The Douglas-fir beetle outbreak on the Shoshone National Forest is evaluated for the eighth consecutive year. Adult emergence in 1996 showed a single peak. Overwintering brood in 1996 were used to predict population levels for 1997. Brood levels declined from 1995 but 81% of the overwintering brood are adults. Damage levels (number of trees killed) was at its lowest point in the last 7 years, a 4.5 fold decline from 1995. Brood counts indicate a steady or slight increase in beetle populations; however, in most areas suitable host trees are becoming scarce.
Management alternatives include salvage and sanitation, tree baiting, silvicultural treatments, and no action. Recommended actions vary depending on individual areas.
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