Cankerworms , Alsophila pometaria and Paleacrita vernata. Cankerworms feed on chestnut . The measuring-worms or inchworms of these moths eat apple foliage during the spring. When the caterpillars are abundant, they may defoliate the trees. In early spring, caterpillars hatch from the eggs laid on the trees in late fall or early spring.
Older caterpillars are black or greenish with stripes.
Each species has only one generation a year. The abundance of cankerworms varies in cycles. The caterpillars can be controlled with one or more springtime applications of phosmet or azadirachtin, which are among the compounds registered for control of this pest in Connecticut. Consult the labels for dosage rates and safety precautions. Chestnut weevils, Curculio caryatrypes and C. sayi.