The largest portion of Alabama's rapidly growing poultry industry is geographically concentrated in the Sand Mountain region of northern Alabama. The result is that large amounts of waste are applied to relatively small areas of agricultural soils. A study was conducted to determine the effects of long‐term broiler waste (litter) application on environmentally related soil conditions in the region. The region has an average annual rainfall of 1325 mm, which is evenly distributed throughout the year, a thermic temperature regime, and soils in the region are of the Ultisol order. In each of four major broiler‐producing counties, three pairs of sites consisting of long‐term (15–28 yr) littered and nonlittered fields on matching soil series and maintained under perennial tall fescue (Festuca arundinacea Schreb.) were sampled. Soil cores were taken to 3 m or lithic contact and depth‐incremented samples (0–15, 15–30, and each subsequent 30‐cm interval) were analyzed for organic C, total N, NO3‐N, pH, electrical conductivity, and acid‐extractable P, K, Ca, Mg, Cu, and Zn. Litter application increased organic C and total N to depths of 15 and 30 cm, respectively, as compared with nonlittered soils, whereas pH was 0.5 units higher to a depth of 60 cm under littered soils. Significant accumulation of NO3‐N was found in littered soils to or near bedrock. Extractable P concentrations in littered soils were more than six times greater than in nonlittered soils to a depth of 60 cm. Elevated levels of extractable K, Ca, and Mg to depths greater than 60 cm also were found as a result of long‐term litter use. Extractable Cu and Zn had accumulated in littered soils to a depth of 45 cm. These findings indicate that long‐term land application of broiler litter, at present rates, has altered soil chemical conditions and has created a potential for adverse environmental impacts in the Sand Mountain region of Alabama.

The tropical legume 'Tropic Sun' sunn hemp (Crotalaria juncea L.) may have potential as an alternative legume cover crop or as forage for cattle in southern temperate regions. This study determined dry-matter production, chemical composition, and N release from sunn hemp residue under conventional and no-tillage systems as might be used in corn (Zea mays L.) production. Sunn hemp was sown in mid-August and mowed in early December on a Norfolk sandy loam (fine-loamy, siliceous, thermic Typic Kandiudult) and a Lucedale fine sandy loam (fine-loamy, siliceous, thermic Rhodic Paleudult) in Alabama (1991 1992). Mesh bags were used to determine residue decomposition and N release. Average dry-matter production was 5.9 Mg ha" 1 9 to 12 wk after planting. At mowing, residue N content averaged 126 kg ha~'. Residue overwintered on the soil surface until early April. During the first 4 wk following mowing, N release from residue was 50%. In April, N remaining in overwintered residue was only 38% of that after mowing in December (45 kg N ha' 1 ). Nitrogen release from residue during the subsequent corn growing season was 13% in no-tillage and 43% in conventional tillage. Sunn hemp produced sufficient dry matter to cover and protect the soil from erosion and provided sufficient N to benefit a succeeding summer crop. In addition, forage quality of leaves was suitable to provide late summer and fall grazing. Sunn hemp has potential to be managed as an alternative to winter legume cover crops in warm temperate regions.

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