Lumber Recovery from Beetle-Killed Spruce Trees, Kenai Peninsula, Alaska

A four-level, visual classification system based on tree condition was developed for the beetle-killed spruce on Alaska's Kenai Peninsula. The lumber recovery study estimated lumber volume and value recovery for each of the deterioration classes. Trees were selected by dbh and deterioration class from a wide geographic range on the Kenai Peninsula. Defect present prior to attack by beetles (existing defect) played a significant role in recovery results. Both volume and value of logs from live and dead trees decreased significantly. Volume and value recovery did not statistically differ among deterioration classes 2, 3, and 4. Models were developed for each deterioration class that incorporate losses from existing defect. Each 1% of existing defect translates to a decrease of 0.3% in cubic recovery and a loss of $1.92 per hundred cubic feet (CCF) of gross log volume. The recommendation is to have two deterioration classes: one for live and infested trees and a second for dead trees. Information on individual deterioration classes is also provided. West. J. Appl. For. 13(2):54-59.