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Abstract
An outbreak of the balsam woolly aphid (
Chermes piceae Ratz.) is damaging and killing Pacific silver fir, subalpine fir, and grand fir extensively in western Washington and Oregon. It is most serious in southern Washington where an outbreak on Pacific silver fir was discovered in 1954. Since effective methods for controlling this insect under forest conditions have not yet been developed, all that can now be done to minimize its destruction is to salvage the dead and dying trees. Because of rapid deterioration of dead timber, early detection of infestation is essential to enable logging of affected stands before values are lost.
Citation
Buckhorn, W.J.; Lauterbach, Paul G. 1957. Timing of aerial surveys for the balsam woolly aphid. PNW Old Series Research Notes No. 142, p. 1-2