Cropping systems for minimum or no tillage have been developed to produce corn (Zea mays L.) yields equal to or higher than yields obtained in conventional tillage systems, but limited research has been conducted with tillage systems involving corit and soybean [ Glycine max (L.) Merr.J rotations. The objective of this study was to compare different cropping sequences of corn, soybean, and wheat (Triticum aestivum L.) in conventional, strip, and no tillage. A field experiment was conducted on a Hartsell fine sandy loam (fine-loamy, siliceous, thermic Typic Hapludults). In 1981, corn yields with no tillage were 30o/o lower than those from conventional tillage systems. No corn yield differences were observed in 1982 and 1984 due to tillage or crop rotation; however, in 1983, strip and no tillage in conjunction with soybean in the rotation increased corn grain yields by 12%. Soybean yields in strip and no tillage decreased 16o/o compared to conventional tillage yields in 1981, but in subsequent years, soybean yields increased with those systems. A significant tillage x rotation interaction in 1981, 1982, and 1983 was caused primarily by a buildup of soybean cyst nematode (Heterodera glycines Ichinohe) (SCN) population with conventional tillage and continuous soybean. Rainfall affected soybean yields more with conventional tillage than with strip or no tillage. The conservation tillage systems (strip or no-tillage system) in combination with corn-soybean rotation for both full-season or double-cropped soybean gave the most consistent yield increase for the 4 yr.Published in Agron. J. 80:76-80(1 988).

Broiler poultry litter was deep-stacked (2-5 m high) in three ways: (1) uncovered, (2) covered with 0-1524 mm clear polyethylene and (3) surface-watered to form a 2-5 cm crust upon drying. After 30 days, each litter was used to formulate two diets containing proportionately 0-25 or 0-50 poultry litter (dry-matter basis). Urea was used as the nitrogen source in the control diet. All diets contained 100 g/kg cottonseed hulls, 20 g/kg limestone and cracked maize. Each of the seven diets was offered to 12 crossbred steers (two pens per diet; initial body weight 204 kg) for 84 days. Blood was collected and body weights measured every 28 days. After 84 days, liver biopsies were obtained from four steers per diet and an additional three steers per diet were penned individually and nutrient apparent digestibilities were determined. Steers gained 1-6 kg/day on the urea diet and 1-2, 1-3 and 1-2 kg/day on the diets containing 0-25 litter, uncovered, covered or watered, respectively. Steers consuming the 0-50 litter diets gained 1-0,0-9 and 1-0 kg/day, respectively (significant linear decrease; P < 0-01). Litter depressed (P < 0-04) apparent dry matter, organic matter and gross energy digestibilities regardless of stacking method. However, nitrogen apparent digestibility was decreased by uncovered and watered litter only. Increased proportion of litter in the diet resulted in increased serum sorbitol dehydrogenase and aspartate aminotransferase and liver copper concentrations (P < 0-07); however, clinical copper toxicosis (haemolytic crisis) was not observed. Dietary inclusion of broiler poultry litter also increased serum phosphorus and decreased serum calcium concentrations (P < 0-07). Covering deep-stacked litter preserved nitrogen quality, but improvements over uncovered litter were not of sufficient magnitude to elicit improved animal performance in this study.

Water was applied at flow rates of 0, 3.8 and 7.6 liters per hour (0, 1 and 2 gph) and nitrogen (N) was surface applied at 50, 100, 200, and 300 kg/ha (45, 90, 180 and 270 lbs/A) in 1981 and 1982 to Acer rubrum (L.). Tree height, trunk caliper and root dry weight within an AAN specified size were greater with trees grown with 3.8 l/h (1 gph) compared to non-irrigated trees. Tree height and trunk caliper were not affected by N rate. Nitrogen rate influenced root growth. Roots of red maples grown with 3.8 l/h (1 gph) and 200 kg/ha (180 lbs/A) of N were more concentrated under the tree.

Four woody nursery crops were grown for 3 years (1981–1983) in plots with varying pH levels. Greater growth of ‘Compacta’ Japanese holly and Foster's holly occurred in 1981 and 1982 at lower pH levels (4.1–5.8). However, Mn phytotoxic symptoms appeared on ‘Compacta’ Japanese holly dunng the fall of 1982. Foliar Mn levels of all 4 species exceeded 2500 ppm when grown at the lowest pH level, with the exception of Foster's holly in 1983. Growth of ‘Nellie R. Stevens’ holly was not affected by pH, while Taxus growth was enhanced in 1983 at the higher pH levels (4.7–5.9). Foliar nutrient concentration trends were similar among the 4 crops.

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