Response of Eastern White Pine to Nitrogen Fertilization

Abstract

Abstract Plots were established in nine eastern white pine stands; six on outwash soils and three on till soils. Nitrogen was applied to the plots at rates of 0, 50, 100, and 200 lb/ac. Four-year growth response functions for basal area/ac and merchantable cubic ft volume/ac were developed. Basal area growth was 9.2 ft²/ac greater and volume growth was 235 ft³/ac greater on the till soils compared with the outwash soils, regardless of application rate Both basal area and volume growth increased as basal area/ac increased. Maximum basal area response, 5.7 ft²/ac, and maximum volume response, 198 ft³/ac, was estimated to occur at an application rate of approximately 160 lb of nitrogen/ac, with incremental response being greater at lower application rates. Fertilization at a rate of approximately 100 lb of nitrogen/ac appears to be a cost effective practice for many white pine stands. North. J. Appl. For. 8(2):83-85.