Effects of Nitrogen and Phosphorus Fertilization on Yield and Protein Content of Oat Forage at Point MacKenzie

Abstract

One of the principal forages grown at Point MacKenzie dairy project about 40 miles southwest of Palmer in Southcentral Alaska is oats. Soils at Point MacKenzie are moderately to strongly acidic, ranging in pH from about 5.0-6.0, thus promoting the use of acid-tolerant plants such as oats. These soils have a moderately volcanic ash content whose weathered products have a high affinity for phosphorous (Ping and Michaelson, 1986; Michaelson and Ping, 1986). Soil depth varies from shallow to moderately deep and can be a critical factor during droughty periods. The research reported here is a continuance of previous work at Point MacKenzie that has provided information on yield and response of oats to fertilizer treatments (Mitchell, 1983; Michaelson et al., 1984). Two series of trials were conducted employing different nitrogen and phosphorous rates with one of the series also testing different times of harvest. This report is concerned with the effect of these treatments and crude protein content in Toral oats.