There is unfortunately not a lot of information on the reproductive, and life cycle of Hyphantria cunea. However, since they are in Order Lepidoptera and undergo complete metamorphosis from larvae to pupae, to adult we can fill in the blanks with basic knowledge on the life cycle of typical Lepidoptera. A female Hyphantria cunea will lay her eggs after mating with a male. She will deposit her eggs up in a tree, typically on a branch surrounded by leaves or on leaves. The larvae will hatch during the early to late fall and once they hatch they immediately begin feeding on the leaves of the tree. The larvae create a web-like tent (hence why they are called fall webworms) that helps protect them from diurnal predators such as bird and wasps.

Hyphantria Cunea Larva

The larvae will continue consuming leaves to store up energy for metamorphosis. Because metamorphosis is such a complicated process on the biochemical level, a lot of energy is needed to undergo this process. So the webworms need to eat a lot! Once they have reached a certain size, the webworms will start to transform into their pupae stage. The pupas are made out of the same material as their “web-tents” but are rolled more tightly together to provide a protective barrier from external extremities. While inside the cocoon, the larva undergoes the complicated process of changing from a larva into an adult moth form. Once the metamorphosis is complete, the moth will emerge from the cocoon and take flight. The adult will spend most of its time pollinating and feeding from flowers. During mid to late summer, the moths will mate with one another. Female moths attract the males by using a special kind of pheromone. Once the copulation is completed, the male will leave the female. The female will then deposit her eggs on a leaf or tree, and the cycle starts all over again.