N, P, And K Fertilization of Tall Fescue (Festuca arundinacea Schreb.) Overseeded Range in Eastern Oklahoma

Abstract

A native hay meadow in northeastern Oklahoma was overseeded with tall fescue (Festuca arundinacea Schreb.) and fertilized for 6 years with N in August and February to encourage tall fescue growth in late fall and early spring, thus extending the green forage season. The effect of P and K fertilizer on forage yield and plant nutrient concentration was determined. Cool-season N fertilization (112 kg/ha) nearly doubled tall fescue yield and increased forage nitrogen concentration without altering warm-season grass production. Additions of P (15, 29 kg/ha) and K (28, 112 kg/ha) increased cool-season forage yield marginally and increased fertilizer N recovery but had no desirable effect on forage N, P, and K content. Tall grass decreaser species were dominant at the end of the study. Available soil P increased with P fertilization and available soil K increased with K fertilization.