Cost of pruning Douglas-fir in coastal British Columbia

Artificial pruning can increase the quantity of high-value clear lumber harvested from Douglas-fir, but the pruning cost per tree is relatively high. To prune a young Douglas-fir to 6 metres in one lift and two lifts took, respectively, 9.5 and 10.1 minutes in 14- and 18-year old stands with average spacing between trees of about 3 metres on flat or 0-30% south-facing slopes in coastal British Columbia. The associated costs were $2.09 and $2.22. This included minor travel time between trees, but excluded the cost of travelling to the site, selecting and marking trees to be pruned, and purchasing and maintaining the pruning equipment. Differences in pruning time between one-lift pruning and two-lift pruning, in one or two passes, were small. A D-handled saw was preferred to the more strenuous snap-cut pruner with ratchet-style pinions, based on observations on a pruning time-study of 5 operators. Key words: pruning saw, snap-cut pruner, pruning time, one-lift pruning, two-lift pruning