Potential Nitrogen Mineralization in Sandy Soils under Long-Term Poultry Litter Management

Abstract Application of poultry litter to crops and pastures as an organic nutrient source is a common practice in U.S. agriculture. A laboratory incubation study for 60 days was laid out in a randomized block design. The treatments consisted of poultry litter applications corresponding to 3, 6, 9, 12, 15, 18, and 21 Mg ha–1 in addition to control. Accumulation of mineralized nitrogen (N) was observed in all the treatments, with a typical small increase in inorganic N during the first 3 days followed by a big flush between 3 and 5 days. Mineralized N ranged from 69% to 39% of the total N applied in the greatest to lowest application treatments, respectively. The results suggested that recommendations should emphasize partitioning the total litter into smaller installments to coincide with crop growth period. Also, long-term application of poultry litter was found to increase soil pH. Keywords: C:N ratioincubation studyN mineralizationpoultry litter managementsoil pH