Cooley Spruce Gall Adelgid in Northern Arizona above 6000’ Elevations
Cooley spruce gall adelgid is a common aphid-like insect that feeds on ornamental spruce and Douglas-fir trees in northern Arizona. The gall adelgid causes unsightly galls to form on the tips of the branches of spruce trees. A snowy and yellowing appearance occurs on Douglas-fir. Engelmann, Colorado blue and white spruces are the hosts for the insects’ primary gall forming actions. Douglas fir is the secondary host. Removal of the galls as soon as they appear will reduce populations in subsequent years.
Reviewed; 10/2014. Originally Published: 2002AZ1247-2014
- douglas fir
- integrated pest management