Spruce Budworm Damage in Aspen/Balsam Fir Stands Affected by Cutting Methods

Abstract

Abstract An aspen/balsam fir study area in Wisconsin with several replicated cutting treatments dating from 1950 when the stand was 36 years old became infested by the spruce budworm in 1976. Remeasurement in 1981 revealed that balsam fir mortality and growth loss were directly related to the amount of aspen removed from the overstory. Complete and commercial clearcutting of the overstory aspen produced 60% more balsam fir basal area than uncut plots by 1975. However, mortality from budworm defoliation averaged 98% of the basal area in these plots. Thinning from above best achieved the objective of early release and provided near maximum protection from the spruce budworm. North. J. Appl. For. 4:73-75, June 1987.