Giant conifer aphids (Cinara spp.)
Cinara pseudotsugae
Pest description, and damage These aphids infesting Douglas-fir are up to 0.2 inch in length. They range in color from gray to brownish to black. Aphids establish large colonies on the twigs, but rarely are found feeding on needles. Feeding produces a honeydew that promotes sooty mold on foliage and underlying surfaces. Yellowjackets and ants are found in tree canopy foraging for honeydew.
For biology, life history, monitoring and management
See "Aphid" in:
Management-chemical control
See Table 1 in: