Effects of Subsurface Litter Application Technology on Water Quality, Odor, and Corn Yield.
Arthur L. Allen1, Nancy Chepketer1, Ray B. Bryant2, 1Leonard Kibet, Eric B. May1, Robin Brandt3, Herschel Elliott3, Fawzy M. Hashem1, and Peter J. A. Kleinman2
1University of Maryland Eastern Shore, Dept. Agriculture, Food and Resource Sciences, Princess Anne, MD 21853; 2USDA-ARS, Pasture Systems and Watershed Management Research Unit, University Park, PA 16802; 3The Pennsylvania State University, Dept. of Agricultural and Biological Engineering, University Park, PA 16802.
KEYWORDS: Poultry litter, Chesapeake Bay, Water Pollution, Soil Amendments, Odor Management
Abstract
Impending rules in Maryland will require that poultry litter be incorporated into the soil upon application. For the past five years, we have tested various direct incorporation technologies for poultry litter on Maryland's coastal plain. Most recently, the USDA-ARS “Subsurfer” has been the focus of experimental and on-farm trials in and around the University of Maryland Eastern Shore. Here, we review our experience with the Subsurfer, including results of long-term agronomic and water quality trials, emissions testing, and performance concerns. On the positive front, we have documented increases in corn yields with subsurface application by as much as 25% and major reductions in ammonia and odor emissions, as well as, phosphorus in runoff. However, the effects of subsurface application on nutrient leaching have been mixed, influenced to some degree by experimental methods, and on-farm trials have not yet matched on-station results. Continued strong interest in this technology offer promise in addressing existing trade-offs.