forest tent caterpillar moth malacosoma disstria

The forest tent caterpillar moth (Malacosoma disstria) is found in most of the continental United States and Canada south of 61°N latitude.
It's more common east of the Mississippi River.

The Forest Tent caterpillar moth has a one-year life cycle.
After overwintering as a fully developed embryo within the eggshell, the larvae hatch in the spring when the leaves expand and feed them.
As they grow, larvae stay together in colonies and start building a silken mat on the branch and trunk of host trees.

Five or six weeks after hatching, the caterpillars spin yellow cocoons of silk colored in a folded leaf, bark crevice, or other sheltered place. In these cocoons, the larvae molt into pupae. Buff-brown moths emerge about 10 days later and live for only a few days during which they mate and females lay eggs.

Tent caterpillars are more of a nuisance than detrimental to overall tree health and vigor. Depending on the size of the tree and the intensity of the tent caterpillar infestation, an infested tree may not "flush out" like an uninfested tree.
A infested tree may take on a "ragged leaf" appearance.

In temperate regions Outbreaks are common on a variety of hardwoods, especially sugar maple and red oak.
In Boreal regions Outbreaks occur on trembling aspen.
In the Western United States Aspen is the preferred host, but alder, basswood, birch, cherry, cottonwood, elm, oak, poplar, various fruit trees, and willow.