Year Established: 2011 Start Date: 2011-03-01 End Date: 2012-02-28
Total Federal Funds: $25,000 Total Non-Federal Funds: $50,001
Principal Investigators: Russell Muntifering, Yucheng Feng, Thomas McCaskey, Frank Owsley, Charles Wood
Abstract: This research will quantify effects of N fertilization regime on forage nutrient uptake, microbial and nutrient returns in grazing-cattle excreta and water quality of runoff from pastures with high background soil-test P. Permanent winter/spring (predominantly tall fescue) and summer (predominantly bermudagrass) pastures will be sod-seeded with triticale/crimson clover and cowpea, respectively, and receive no N fertilization, a single application of 50% of the recommended rate of N fertilization, or a split application of 100% of the recommended rate of N fertilization for the predominant seasonal forage. Statistical associations between runoff characteristics, precipitation patterns and amounts, microbial and nutrient returns from cattle feces, and forage productivity and uptake of nutrients for each plant speciec will be determined. Variance among these and their predictive relationships with nutrient, microbiological and sedimewnt loading in runoff will be established. We predict that the single-application treatment will be superior to the negative control and split-application treatments in terms of plant productivity and uptake of soil P, and that differences in nutrient uptake by pasture plants among experimental treatments will be mediated by changes in botanical composition of the pastures, plant productivity, and guantity and bioavailability of nutrients returned to the pasture in cattle feces.