Tussock Moths

Ah, it’s that time of year again. Spring is in the air, new leaves are sprouting, and caterpillars are falling from the trees. Yes, it’s tussock moth season! Florida is home to three species of tussock moths, and the caterpillars are far more well-known than the moths themselves, due to their habit of appearing in prodigious numbers and dropping down on people from the oak trees above.

Tussock moth caterpillars are bothersome to many people, in part due to their sheer numbers. Tussock moth adults emerge in early spring, when oak trees are putting on new leaves. The adult females are flightless, so males seek them out to mate. Females then lay eggs on the remains of their own cocoons, and caterpillars hatch soon afterward. They feed for a few weeks, and then seek out sheltered locations to pupate to cocoon.

All of this happens within a few weeks in spring when new leaves are at their best, causing many to view it as a bit of an invasion, especially due to the fact that the caterpillars drop from the trees on thin strands of silk when they feel threatened. When ready to pupate, they look for sheltered areas close to the oak trees where they have been feeding. Houses surrounded by live oaks can be invaded by these caterpillars by the hundreds around this time.

Most tussock moth caterpillars (there are hundreds worldwide in the family Lymantriidae) have urticating hairs, which can cause allergic reactions in humans. Although Florida’s three main species are not as toxic as others, some individuals may be sensitive to skin contact with these caterpillars, so it’s best to avoid contact when possible. The urticating hairs are also incorporated into the cocoons, so avoid handling them as well.

This is a species many have come to view as a pest. If you need tips on controlling these caterpillars, click here to visit the University of Florida Entomology Dept website.