Ministry of Agriculture
Apple/Cherry Ermine Moth
Yponomeuta malinella (Zeller) / Yponomeuta
Mature apple ermine moth larvae on apple
Apple ermine moth adults and cocoons
Life Cycle: Both species of ermine moths overwinter as first-instar larvae under egg mass laid the previous summer. Larvae present late-April to mid-June; adults present July-August. Cherry ermine moth is present in southwestern B.C. and Vancouver Island. One generation per year.
Monitoring: Inspect leaves for larvae and/or feeding damage, or presence of white cocoons laid side-by-side near defoliated/webbed areas. Pheromone is available for monitoring male apple ermine moths.
Hosts: Apple ermine moth - apple, crabapple; Cherry ermine moth - cherry, plum, peach, hawthorn, mountain ash, serviceberry.
Comments: Larvae of both species are identical in appearance. Ermine moth nests can be confused with those of the fall webworm and tent caterpillars. Fall webworm nests are much larger and occur much later in the summer; tent caterpillars build silken pads on trunks and major limbs. Ermine moth nests consist of loosely gathered leaves that can extend the length of branches; however, the webbing is not as dense or thick as that of the fall webworm.
Body length: Adult - 10.0mm; Mature larva- 19.0mm