By October and early-November, these eggs hatch into the overwintering fundatrices which move to the bases of next year's buds. In the past, people were encouraged to avoid growing Colorado spruce next to Douglas-fir because of the adelgids' life cycle. We now know that the adelgid can complete its life cycle on either host and winged forms can migrate several miles in search of their alternate host. A well timed spray schedule is the best control technique or attempt to find trees which demonstrate resistance. Some Colorado spruce varieties and provenances are apparently less prone to attack by this adelgid.
More work is needed to identify good resistant stock.
These should be selected for landscape use. This kills the adelgids still trapped within the gall. This technique is only useful where the trees have a few galls. This technique will not prohibit the formation of galls in the next season. Dormant Oil Sprays - Dormant oil sprays have been used to control this pest.