Q: We have noticed lots of caterpillars nesting in the sweetgum trees. Is it worth trying to control this infestation with insecticides or will they disappear by themselves?

A: I think you’re seeing fall webworms. They build their protective webs in pecan, sweetgum and small maple trees. Their home-building activities started in June but the webs are just now becoming noticeable. Although they do not permanently harm trees, they are certainly unsightly. One simple control method is to pull the webs down with a long pole. Wasps, yellowjackets and hornets love to eat caterpillars and have been so far kept at bay by the diaphanous dwelling cover. You could also spray around and into the nest with organic caterpillar killers that contain Bacillus thuringiensis (B.t.)