Hello Gardeners, I’m Amanda McNulty with Clemson Extension and Making It Grow. The fall webworms are spectacularly visible these days. In spring, adults emerge from overwinter cocoons, females lay eggs and the first generation of this native caterpillar begins feeding in early summer. They don’t cause much damage as by the time their populations build up towards the end of summer, the deciduous leaves they’re feeding on are ending their life cycle. People get upset about the ugly, large masses of webs filled with frass (the nice word for insect excrement), but the best reaction is just avert your eyes. And usually the nests are usually way out of reach -if you try to spray them with insecticide you’ll get more of it on yourself then on the protected caterpillars. Never try to burn these nests, the leaves are getting dry and you might catch the whole tree on fire.
Life Cycle of Fall Webworms

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