Its larvae spin large webs in the trees, which may enclose entire branches.

During most years, a fall webworm infestation can be ignored, especially if it is in a large, mature tree in good condition. When small trees are attacked, they can be severely defoliated and can even be completely encased by webs. In most cases, complete defoliation will not kill the treefelling.bar: Steve Upson. Hyphantria cunea Drury (Lepidoptera: Arctiidae) The fall webworm is native to North America and is found throughout the United States, Canada and Mexico.

It inflicts the most damage on shade trees, but can cause problems in apple and pear orchards.

Its larvae spin large webs in the trees, which may enclose entire branches. Sep 01, Fall webworms eat the leaves of many species of deciduous trees and bushes. This damage occurs late in the summer shortly before the trees normally drop their leaves for fall.

Therefore, fall webworms very rarely do serious damage to trees. In most cases the trees will grow their leaves back the following treefelling.bar: Elizabeth Barnes. Sep 25, Fall webworms are normally found in deciduous trees; they're eating leaves that were just about to fall off the tree for autumn.

So while their nests may be a bit unsightly, the only damage these caterpillars cause is aesthetic.