The Fall Webworm

The Fall Webworm

The Fall Webworm is a moth that produces webbed nests on a wide variety of hardwood trees during the late summer and fall seasons. The Fall Webworm is native to North America ranging from Canada to Mexico and feeds on just about any type of deciduous tree, where leaves are chewed and branches or the entire tree may become defoliated. It feeds on more than 200 different plants in the US, including 88 species of broadleaved trees. In NY, black cherry is the most frequently attacked host, but tents also occur on alder, apple, beech, birch and oak. Webworm Tents

Every year the Fall Webworm emerges with larvae appearing in late summer through early fall. The adult moth lays her eggs on the underside of leaves and hatch in about 1 week. The caterpillars are highly variable in coloration, ranging from pale yellow to dark grey with yellow spots and long and short bristles. Larvae feed inside the tents; this stage lasts about 4-6 weeks. The pupal stage overwinters in the bark and leaf litter at the base of the trees. The think brown cocoon is mainly made of silk. The adult is mostly white in our area. It may be marked by black or brown spots on the forewings.When populations of webworms are high, outbreaks usually do not last more than 2-3 years. The Webworm rarely kills trees.