers is significantly increased under high CO2 and irrigated conditions, however it decreases under high levels of OJ. Particulate organic C in soil increased under high C~ treatment but decreased under high)O exposure. Among the chemical fractions of soil C, the O.5M NaHCO) extracted C pool is significantly affected by CO2, 0) and irrigation treatments. On the other hand, the O.SM NaOH extracred humic acid, fulvic acid and glucose C did not significantly. Combinations of treatment of easily and moderately oxidizable C fractions are significantly increased by CO2 and irrigation treatments but decreases under ~ exposure. Resistant fraction of soil C did not varied significantly.

C.L. Mulchi, (301)-405-1328

NORTHEASTERN BRANCH ABSTRACTS

TUESDAY, 15 JULY Sec. 2B-2-Soils, Environ. Quality & Plant

Sciences Graduate Competition

Bioavailability of Nutrients and Metals Followjng Soil-Incorporated Organic Wastes. 1. ZHAO- and G. O. ESTES, Uruv. of New Hampshire.

Greenhouse studies were conducted from 1994-95 at UNH to evaluate the effects of soil temperature on N release from three organic wastes and its uptake by com. In 1995-96, the effects of soil acidity on bioavailability of heavy metals to three vegetable crops were determined. Results showed that the concentration of nitrate-N in soil amended with biosolids was about twice as high as that with manure, and six times as high as that with compost. At the low and intermediate application rate ofbiosolids, N uptake by com increased with increasing soil temperature, while at the high rate no relationship existed between soil temperature and N uptake, possibly due to phytoxicity of elevated levels of ammonium-No All vegetable species -lettuce, bean and radish - showed poor growth at low soil pH «5.3). Concentrations of Zn and Cu in the edible portion of plant tissue of all species were elevated with decreased soil pH.

1. Zhao, (603) 862-3209

Measuri0i Soil Redox' Does the JJse ora Salt Bridee Prodyce More Reliable Yal.u§? S. P. ANDREWS·, Y. LlU, B. XING, and P. L. M. VENEMAN, Univ. of Massachusetts at Amherst.

The application of soil redox potentials obtained by means of platinum cathode in conjunction with a calomel or AgCI reference electrode in field measurements has been controversial. We discuss the relationship between Pt cathode, reference electrode, and salt bridge depth on the variability of redox values and stabilization times using two soils maintained under three different moisture regimes. Results indicate that the precision of in situ soil redox measurement has been overstated. Both bridge and non-bridge systems produce varying redox potentials suggestive of dynamic non­equilibrium soil conditions. The use of broad redox value ranges to describe the mixed potential status of in situ soils is acceptable when assessing the redox of that soil system. Individual redox values, however, may show a considerable range due to experimental error rather than being indicative of specific redox conditions.

S. P. Andrews, 413-545-3068; sandrews@sophia.smith.edu

Municipal Solid Waste Compost aDd Nitrogen Management. L_ Eriksen* and F_J_ Coale, Univ. of Maryland.

MuniCipal solid waste compost can be used to provide crop nutrients. The high carbon to nitrogen ratio in the compost can cause soil N ~bilization. Supplemental N application must be managed to both satisfy crop N demands and to avoid supplying excess soil N that may be leached from the root zone to groundwater. The objective of this study was to determine optimum application' rates of compost and N fertilizer to max~ize corn (Zea mays) productivity while min~izing N leaching in a two year crop system cODsisting of corn followed by a rye (Secale cereale) cover crop followed by corn_ Four rates of compost and five rates of fertilizer N were evaluated. In the first year corn silage and corn graiD yields did not differ across compost levels. In the second year rye, corn silage, aDd corn grain yields increased with increaSing compost levels. Soil nitrate nitrogen levels decreased inversely proportional to compost levels until December the first year when soil nitrate nitrogen levels began and continued to increase proportional to compost levels.

L. Eriksen (301) 405-1349

5

Effects ofNatw"a1 Weathering on Fonn Nld Solubility of Arsenic from Coal Fly Ash and Fly Ash-Amended Soils, J.A. SffiREY" and J.T. SIMS, Umv. of Delaware.

The disposal of coal fly ash, a by-product of burning coal for electric power generation, is a growing problem which has led to interest in alternative end uses. One alternative is to use fly ash as a soil amendment or a fill material in agricultural or landscaping systems. Previous research has identified several benefits of the use of fly ash as a soil amendment including providing plant nutrients, neutralizing soil acidity, and increasing water holding capacity of coarse textured soils. One of the main concerns about the usc of Oy ash as a soil amendment is the significant concentrations oftracc metals present in the ash, including arsenic (As). The objective in this study was to assess changes in As availability to the environment due to alterations in fly ash Nld soil chemical properties following natural weathcrin! of fly ash and ash-amended soil. Quantification of water soluble As, soil test (Mehlich 1) and oxalate extractable As, total As, and As considered to be associated with fly ash or soil fractions as defined by a fractionation procedure, provided estimates of how much As is available from fly ash and ash-amended soils. Comparisons of these forms of As before and after natural weathering indicate changes in the primary fly ash or soil fractions with which the As is associated and therefore changes in the amount of As available for release to the environment.

J.A. Shirey, (302) 831-2882

Spectral and PbvsjoJQeical Characteristics of Soybeans Grown Under Different Air QUAlity Environment. E. LEBLANC·, C.S.T. DAUGHTRy2 and C.L. MULCHI*, ·Univ. of Maryland, 2USDA­ARS, Remote Sensing & Modeling Lab.

In the context of global climate change, carbon dioxide (C02) levels are expected to rise steadily. Tropospheric ozone (03) concentrations are also expected to increase. These gases are altering the physiological responses of crops. In this study, the effects of CO2 and 0 3 on soybeans have been investigated using open-top chambers. Spectral parameters such as leaf and canopy reflectance, and leaf area index (LAI) have been measured periodically, while physiological variables such as gas exchange, chlorophyll concentration, and yield were also determined. Results indicate that leaf reflectance is not a reliable predictor of plant responses. However, LAI showed a closer relationship with canopy reflectance. Possible factors affecting these variations will also be presented and discussed. Spectral characteristics have to be interpreted carefully for prediction of crop physiological responses to CO2 and 0 3,

C.L. Mulchi, (301) 405-1328

Role of Antioxidant Enzymes in the Tolerance of Soybean cultiyars to Ozone Air Pollution. T. CHERNIKOVA. C.L. MULCHI*. Univ. of Maryland. E.H. LEE. and J.M. ROBINSON. USDA-ARS.

This study examined OJ tolerance mechanisms in two soybean cultivars (Glycine max L.). The plants were grown under low (24.2 nL'L-1 2-year seasonal average) and high (62.9 nL'L-1

) OJ levels in open­top chambers in the field during the 1994 and 1995 growing seasons. CUltivar 'Forrest' had more oxidative leaf damage and greater yield reduction under elevated 0, conditions than cultivar 'Essex'. There were no changes in stomatal conductance explaining a high 0, sensitivity of 'Forrest'. Ozone tolerance of cultivar 'Essex' appeared to be associated with enhanced activities of glutathione reductase, cytosolic ascorbate peroxidase. and CU,Zn-superoxide dismutase.

C.L. Mulchi, (301) 405-1328

6

Soil Moisture Water Use Efficiency Carbon Isotope Discrimination allu Leaf Gas Exchange of Bush Bean (Phaseo/lls vulgaris Ll

M. Raeini Sarjaz·, N.N. Barthakur, and PJ.H. Jones, Univ. of McGill.

Water-use efficiencies for the whole plant (WUI;) and single leaves (WUEJ were studied in a greenhouse as a function of soil moisture during four phenological stages of bush bean growth. WUE, increased significantly with soil moisture stress and attained its maximum value before the flowering stage. ~ and WUEj were linearly related (r = 0.92). WUEj was correlated with the transpiration rate (r = -0.87), stomatal conductance (r:::: - 0.80), and photosynthesis rate (r = 0.81). Carbon isotope discrimination, fl, decreased as soil water content decreased, and fl was correlated with both ~ (r = - 0.92) and WUEj

(r = - 0.88). There were significance differences among water regimes for leafN.

M. Raein Sarjaz, (514) 453-4267

WEDNESDAY, 16 JULY Sec. 3A-I-Forage Management

SeedUng Development of Pasture Herbs and Grasses. M.A. SANDERSON·. J. EVERHART, and G. EL WINGER. USDA-ARS Pasture Syst. and Watershed Mgmt. Res. Lab., University Park, PA 16802.

Establislunent of seedlings is a critical phase in pasture production. Seedlings are particularly wlnerable to water stress until root numbers and mass are sufficient to tap deeper soil moisture and support transpiring leaves. We compared the seedling development rates of 'Gala' and 'Matua' bromegrass (Bromus catharticus L), 'Pennlate' orchardgrass (Dactylis g/omerata L.), 'Puna' chicory (Cichorium intybus L.), and 'Tonic' and 'Lancelot' grazing plantain (Plantago lanceolata L.) for 7 wk in the greenhouse. Shoot and root developmental stage, length, and mass were measured weekly. Gala and Matua bromegrass and Puna chicory seedlings were larger (0.57 g vs. 0.34 g total shoot and root dry wt) and developed more rapidly than other forages. Gala bromegrass had more tillers per plant and fewer leaves per tiller than Matua. Puna chicory developed the largest root mass because of its strong taprootedness. Seedling size and development rate were positively related to seed mass.

M.A. Sanderson. (814) 865-1067

Measuring Pasture Legume Content Using Digital Color Analysis. E.B. RAYBURN·, J. LOZIER, D. JOHNSON, and W.B. BRYAN, West Virginia Univ.

Legumes in forage stands have a major effect on yield and quality. Measuring legume content is essential to understanding treatment effects but is time consuming. The use of digital analysis may reduce the time required. A 46 em quadrat was place on a mixed grass-legume sward and an image recorded using a HiS camcorder. Forage within the quadrat was clipped and legume content measured by hand separation. Video images were converted to computer graphic files and the images' red, green, and blue color intensity were measured over 20 ranges using digital analysis software. Color ranges that best estimated legume content were selected using stepwise multiple regression. The sm for legume content was 179 g kg·l. Only green color ranges were needed to predict legume content in this preliminary study. The regression of color intensity against legume content resulted in a R2 of 0.89 and regression sm of69 g kg,l. To estimate legume content within 100 g kg,l, if calibration is needed for eacl field digital analysis can save 1-7 hours but if one calibration can be used across fields it can save 6-20 hours per field after calibration.

E.B. Rayburn (304) 293-5229

NORTHEASTERN BRANCH ABSTRACfS

COrn/Alfalfa Rotations for Pennsylvania oai(,\' Operations G. W. ROTH·, R. A. KYPER, A. A. HOWER, and J. K. HARPER. Penn State University.

Shorter com/alfalfa crop rotations on dairy farms can lead to reduced use of soil insecticides, less need for fertilizer N and higher com and alfalfa yields. This project has focused on quantifying factors that can affect the economi~ of adopting shorter (3 yr com/3yr alfalfa rotations). Two commercial dairy operations were identified in Lycoming and Franklin counties in Pennsylvania. Key economic and agronomic information collected on each fann included crop rotation budgets, alfalfa stand counts, alfalfa yields, alfalfa root rot ratings and com rootworm beetle counts. Alfalfa yields of 4th year alfalfa averaged 0.9 TI A less than 3rd year alfalfa fields. Com rootworm beetle counts were above threshold on all of the 3rd and 4th year com fields in Franklin County, but only on one field in Lycoming County. Alfalfa stand counts were generally lower and root rot ratings higher for 4th year alfalfa compared to 3rd year Helds. Using yield and input data from the participating farms, the most profitable rotation on both farms was a 3yr coml3yr alfalfa rotation with the first year of com double cropped after the first cutting of the 4th year of alfalfa. The next most profitable rotation was the 3yr corn/3yr alfalfa rotations followed by longer comlalfalfa rotations. Lower com and alfalfa yields and higher input costs were the primary cause of reduced profitability of longer rotations.

G.W. Roth, 814-863-1018

Characteristics of ComlAlfalfa Rotations on Daiey Fauns in Two PeMsylyanjaCounties R. J. KESSLER·, T. B. MURPHY AND a.w. ROTH. Penn State University.

Many factors influence the optimum com/alfalfa rotation for a dairy farm. Similarly, the potential to shorten comlalfalfa rotations and realize the potential benefits of this practice is dependent upon producer practices such as the use of soil insecticides on fllSt year com, use of N credits from the alfalfa rotation and the success of establishing alfalfa. To estimate producers attitudes and practices on these and other related topics, a survey was conducted on 400 representative dairy producers in Franklin and Lycoming Counties, Pennsylvania. Responses were obtained from ISO producers who fanned a total of approximately 30,000 acres. Responses from the survey will be useful for the development of extension programs relating to the effective use of crop rotations as a component of integrated pest management on dairy farms in Pennsylvania. The results of this survey will be discussed in this paper.

R.J. Kessler, (717) 263-9228

Using Ie Blend® Seed in Higb Oil Com Production P.R. THOMISON·, A. GEYER, T. KRILL, L. LOTZ, and H. SIEGRIST, Ohio State University

The TOPCROSS~ grain production system may minimize the yield disadvantage associated with conventional high oil hybrids as well as enhance grain nutrient quality. A mixture of two types of com seed, designated a TC BLEND®, is used to produce high oil TOPCROSS grain. Field studies were conducted in 1995 and 1996 to compare the agronomic performance of a set ofTC BLENDS and normal com hybrids and determine the nutrient composition ofTOPCROSS grain. Strip plot tests were planted in five Ohio counties and a replicated plot test was planted at Hoytville in northwest Ohio. Grain yields of certain TC BLENDS were comparable to normal com hybrids. TOPCROSS grain produced by TC BLENDS exhibited consistently higher oil levels than grain from normal hybrids (7.1 % vs. 4.2% on a dry wt. basis). Oil yields of the TC-BLENDS were more than 60% greater than the normal grain parents. TOPCROSS grain moisture at harvest was usually higher compared to normal com but stalk quality was comparable for normal hybrids and TC BLENDS.

P.R. Thomison, (614) 292-2373

NORTHEASTERN BRANCH ABSTRACTS

WEDNESDAY, 16 JULY Sec. 3A.2-Forage Fertility Program

Yield Response of Alfalfa (Medicago sativa L.) to Additional Applications of Potassium on High Potassium Testing Soils. W.S. HARKCOM* and D. B. BEEGLE. Pam State Univ.

A study was conducted during 1991 and 1992 to determine whether alfalfa would exhibit a yield response to potassium fertilizer on fields with high soil potassium levels. even though soil test recommendations did not call for additional potassium fertilizer. The study included seven sites where initial soil potassium levels ranged from 0.142 cmol kg-1 to 0.522 cmol kg-I. Soil potassium fertility levels at some sites were due primarily to manure applications, while other sites had no manure history. Differences in yield. plant potassium uptake. and soil potassium levels between fertilized and unfertilized plots were measured. No significant yield responses were measured where soil potassium levels were above 0.183 cmol kg-I. Plant potassium uptake ranged from 16.3 g kg-Ion the unfertilized plots to 36.2 g kg-Ion the fertilized plots. Changes in soil potassium levels in the soil profile from 1990 to 1992 indicated significant differences in the 0-15 cm depth due to the fertilizer treatment and that most of the potassium removed from the soil occurred in the top 30 cm of the soil.

W.S. Harkcom. (814) 692-7955

Potassium Management of Grass for Dry Dairy Cows. J.H. CHERNEY·, DJ.R. CHERNEY, W.S. REID. and L.W. HATCH, Cornell Univ.

Perennial cool-season grasses are well adapted to the northern U.S.A, but potassium (1<) content of grass forage is a major concern in regard to dry dairy cow nutrition. Our objective was to identify factors influencing K content of grasses, so that a grass management strategy could be developed. Separate experiments were conducted with several grass species and varieties under varying nitrogen fertilization and harvest management regimes. Concentration of K in grass was influenced by grass species, grass maturity. time of season, and N and K fertilization. Orchardgrass (Dactylis glomerala L.) was consistently rugh in concentration of most elements, including 1(. while concentration of K was lowest in timothy (Phleum pralense L.). Grass regrowth was consistently lower in K content than primary spring growth. Nitrogen fertilization initially resulted in increased K content of forage if sufficient soil K was available, but available soil K was quickly depleted with high rates of N fertilization. Concentration of forage K decreased with increased N fertilization when soil K was low. due to dilution effects. Grass K content was reduced to as low as 8 g K kg-I dry matter.

J.H. Cherney, (607) 255-0945 jhc5@cornell.edu

Mixed Hayfield Response to Fertilizer and Manure Nutrients. E.M. Giberson, T.S. Griffin·, and M.H. Wiedeohoeft. University of Maine.

Soil fertility and forage productivity of mixed species, native hayfields is typically low, even though they could represent substantial nutrient sinks on dairy fanns 'with excess nutrient levels. Research was intiated in 1995 (2-yr duration) and 1996 (I-yr) to evaluate yield and forage quality response of a native hayfield to: control, N alone. NPK fertilizer. manure alone, and combinations ofNPK and manure. All non-control treatments recieved same N input. and N-P-K inputs were identical for NPK fertilizer and manure treatments. Yield always increased with nutrient application in any fonn, as did forage crude protein concentration, and N alone increased annual yield from 34 to 62% (increases of 1.2 to 1.8 ton DM/a). NPK fertilizer did not increase yield compared to N alone, although soil P and K levels were declining where only N was applied. Forage yield following using only manure nutrients was lower that NPK fertilizer in 2 of 3 site-years, but increased yield 20 to 46%, compared to control. Timing of manure application (first vs. second cut) did not affect forage yield.

T.S. Griffin 207-581-2942

Dairy Manure Avplied to Alfalfa, Grasses and Alfalfa­Grass Mixtures I Effects on soIl NItrogen and stand PersIstence. D.H. MIN, L.R. VOUGH* and T. 'CHEKOL. unlv. of Maryland.

The objective of the study was to evaluate rates of application of dairy slurry to established stands of alfalfa (lfedicago sativa L. ) (AL) , orchardgrass (Dactylis glomerate L.) (OR), tall fescue (Festuca arundinacea Schreb.) (TV), reed canarygrass (Phalaris arundinacca L.) (RC), AL-oR and AL-RC on soil NO',-N levels and stand peroistence. AL, OR, TF and AL-oR were cut 5X, OR, RC, AL-oR and AL-RC as 4X. Three manure application rates, 791, 1581 and 2016 kg total N ha" in the 4-cut system and 837, 1691 and 1933 in the 5-cut syotem were campared with 560 kg R from NU.No, and no N control. Soil Na,-N levels were significantly higher for RC than OR, AL-oR and AL-RC at the 1581 kg rate of slurry at depths of 0-30 and 31-60 em. At the 2016 kg rate, NO',-N was significantly higher for RC at the 0-30 em depth and for OR and RC at the 31-60 em depth. There were no meaningful differences among species in the 5-cut system. Levels were not significantly different in either system between the lowest rate of manure and 560 kg N from NH.No, at both deptho. The intermediate and high rates of slurry and NH.No, had a detrimental effect on AL and AL-oR stand densitiea in the 5-cut system.

L.R. vough, (301) 405-1322

Yield and quality of timothy (Phleum pratense L.) as influenced DY rate and trma of N fertilization. T. CHEROL*, L.R. VOUGH, and D.H MIN. Univ. of Maryland.

The common Maryland timothy N fertilization practice of 67-96 kg R ha" in Feb-March + 34-67 kg N ha" 1.mmediately after the 1st cutting or in early August do not seem to correspond to the seasonal growth characteriatics of timothy. This experiment was designed to evaluate rates (0, 67, 101, 134 and 168 kg N ha") and frequency (split vs. single) of nitrogen fertilization on yield and forage quality. A oimUar experiment comparing single late winter applications of 0, 67 and 134 kg N ha" was also conducted on a producer's farm. Results from both experiments indicated a significant increase in yield at the 134 kg N ha" application rate. There were no significant yield dlfferences between split and aingle applications of the same nitrogen rates. Higher rates of nitrogen resulted in a concomitant increase on the crude protein levela of the first cutting. Rate and time of N fertilization had no significant effect on acid and neutral detergent fiber contents.

T. Chekol, (301) 405-1325

Fall and Spring Responses of Tal! Fescue to Fertj!jzer N Applied in Fall.

7

I.A BALASKO·. S.L. HYPES, and E.H. SKILES. West VU'ginia Univ.

Studies were designed to provide data from which recommendations could be made about the efficient use ofN fertilizer to extend the grazing season of tall fescue (Festuca arundinacea Schreb.) pastures into late fall, winter, and early spring. In one experiment, nitrogen was applied in late summer at rates ranging from 0 to 336 kg ha-l over an 8-yr period. Forage was harvested in October or November and again in Mayor June. In this experiment, negative rnar8inal productivities were observed at N rates above 269 kg ha-I in both fall and spring. Nitrogen rates resulting in high returns per hectare ranged from 45 to 135 kg. In another experiment, split applications ofN were applied in factorial combinations ofO. 67, 134,202, 269, and 336 kg ha·1 in late August or early September and 0, 67, 134, or 202 kg ha·1 in February of the succeeding year. Data from this experiment suggested that fertilization with 134 kg ha·l in mid-late summer and again in February resulted in near maximum seasonal yields, mid-December yields, and early spring yields. In both experiments. forage CP concentrations at all N rates were well above NRC recommendations for beef cattle and sheep.

lA. Balasko, (304) 293-6256

8

Development and Implementation of the Northeast Pasture Research and Extenslon Consortlum. C.R. KRUEGER', Pennsylvania State Univ., and H.B. PIONKE, USDA-ARS.

This newly established Consortium involves all the land­grant universities in the Northeast Region and the USDA/ARS Pasture Systems and Watershed Management Research Laboratory at University Park, Pennsylvania. The mission is to link livestock graziers and federal, state, land-grant, and private research and extension groups into partnerships that will identify, develop, and promote pasture research and extension leading to economically, socially, and environ­mentally sound and sustainable grazing-based livestock production systems for the Northeastern U.S. The membership includes approximately one-half public sector and one-half private sector individuals. The group is representative geographically, multi-disciplinary, multi-functional (research and extension), and includes producers, a banker, and other agri-business persons. The Consortium objectives and 10ng- and short-term goals will be presented. The role of public-private partnerships in providing relevance and accountability for research and education programs in the Northeast Region will be discussed.

C.R. Krueger (814) 865-6541

Blue light inhibits stomatal deyelopment ora soybean isoline which prodUces a unique flavonoid glycoside K9 L. LlU and S.J. BRITZ. Climate Stress Lab, USDAIARS

Stomata have a fundamental role in controlling plant photosynthesis and transpiration. Although factors controlling stoma development are poorly understood, a line of soybean has been identified that contains a specific flavonol glycoside, kaempferoI3-0-2-glycosyl-gentiobioside (K9), as well as gready reduced stomatal density (especially on the upper epidermis). In addition, this isoline has lower photosynthetic rate and dry matter accumulation (Buttery and Buzzell, Plant Physiol. 85:20,1987). We treated the plants with various irradiances and qualities of lighting in growth chambers. Our results showed that growing the isoline with K9 under lights lacking blue wavelengths results in stomatal densities similar to the isoline lacking K9. Addition of low levels of blue light causes ca. 50% reduction in stomatal density and stomatal conductance on the upper epidermis of the K9 isoline. In contrast, the line lacking K9 increased stomatal density by 17% at the same level of blue light Morphological observations revealed undeveloped meristemoids at various developmental stages in mature leaf. Additional experiments are underway to quantify and localize flavonoid glycosides. The relationship between light, stomatal development and flavonoid functions will also be discussed.

L. Liu, (30 I) 504-6526

WEDNESDAY, 16 JULY Sec. 3D-I-Natural Resources Management

Maryland Soils and the UMCP Soil Monolith Collection. D.S. FANNING· and M.C. RABENHORST, Univ. ofMmyland, College Park.

Maryland: America in Miniature. Our soils and landscapes span the range from the tidal marshes of the Coastal Plain thru those on highly weathered igneous and metamorphic rocks in the Piedmont to those over sedimentaJy rocks of various kinds in the Appalachian Mountains. Soils go from old well-fonned Ultisols, thru Alfisols, Spodosols and Histosols to baby Entisols and adolescent? InceptisoJs including acid sulfate soils in geologically old (e.g. Tertimy) and modem (e.g. dredged) sediments. This range of soils includes highly productive agricultural soils, as well as those with varying degrees of agricultural and envirorunentallimitations including Hydric soils ofwetlands. Monoliths of MaJyland soils and some from elsewhere (e.g. Kansas and Washington. DC) are displayed in the basement ofH. 1. Patterson Hall. A geographically arranged exhibit in the old wing of the building was started in 1953 by Dr. G. A Bourbeau. New (1994) monolith cases in the new (1967) wing of the building have several special displays that will be mentioned. A soil petting zoo may be opened by the time of the NEBASA meetings. We invite you to indulge.

D. S. Fanning, (301) 405-1344

NORTHEASTERN BRANCH ABSTRACTS

Predicting Phosphorus Desorption from Irish Agrirultwal Soils' Applications o(Soi! Testing to Water Quality Prptr.djon. N.J. LUKA·, J. T. SIMS, Univ. o(Delaware, and H. TUNNEY, Teagasc Environmental Research Centre, Republic of Ireland.

In 1996, a research project (ocusing on agricultural P and surface water quality was initiated between the University of Delaware's Plant and Soil Science Department and Teagasc, the Irish agricultural and environmental research agency. The goal of this project is to develop improved soillesting practices that can identify soils with a high potential for P loss in erosion and runoff. Eutrophication of surface waters is a major environmental issue today in Ireland, where inputs o(P to (anus often exceed outputs. The Irish climate, topography, and agricultural practices combine to enhance the likelihood of P transport from soil to water. Establishing quantitative, predictive relationships between soil test P and potentially desorb able P could be extremely useful in efforts to prioritize nonpoint source pollution control efforts within Ireland's environmentally threatened watersheds.

N.J. Luka, (302) 831-2882

Real-Time SOil Water Qynamjcs Using MuHisensor Capacitance Probes' Laboratorv Calibration and Beld Use I. C. PALTINEANU· and J. L. STARR, USDA-ARS, BARC, Environmental Chemistry Laboratory, Beltsville, Maryland.

The objectives of this research were to assess the characteristics of a newly developed multisensor capadlance probe. to calibrate the sensors against a Mattapex silt loam soil, and to use the probes and the monitoring system In an experiment involving conventional- and no-tillage methods on com. A highly significant (r=0.992 for n=15, and RMSE=0.009em'em·' water, nonlinear (9y= 0.490SF2-'874) relationship was found between the soil volumetric water content (9, an'em-3) and scaled frequency (SF). The SF = (Fa - Fs) I (Fa - Fw) represents the ratio of individual senso'" s frequency in soil (Fs) compared with that inside of the PVC pipe surrounded by air (Fa) and surrounded by nonsaline water (Fw) at room temperature ( ... 22°C). Axial and radial sensitivity studies showed that these capadtance sensors give integrated readings over a primary depth interval of 1 Oem, and a radial capacitance fringe within 10 em of the access pipe. By design, the probes can measure soil water content as deep as 15m., with the probes located at distances up to 500 m from the data logger. Our calibration studies Indicate that these multisensor capacitance probes, and the data logging system can be used to accurately measure volumetric soil water content with a soil water monitoring system. Field installation and micro and macroscale differences between tillage methods will be presented using 10mln. time intervals for the 10. 20, 30, and 50em. soil depths.

J. L. Starr, (301) 504-6888

WEDNESDAY, 16 JULY Sec. 3D-2-Cropping Systems & Sustainable

Agriculture

Top and Root BiomasS of 10 Coyer Crop Species' Effects of Planting Date and Nitrogen Application. J. MT.PLEASANT* and R. F. BURT, Cornell University.

A field experiment in Ithaca, NY examined the effects of cultural practices on root and shoot dry matter (OM) of ten cover crops. Seeding dates (July vs August) were main plots; species (canola, crimson clover, oat, rye, annual fescue, bromegrass, fescue, perennial ryegrass and a mixture of ryegrass and red fescue) were sub-plots; and nitrogen rates (23 kg ha·1 vs 57 kg ha·l) were sub-sub-plots. DM was measured in late Fall '94 (December) and early Summer '95 (July). At both sampling times cover crops seeded at the early seeding date produced much greater top (5300 kg ha' vs 1604 kg ha·l) and root biomass (1037 kg ha·1 vs 455 kg ba·l) than s~ies seeded later. Oats produced the highest top DM in the fall, (7720 kg ha·l) but rye~s & fescue produced the greatest at the summer sampling (13788 kg ha· I

). Perennial ryegrass produced the most root DM in fall (1079 kg hal), while fescue had the most in sununer (2931 kg ha'l The higher nitrogen rate increased top DM (3840 kg ha·1 vs 3063 kg ha' ) in the fall sampling, but the effect was more pronounced at the early seeding date. A similar pattern was found at the July sampling date. Nitrogen had no effect on root growth at either sampling period. There were significant interactions between species and date, species and nitrogen, and date and nitrogen.

J. Mt.Pleasant, (607) 255-5991

NORTHEASTERN BRANCH ABSTRACI'S

Njtrneen Management for Grain Sorehum Based on CfOl!pin~ System. R.W. Taylor·, B. Uniatowski, B.L. Vasilas, and J.D. Pesek, Univ. of Delaware. Farmers are under increasing pressure to use the minimum amount of fertilizer needed to reach maximum economic yield (MEY) levels. Eight studies (a combined tota1 of 36 year-envirorunents) were conducted from 1986 to 1994 to evaluate the response to single and split applications of various rates of nitrogen (N) of grain sorghum grown in rotation with another non-legume grain crop (dryland com or grain sorghum), with soybeans (Glycine max), or no-till following a winter cover crop of vetch (Vicia spp.). MEY for grain sorghum grown in rotation following a non-legume grain crop was at 56 kg N hal applied either at or shortly after planting or split in two applications, one at planting and one at the 5-leaf stage. Dryland studies for grain sorghum grown in rotation following soybeans or after a winter vetch cover crop indicated little response to N applications and a MEY of from 0 to 28 kg Nha- I .

R.W. Taylor, (302) 831-1383

Amending Atlantic Coastal Plain Soils to Reduce Agrjcultwal Nonpoint Ploss. D.M. DYSON, P.A. VADAS· and J.T. SIMS, Univ. of Delaware.

Southern Delaware is home to a poultry industry that imports phosphorus (P) in feed and disposes of waste poultry litter through application to agricuitmaJ cropland. Many agricultural soils in southern Delaware test high or excessive in P from years of litter applications that add P to soils in excess of crop needs. Because P from crop production has been identified as a nonpoint source pollutant in Southern Delaware's surface waters, it is essentiaJ to prevent P losses from high P agricultural soils. Our objective in this study was to assess the effect of amending two high P soils with an iron (Fe)-rich by-product on P desorbability and extractability from the soil, and the soils' P sorption capacity. We amended two high P soils with a stabilized and unstabilized Fe-rich by-product at rates of 0, 12.5,25, SO, and 100 g/kg soil. We incubated the amended soils at field capacity and room temperature and anaJyzed them at 7, 21, and 49 d for pH, readily desorbed P (RD-P). Meh1ich-1 extractable P (M I-P), and a P sorption index (PSI). At eaclt sampling time, amending the soils typically increased pH and PSI, and decreased RD-P and MI-P. At each amendment rate over time, pH remained constant. RD-P and M I-P remained constant or decreased slightly, and PSI increased. The data show that amending the soils may prevent P losses by decreasing P desorbabiJity and extractability and increasing soil P sorption capacity.

P.A. Vadas, (302) 831-2882

The GWBE Project· Soils and the Environment in a Science-Education Partnership. E.R. LEVINE-, NASA/GSFC

Soil science is an important component of the GLOBE (Global Learning and Observations to Benefit the Environment) project. GLOBE is a worldwide network of K-12 grade students, teachers, and scientists working together to increase environmental awareness of individuals throughout the world; help students reach higher l~vels of achievement in science, mathematics, and technology; and proVIde a soun:e of data for scientific research. As of April 1997, over 3,500 schools in 51 countries have registered to participate in GLOBE. Measurements and activities are being designed by scientists to teach students how to collect data on soil properties, land cover and biometty, water chemistty, atmosphere/climate, ultraviolet radiation, trace gases, and GPS location. To characterize the soils, students take samples from a soil pit, and describe key chemical and physical propenies of the soi! profile. They also measure weekly soil moisture and temperature. Soli protocols are being designed at NASA's GSFC (in cooperation with USDA NRCS), and at the University of Arizona.

E.R. Levine, (301) 286-5100

Moving Moldova towards a Sustainable Agriculture' I. Cropping Systems Management. I.F. HOLDERBAUM, AM. DECKER, and RL. ~., CH2MHiIl International Services, Inc. & Univ. of MD.

9

Moldova, one of the newly independent states of the fonner USSR, presently utilizes arachic cropping systems imposed by the USSR An objective ofa US­AID funded project in Moldova included educational effons to make fanners and agricultural policy planners aware of more efficient cropping systems. Current rotations do not match the crops to soil types or landscape positions. The preceding crop is not efficiently used in terms of nitrogen availability or pest control. Presently. winter wheat foUows alfalfa while com follows either Stmflower or tobacco. Agronomic and hortirultural crops include winter wheat and com (4QO/o), &mftowers (8%), sugar beets (5%), fodder crops (16%). and grapes and orchards (21%). With the ecception of winter cereals, all crops are spring seeded. Planting alfalfa in late summer following a small grain is not considered although doing so would likely improve yields. Consideration of no-till renovation of pastures and planting of small grains and alfalfa in existing crop residues could help invigorate existing systems.

RL. Hill, (301) 405-1347

Moying Moldoya towards a Sustainable AgrjcytJure' II Conservation Tillace Technology. J.F. HOLDERBAUM, R.L.IllLL· and A.M. DECKER. CIUM Hill International Services, Inc. & the Univ. of MD. Moldova,

one of the newly independent states of the former USSR. suffers tremendous erosion losses that threatens their environment and long-term agricultural sustainability. One objective of a US-AID funded project within Moldova was to introduce conservation tillage technology and educational programs to address erosion concerns relating to agricultural sustainability. Conservation tillage technologies were demonstrated within three different geo-climatic Mo~dovan regions. A series of seminars and workshops were also conducted stressmg the benefits of crop residue management on soil losses, moisture conservation, and economics. The conservation tillage technology resulted in such significant fuel, time, and labor savings in 1996 that its acceptance was almost too complete in that it was felt the implements, in themselves, would solve all problems. In reality. use of this technology creates a whole new set of management challenges. The introduction and demonstration of these technologies have provided a basis of consideration for fundamental changes in Moldovan agricultural production systems.

R.L.HiII,(30 I) 405-1347

Additional Abstract Sec. 2A·l

Potential andEconomic Yiability of Inuoducjna Tm (mps Into We» Yiuinja Pa»urn. L O. ANYAHA, • W. B. BRYAN and E. B. RAYBURN, West Virginia Univ.

A study was conducted to propose and Konomial~ mluate different tree management regimes and silvipastoral syst!ms. Four tree aops, black walnut, (hinese chestnut, black locust, and honey IMust were selected based on their ability to adapt to a mUltiuopping (ramework. The tree crops are valued (or their _, nuts (pods), and abaity to encourage under story growth. five different management regime.s, producing various combinations of timber, nuts, and grazing were pr~posed. Each tree sepa~tely or In

combination with livestock and livestock separately provided a productIon system (er each regime. Black walnut, black locust. and honey locust production systems were studied under both the timber and timber and grazing regimes and h/ack walnut, CIIinese chestnut, .. nd honey locust were considered in the nut producing regimes. The regimH were mluattd in tfrms of int!mal rate of return (I RR) and net present value (NPY). Intmlal rat!s of return from timber to timber, nuts, and grazing, ranged from 5.9 to 26.7. Timber, nuts, and grazing also had the highest NPV of S758 and $677 (or black walnut and honey locust, respectively. Howmr, Chines! dlestnllt had the highest HPV in the timber and nuts ~me. It was (ound that nuts and pods added return to the timber regime. Grazing also a~ded ~neftU I~ term~ of I~ and NPY to the timber and nuts regime. The results showed that the most IntenslYe muluuopprng regime -timber, nuts, and grazing· provided the greatest return on investment. Research needs rel~~ to tree production, such as tree cultivation, energy production, silviculture and planting stock, sdYlpastoral systems, economics and marketing were examined in this paper.

L O. Anyama, (301) 405-1326