Severely repressed lodgepole pine responds to thinning and fertilization:19-year results

Abstract

A set of speculative and exploratory treatments was applied to a severely repressed strand of 18-year-old lodgepole pine in 1979. After 19 years, various combinations of row thinning, hand thinning and fertilization have provided a remarkable range of results, with the best treatments gaining 3 m in top height and 8 m in apparent site index (reference age 50 years breast height) over the untreated stand. The best results were observed where both growing space and nutrition were improved. Extrapolation of the results using simulation suggests large gains in yield at harvest. Key words: thinning, fertilization, lodgepole pine, repression, stagnation