Harvesting mountain pine beetle–killed pine while protecting the secondary structure: trials to support a partial harvesting strategy for addressing the mid-term timber supply
In this FPInnovations–Feric Division project, we studied a series of partial harvesting trials in which the objective was to harvest all the pine trees while protecting the secondary structure in stands infested by the mountain pine beetle. The purpose of this type of treatment is to salvage the present value of the beetle-killed pine while preserving the existing secondary structure to provide a viable stand by the mid-term timber supply period (15 to 50 years from now). In this report, we provide the results from four trials in the Prince George (B.C.) Forest District using four different ground-based partial harvesting methods: a motor-manual (chainsaw) cut-to-length (CTL) method, a mechanized CTL method, a motor-manual full-tree method, and a mechanized full-tree method. Variations in pre-harvest stand attributes, harvesting equipment, and methodology resulted in differences in the total trail area, harvesting costs, and amount of secondary structure remaining undamaged in the residual stands. The results indicate that with an appropriate harvesting method and sufficient secondary structure present in the pre-harvest stand, it should be possible to harvest the mature pine trees and provide stands that will produce acceptable volumes of timber in the mid-term time period.