Rising concerns about greenhouse gases, increased fuel prices, and the potential for new high value agricultural products have raised interest in the use of maize stover for bioenergy production. However, residue harvest must be weighed against potential negative impacts on soil quality. This study, conducted in Chazy, NY, evaluated the long‐term effects of 32 yr of maize (Zea mays L.) stover harvest vs. stover return on soil quality in the surface layer (5–66 mm) under plow till (PT) and no‐till (NT) systems on a Raynham silt loam (coarse‐silty, mixed, active, nonacid, mesic Aeric Epiaquept) using physical, chemical, and biological soil properties as soil quality indicators. Twenty‐five soil properties were measured, including standard chemical soil tests, aggregate stability (WSA), bulk density, (ρb) penetration resistance (PR), saturated hydraulic conductivity (Ks), infiltrability (Infilt), several porosity indicators (aeration pores(PO > 1000), soil water potential = Ψ > −0.36 kPa; air‐filled pores at field capacity (PO > 30), Ψ > −10kPa; available water capacity (AWC), −1500 < Ψ < −10 kPa), total organic matter (OM), parasitic (Nemparasitic) and beneficial nematode (Nem beneficial) populations, decomposition rate (Decomp), potentially mineralizable N (PMN) and easily extractable (EEG) and total glomalin (TG). Only eight indicators were adversely affected by stover harvest, and most of these effects were significant only under NT. Almost all indicators affected by stover removal were affected equally or more adversely by tillage. A total of 15 indicators were adversely affected by tillage. Results of this study suggest that, on a silt loam soil in a temperate climate, long‐term stover harvest had lower adverse impacts on soil quality than long‐term tillage. Stover harvest appears to be sustainable when practiced under NT management.

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Soil water management practices may affect crop growth by reducing periods of excess or shortage of soil water. The objective of this study was to evaluate forage yield and quality as affected by soil hydrologic conditions imposed by four water management practices. The experiment was conducted on a Muskellunge sandy clay loam soil (fine, mixed, frigid Aeric Ochraqualf) in northern New York during three growing seasons (1989–1991), each involving three cuttings of an alfalfa (Medicago sativa L.)—timothy (Phleum pratense L.) intercrop. Treatments consisted of (i) drain open at all times (OD); (ii) drain closed at all times (CD); (iii) drain open in winter, closed in summer (SC); and (iv) drain open in winter and the water table at a target 0.6‐m depth using a weir and supplemental irrigation in the summer (SW). Lack of drainage under CD resulted in longer periods of soil saturation and reduced yields by 9 and 16% compared with OD in the first and second growth cycle of 1990 and by 17% during the first growth cycle of 1991. Increased soil wetness after drain closure under SC did not result in yield increases compared with conventional drainage during dry periods and caused a small decrease during a wet growth cycle. Maintaining a water table at 0.6‐m depth resulted in 30% yield increase in the dry year 1991, but none in 1989 and 1990. Soil temperatures were not affected by water management. When yields were reduced, crude protein and elemental (P, Ca, K, Mg) concentrations were generally higher, and fiber and lignin levels were generally lower, indicating that increased forage quality partially compensates for lower yields, especially under excess water conditions.

Synopsis Alfalfa irrigated with 3 inches of water whenever available soil moisture to an 18‐inch depth was 60, 40, 20, or 0% produced relative yields of 100, 81, 63, and 37%. Moisture absorption was greatest in upper 6 inches of soil and decreased when available soil moisture dropped to 25 to 30%. Below 15% available soil moisture, plants showed moisture stress and rate of stem elongation dropped almost to nil. Similar water efficiency in production of top growth, decreased production, and rate of stem elongation as soil approached the permanent wilting point indicates that water is not equally available between field capacity and permanent wilting point.

A cropping problem was assigned in association with crop management courses at Cornell University and the University of Massachusetts, and a pasture management course at Texas A&M University. The objectives of the problem assignment were to encourage students to apply subject matter of the course towards development of a cropping or pasture plan and to motivate students to use outside and reserve readings.A detailed soils map, soil test results, climatic summaries, a visit to a subject farm, statements concerning management history and potential pest problems, and an explicit outline of requirements were among the informational inputs that were made available in association with the cropping problem assignments.The problem required a detailed annual cropping or pasture plan, including establishment, fertilization, weed and insect control, harvest, and storage practices. The pasture plan required a diagram of fence and water locations, and details of forage utilization by grazing livestock. A general 5year plan of crop sequences, or pasture plant sequences and livestock inventories, was additionally required, besides the annual plan, at Massachusetts and Texas A&M, respectively.Of students who responded to multiple-choice evaluative statements at Massachusetts and Texas A&M, 59 to 100% agreed or strongly agreed that the cropping or pasture problem exercise was worthwhile and contributed to their understanding of the subject matter. Of the responding Texas A&M students, 62% thought the pasture problem was a realistic exercise and 57% agreed or strongly agreed that lecture and textbook materials were made more meaningful by the problem. Nearly half of the Texas A&M students agreed that the effort required to complete the plan was appropriate, and 38% thought extension publications were the most useful source of information for the effort.Sixty percent of the Texas A&M students who developed a management plan with two or three other students thought that interaction with other students was a desirable approach to learning. An increase in student-instructor interaction, apart from regular lectures, also resulted from the cropping problem assignments at Texas A&M and Massachusetts.Additional index words: Cropping plan, Pasture plan, Management plan, Problem format, Student evaluation, Group problem solving. 'Contribution of Dep. of Soil and Crop Sciences, Texas A&M Univ., College Station, TX 77843. 'Assistant professor, Dep. of Soil and Crop Sciences, Texas A&M Univ.; and professor,