Effects of Applying Five Nitrogen Rates on Quality of Nine Varieties of Introduced Perennial Forages

A single-location, three-year study (2008-2010) was conducted near Ardmore, OK, to determine the effects of five nitrogen rates (0, 50, 100, 200, and 300 lb N/acre) on crude protein (CP) and total digestible nutrient (TDN) concentrations of seven varieties of bermudagrass and two varieties of old world bluestem. Four seeded and three vegetatively propagated (hybrid) bermudagrass varieties were tested. Both CP and TDN concentrations were affected by N rate, variety, and year. Applying N increased CP and TDN concentrations in all varieties tested. All bermudagrass varieties had higher CP and TDN concentrations than either old world bluestem variety at all N rates tested. Seeded bermudagrass varieties had higher CP and TDN concentrations than hybrid bermudagrass varieties when fertilized with 200 or 300 lb N/acre, but not when fertilized at 0, 50, or 100 lb N/acre.