@article{franzluebbers_poore_freeman_rogers_2019, title={Soil-surface nutrient distributions in grazed pastures of North Carolina}, volume={74}, ISSN={["1941-3300"]}, DOI={10.2489/jswc.74.6.571}, abstractNote={Soil nutrient distribution in perennial pastures is likely affected by livestock activities, but detailed spatial patterns on a diversity of farms have not been widely investigated. Livestock management variables, such as placement of drinking water sources, fencing, and winter hay-feeding stations, as well as pasture utilization through seasonal stocking, could affect nutrient distribution despite attempts at uniform application of fertilizers. We sampled perennial pasture portions of three research station farms in North Carolina on a 40 m grid in 2016. Twenty-two soil variables were measured, including routine soil testing of pH, cation exchange capacity, and extractable phosphorus (P), potassium (K), calcium (Ca), and magnesium (Mg), as well as nonroutine testing of sand concentration, total and particulate organic carbon (C) and nitrogen (N), and soil-test biological activity. Large statistical variations in nearly all variables occurred within a location. Severely deficient and heavily excessive levels of soil-test P and K were observed on the same farm and sometimes on the same paddock. Soil-test biological activity and total soil N also varied spatially within locations. High nutrient concentrations and soil-test biological activity were congregated in zones of several pastures, which could be related to historical winter hay-feeding and permanent drinking water locations. At the Piedmont location with recent winter hay feeding, both organic and inorganic indicators generally corresponded to the same enrichment zones. At the Coastal Plain location with abandonment of some historical feeding locations, soil-test P remained high near feeding stations, but soil-test K and total soil N became more uniformly distributed due to leaching and/or decomposition dynamics over time. We suggest that both organic and inorganic soil testing indicators should be measured to make nutrient recommendations for better resource utilization. Livestock managers are encouraged to sample pastures in expected zones of nutrient differentiation so that nutrients can be used efficiently and environmental threats can be mitigated.}, number={6}, journal={JOURNAL OF SOIL AND WATER CONSERVATION}, author={Franzluebbers, A. J. and Poore, M. H. and Freeman, S. R. and Rogers, J. R.}, year={2019}, pages={571–583} }
 @article{rogers_harvey_poore_mueller_barker_1996, title={Application of nitrogen from swine lagoon effluent to Bermudagrass pastures: Seasonal changes in forage nitrogenous constituents and effects of energy and escape protein supplementation on beef cattle performance}, volume={74}, DOI={10.2527/1996.7451126x}, abstractNote={A 2-yr study was conducted to evaluate 1) the effects of nitrogen level from swine lagoon effluent on forage composition and animal performance and 2) the effects of supplemental escape protein (EP) on performance by steers grazing pastures fertilized with swine lagoon effluent. Bermudagrass (Cynodon dactylon) pastures were fertilized via sprinkler irrigation with either 448 or 896 kg/ha of N from swine lagoon effluent (two pasture replications/treatment). Within each pasture, four supplement treatments were evaluated using electronic Calan gates (8 steers.pasture-1.yr-1). The treatments were 1) negative control (pasture only); 2) energy control, which supplied 79.9 g of EP.hd-1.d-1; 3) 159 g of EP.hd-1.d-1, and 4) 239 g of EP.hd-1.d-1. Gains were increased (P < .05) an average of .15 kg/d by supplementation, with no differences in gain among supplements. Forage samples representative of that grazed by steers (CONSUM) and representative of all available forage (AVAIL) were obtained at 14-d intervals. Total CP content of CONSUM and AVAIL samples were slightly higher (P < .20 and P < .15, respectively) from pastures fertilized with 896 compared with 448 kg/ha of N (20.8 vs 20.0% for CONSUM and 15.2 vs 14.2% for AVAIL). Concentrations of nonprotein N and soluble true protein (% of CP) in both AVAIL and CONSUM samples were higher (P < .06) from pastures fertilized with the higher N level. Total N uptake by the plant, based on CP content and animal grazing days/ha, was essentially the same for both N treatments.}, number={5}, journal={Journal of Animal Science}, author={Rogers, J. R. and Harvey, R. W. and Poore, M. H. and Mueller, J. P. and Barker, J. C.}, year={1996}, pages={1126} }