Initial thinning in red pine plantations.

Abstract

Response to thinning in six red pine plantations in Lower Michigan supported previous findings by showing basal area growth to vary little over a wide range of residual densities. Furthermore, the method of selecting trees for removal in the first thinning had little or no influence on basal area growth. However, the immediate effect of thinning on average stand diameter depends on thinning method and the proportion of the stand cut, and diameter growth after thinning depends on residual density. The residual densities tested range from 30 to over 200 square feet of basal area per acres. Thinning methods were (1) thinning from below, (2) thinning from above, (3) crown release (4) removal of alternate rows, (5) removal of every third row, and (6) thinning to increase growth on trees with the best potential for utility poles. It was concluded that initial thinning in plantations could reduce density to about 60 square feet of basal area per acre without reducing total yield and that these thinnings could be basically row thinnings.

Citation

Cooley, John H. 1969. Initial thinning in red pine plantations. Research Paper NC-35. St. Paul, MN: U.S. Dept. of Agriculture, Forest Service, North Central Forest Experiment Station