Swine Manure Application Timing: Results of Experiments in Southern Minnesota

Document
Description
Most producers in the upper Midwest apply manure in the fall because of the limited period for tillage, nutrient application, and planting in the spring. However, N from manure with a high composition of ammonium N is susceptible to losses under the same conditions that cause N losses from fall-applied inorganic fertilizers. Application of ammonium N at soil temperatures above 50 degrees F can lead to nitrification (conversion of ammonium N to nitrate) and subsequent loss of nitrate by leaching or denitrification. Previous research from the University of Minnesota Southern Research and Outreach Center (SROC) at Waseca showed that liquid dairy and hog manures injected in April produced yields 5% higher than manures injected in September and October. The study included seven site-years over a three year period in Southern Minnesota. (Randall, G.W., et al. 1999. J.Prod. Agric. 12:317-323). A 2006 Cornell University study (van Es, H.M., et al. 2006. J. Environ. Qual. 35:670-679) showed when applying dairy manure to corn, nitrate losses due to leaching were significantly greater when manure was applied in the early fall, especially in sandy soils. In contrast, early spring application showed the lowest nitrate losses during the three year study period for the two soils (loamy sand and clay loam). In order to determine the optimum time for swine manure application, the following experiments were carried out at SROC and on farm fields in southern Minnesota. Corn yield response and nitrate movement were measured over a range of fall swine manure application dates.
Date Issued
2012
Number of Pages
16
Decade
Rights Holder
Minnesota Water Research Digital Library
Rights Management
Public Domain