- Balsam Fir
The spruce budworm is the major insect pest of balsam fir. Budworm survives best on older trees and in dense stands. To minimize damage, manage fir on a 40- to 50-year rotation, keep large forest areas well diversified by age class, thin stands to maintain vigorous growth, and maintain a high spruce and hardwood component. Insecticide use may be warranted in high value stands that have been defoliated for two consecutive years and that cannot be harvested within five years.
Heart rot and root rot are major diseases. To mini- mize damage follow budworm management prac- tices to sustain vigorous stands and avoid scarring trees during intermediate cuttings.
Windthrow?\trees uprooted or broken by wind?\ can be a serious condition, especially on wet, shallow soils. Minimize windthrow by maintain- ing a well-stocked, vigorous stand. Do thinning and shelterwood cutting only on sites where fir is known to be windfirm. When making a partial cut, ensure the windward side is protected by a zone of uncut timber at least one chain wide and make cutting boundaries straight. In mixed stands with hardwoods, maintain a well-distributed hardwood component. If damage becomes severe, conduct a salvage harvest.