Adelges cooleyi (Hemiptera: Adelgidae)
Cooley Spruce Gall Adelgid
Deming, Whatcom County, Washington
September 10, 2012

Adelgid nymphs on a Douglas fir needle, their food source for one generation. Some of this generation will develop wings and fly to a spruce, where they will overwinter in preparation for laying eggs in the spring. The generation that lives on the spruce will cause galls, but no galls are induced by the adelgids on Douglas firs.