In some years, tent caterpillars seem to be everywhere; in others, they drop out of sight. Long-haired, wrinkly, and up to 3 inches long, these pests build gauzy nests in the forks of tree branches. Eastern types are black with a white stripe along the back and blue dots on the sides; western species bear various markings, but all have white dashes. During the day tent caterpillars dine outside their nest- unlike fall web-worms which expand their webs as they feed.