Species
Adelges cooleyi (Douglas fir adelgid)
The gall adelgid (Adelges cooleyi) is an adelgid species that produces galls in spruce trees. They infect the new buds of native spruce trees in the[foothills of the Rocky Mountains in the spring. They also attack blue spruce to a lesser degree. The insects complete two generations within the year. They require two different trees for its life cycle, the second being the Rocky Mountain Douglas-fir. They may also attack Sitka, Engelmann, or white spruce. The…