The wig girdler beetle is Nature’s not-so-careful pruner. They are the cause of all the downed twigs and small branches we see on the ground in the fall. They’ve been working overtime this year.
The female twig girdler beetle lays her eggs just under the bark of a small branch, then chews around the branch so all that’s left is a small piece in the middle. The branch dies and the wind breaks it off and it falls to the ground. The fallen branch looks like someone cut it with a penknife. In fact, that’s what I thought when I saw the first ones at our place and wondered who was messing with our trees. The trees that I’ve seen infested most often are elm, pecan and persimmon, although the beetles attack others as well.
Eggs that have been deposited will hatch in about 3 weeks and the tiny larvae will feed on the dead branch and overwinter in it. In the spring, larvae will complete their development and become pupae. Adult beetles emerge in the fall and start the cycle over again. Adults belong to a group of insects called long-horned beetles because their antennae are at least as long as their bodies, which are a half to three-fourths of an inch.
To reduce damage to trees the following year, it’s best to get rid of the fallen branches. If you live in an area where burning is allowed, the easiest way to destroy them is to burn them, since larvae remain under the bark all winter.
Read more Nature Notes.
