This insect is related to aphids. Not much is known about this reclusive insect. Unlike most insects the cooley spruce gall adelgid has a very complex life cycle. This insect pupates through six different forms during its life. Of these six forms only the first is responsible for the formation of galls on Colorado and White spruce. The five remaining forms feed on the needles of the host tree. When reproducing the cooley spruce gall adelgid will form protective covers which are similar to cotton balls to cover their eggs. These white specks are present early in the spring and have been known to continue throughout the summer.
Cone-shaped galls will begin to appear early in May as the tree produces new growth. These galls begin as a green colour but turn to a deep red later. As the gall dries out it will turn to more of a brown colour. These dried out galls can be found on the branches several years after they are dead. If enough of these pests are present, they can cause a newly planted or young spruce to become stunted and deformed in growth. The newly formed buds dying on a branch, which is affected by the galls, cause this.
CONTROLLING THE PROBLEM:
Handpicking and then burning the galls as they appear is one way of gaining some control over this pest. If you are using an insecticide please be sure to follow all the directions on the label before and while applying. Your best bet when using one of these chemicals is to apply them early in the spring as the buds on your new growth is appearing.