Eastern tent caterpillar

Tent caterpillars are among the most social of larvae. The adult moth lays her eggs in a single batch in late spring or early summer. An egg mass contains about 200-300 eggs. Within three weeks, fully formed caterpillars can be found within the eggs. They lie quiescent until the following spring, when they chew their way out of the eggs just as the buds of the host tree begin to develop.