To thin or not to thin: Using the Forest Vegetation Simulator to evaluate thinning of aspen

摘要

Thinning experiments are costly to install and take decades of monitoring. Computer simulation tools, however, allow for the creation of "virtual" thinning experiments that forest managers can use as a guide in prescribing thinnings. The Forest Vegetation Simulator (FVS) was used to conduct a "virtual" thinning experiment to a range of residual densities (8, 10, 12, 15, and 20 ft spacings) at a range of thinning ages (5, 10, 25, and 40 yr) over a 50 yr time period. Stand level volume production was not enhanced through precommercial thinning, but average tree diameter was increased. Stand level volume was less after commercial thinnings but total volume production was increased if volumes removed during thinnings were considered. Tree diameter growth was greater when thinnings were performed at a younger age at and at a wider spacing. The greatest total volume production (removed during thinning and standing at age 50) was found to be nearly equal at 8 ft and 10 ft spacing with thinnings occurring at ages 10 or 25 on a site index of 80.