Submitted to: Crop Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/29/2004
Publication Date: 3/1/2005
Citation: Springer, T.L., Taliaferro, C.M., Hattey, J.A. 2005. Nitrogen source and rate effects on the production of buffalograss forage grown with irrigation. Crop Science. 45:668-672. Interpretive Summary: High dry matter yields of buffalograss [Buchloë dactyloides (Nutt.) Engelm.] are possible under intensive management of nitrogen fertilization and irrigation. An experiment was conducted to determine the effect of solid cattle manure, liquid swine effluent, or commercial fertilizer (urea) at three application rates (0, 120, and 240 kilograms N hectare) on the growth and yield of buffalograss under irrigation. In this experiment, dry matter yields during the establishment period exceeded 11,000 kilograms per hectare and stabilized near 7,500 kilograms per hectare in later years. The source of nitrogen had little affect on the dry matter yield. Forage dry matter yield increased nearly linearly with rate of applied nitrogen each year. Age of stand had a significant influence on both the crude protein concentration and digestibility. After the establishment period, crude protein concentration stabilized to just above 60 grams per kilogram and digestibility to just above 350 grams per kilogram. Fertilization with animal manures did not effect digestibility. Further research is needed to determine optimum irrigation schedules and amounts as well as frequencies of harvest. Optimizing irrigation or harvest frequency might increase crude protein concentrations and digestibility without significantly lowering dry matter yield. Nitrogen, phosphorus, or potassium levels did not significantly change in the soil over the study period, however, further research is needed to determine the long term effects of fertilization with animal manure on possible accumulation of elements in the soils.
Technical Abstract: Application of livestock manure to crop lands is one of the most obvious methods of recycling nutrients. An experiment was conducted to determine the effect of solid cattle manure, liquid swine effluent, and commercial fertilizer (urea) at three application rates (0, 120, and 240 kilograms N hectare) on the growth and yield of buffalograss [Buchloë dactyloides (Nutt.) Engelm.] under irrigation. Two forage harvests were taken during the growing season and forage height was measured before each harvest. Significant differences (P < 0.05) in average forage height were found for rate of applied nitrogen, source of nitrogen, age of stand, and an stand age by rate interaction. Significant differences (P < 0.05) in seasonal total forage dry matter production were found for rate of applied nitrogen, age of stand, and a stand age by rate interaction. Age of stand influenced both the crude protein concentration and IVOMD. Given the availability of livestock manure in the Great Plains region and the need for disposal of this by-product from confined animal feeding operations, the application of manure to buffalograss for hay production could be an economically viable and sustainable production system. Further research is needed, however, on the long term effects of applying animal manure to soils in relation to nutrient loading and water quality.