Alder (Alnus)-Fall webworm

Hyphantria cunea

Pest description and damage Large silken tents filled with caterpillars, frass and dead leaves, that eventually engulf entire branches of deciduous trees. Young caterpillars are pale greenish or yellow with a dark stripe down the back and a yellow stripe along the sides. Long silky hairs arise from yellow and black tubercles. When mature, the caterpillars are covered with yellow or rusty- to black-colored silky hairs. Adults are bright white with orange and black markings on the underside of the abdomen. Woolly moth scales cover and protect masses of 200 to 500 greenish eggs. Larvae can defoliate young trees.

For biology, life history, monitoring, and management


Management-chemical control

See Table 2 in: