Thinning lodgepole pine in southeastern British Columbia (EP 384 and 385)

Objectives

To determine the effects of different levels of post-thinning density on the growth and development of mid-rotation lodgepole pine.

Treatments

The study tests five levels of thinning (20, 40, 60, 80, and 100% of "normal" stocking) plus an unthinned control. Actual post-thinning densities range from ~ 750 st/ha (20% of normal stocking) to 2900 st/ha (100% of normal stocking). The mean density of the unthinned (control) treatment was ~ 4900 st/ha at the time of trial establishment. Each of the six treatments is replicated twice, for a total of 12 treatment plots. Treatment plots vary in size depending on thinning level, and range from 0.36 ha to 0.82 ha.

The study was established in 1952 in a 53-year-old lodgepole pine stand northeast of Canal Flats within the dry cool subzone of the Montane Spruce biogeoclimatic zone. The installation was re-measured on about a 5-year cycle until 1998, when it was switched to a 10-year re-measurement interval.

Publications

  • Johnstone, W.D. 1997. The effect of commercial thinning on the growth and yield of lodgepole pine. In: Proc. Commercial Thinning Workshop, October 17–18, 1996, Whitecourt, Alta. FERIC Spec. Rep. SR-122, pp. 13–23.
  • Johnstone, W.D. 2002. Thinning lodgepole pine in southeastern British Columbia: 46-year results. B.C. Min. For., Res. Br., Victoria, B.C. Work. Pap. 63.