Insect Management Handbook

Halisidota argentata

Pest description and crop damage Adult moths are brownish or tan with distinct silver-white spots on the wings. The caterpillars can reach 1.5 inches in length and are mostly reddish-brown with some blue-black or yellowish hairs.

Synanthedon sequoiae

Pest description and crop damage The adult moth is clear-winged with yellow and black markings resembling yellow-jacket wasps. The larvae are about 1 inch long, yellowish, with a reddish brown head.

Cylindrocopturus furnissi

Pest description and crop damage The Douglas-fir twig weevil is a small, wingless, grayish-black beetle with white markings and sometimes pinkish spots. The larvae mine under the bark or inside twigs. Infested twigs and small branches often turn a reddish-brown and die back. Small, stressed trees are especially susceptible to attack by the weevils, particularly in dry years.

Orgyia pseudotsugata

Contarinia spp.

Adelges cooleyi

Pest description and crop damage This aphid-like insect feeds on newly growing needles. Adelgids appear as woolly or cottony tufts on the undersides of needles, with heavily infested trees appearing "frosted" or flocked. Small purplish insects are found underneath the cottony tufts.

Dioryctria spp.

Cinara spp.

See:

Common Pests of Nursery Crops

Lepidosaphes ulmi

See:

Birch (Betula)-Oystershell scale

Common Pests of Nursery Crops

Coccus hesperidum

See:

Common Pests of Nursery Crops

Pest description and crop damage Flat and brown. Small, about 0.19 inch long. Sooty mold indicates presence in abundance.