Monday, November 5, 2007
119-2
Evaluation of Pre-plant Swine Effluent Application Methods for Corn Grain Production.
Jason Warren1, Karamat Sistani1, Scott Shearer2, and Steve Higgins3. (1) USDA-ARS, USDA-ARS, Animal Waste Management Research Unit, Bowling Green, KY 42104, (2) University of Kentucky, Biosystems and Agr Engineering 128 Charles E Barnhart Building, Lexington, KY 40506-0276, (3) Biosystems and Agr. Engineering, University of Kentucky, 128 Charles E Barnhart Building, Lexington, KY 40506-0276
A field experiment was conducted to evaluate three methods of pre-plant swine effluent application for corn grain production. The methods included surface application with no incorporation, direct injection, and application in combination with soil aeration. Mid-season tissue analyses and corn grain yields suggest that the direct injection and soil aeration application methods allowed for similar N utilization, which was improved compared to surface application of swine effluent. The concentrations of N in ear-leaves collected at mid-silk from treatments receiving injection and aeration applications of swine effluent at a rate of 236 kg N ha-1 were equivalent to that found in treatments receiving 185 kg of N ha-1 at side-dress as inorganic fertilizer. In contrast, the ear-leaf N content of the treatment receiving surface applied swine effluent at an equivalent rate was not significantly elevated above the control treatment, which received no N fertilizer. The improved N utilization resulting from the injection and aeration application of swine effluent likely resulted from decreased NH3 volatilization from these treatments. This improved N utilization allowed for grain yields of 11.7 and 13.2 kg ha-1, for the aeration and injection treatments, whereas surface application produced only 9.7 kg ha-1.