Q: How do I get rid of webworms in trees?
A: Why worry? Webworms do not cause long-term, permanent problems for an otherwise healthy tree. What they are feeding on is a temporary part of the plant – the leaves. Each leaf is essentially an annual – emerging in spring, growing through summer and falling in fall or winter. They are not feeding on or damaging a permanent part of the plant.
Webworms feed on trees in nature. In these natural areas no one is worrying with the trees. If you were to tag or label some of the trees infested with webworms in these natural areas and go back the following spring, you’d find trees that look perfect with no hint of damage.
We, as humans, do more damage in our efforts to control webworms than the worms would ever be able to do. Some people prune out the branch or limb on which these caterpillars are feeding. In doing this, they are removing permanent parts of the plant. Left alone, these branches and limbs would still be on the tree and would eventually produce new leaves. Some people burn the worms, possibly causing permanent damage to the limbs.
One option is to let these caterpillars run their course. If you do decide to spray, keep in mind that the webs these caterpillars form are difficult to penetrate with water or sprays. Also, be very careful when spraying overhead. Insecticides that contain acephate, bifenthrin, carbaryl, cyfluthrin, lamdacyhoalothrin or permethrin can be used. Always follow label directions and precautions for the product you use.