Predicting Yield Response to Nitrogen Fertilization on Northern Great Plains Rangelands

Abstract

Using a data base developed from range fertilization research results in the Northern Great Plains, yield-predicting equations for both fertilized and nonfertilized range (r2=0.83; n = 194 and r2=0.88; n = 51, respectively) were developed. Independent variables included combinations of monthly precipitation and average site yield for nonfertilized range and additional variables representing N-rate, N-sink effect, and N-rate with precipitation interactions for the fertilized range. Average site yield provided an effective means of accounting for the wide range of inherent productivity among range sites. The results of this research indicated that, in the Northern Great Plains, yield response of native range to N fertilization can be reliably predicted using readily obtainable climatic and site data.