Hello, I’m Amanda McNulty with Clemson Extension and Making It Grow. The webworms we’re seeing in record numbers this year started as eggs laid by a female moth on the ends of branches, rather than in crotches of trees where the eastern tent caterpillar moth lays her eggs. When they hatch, they immediately start making their web as a safe way to feed and they expand the nest making large messes. After about six weeks they drop to the ground, find a sheltered place, and spin their cocoons. They remain there until next spring when they emerge, mate, and the females start laying clutches of eggs. They aren’t harmful to trees, just really ugly and unsightly, the exception being possibly young apple or peach trees where growers can control them with weekly sprays of a specific type of bacillus thuringiensis.
The lifecycle of webworms
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