Fall Webworms

What They Are

Don’t let the name fool you, in Missouri City we can start to spot these insects in the summer months, most commonly in mulberry and pecan trees. Fall webworm (hyphantria cunea) is generally noticed because of its protective webs on sections of branches and leaves. Within these webs, the caterpillars feed off the fleshy part of the leaves, usually leaving a leaf skeleton behind. These hungry insects generally defoliate all the leaves within their web. If infestations get too large, the result can be tree decline or in rare occasions death.

How to Control Them

Fall webworms can have several generations in one growing season, so control is recommended sooner than later. Insecticides are available at many garden centers. If infestations are small, you can prune off the infested area of the tree and remove the insects before they can do additional damage to the host tree. Another option is to break the webs with a stick or rake. This allows the insects natural predators to feed on the caterpillars.

According to Texas Agrilife Extension, wasps, hornets, and birds will all feed on the webworms; be careful though, the caterpillar’s hairs may cause a rash if they contact your skin. Read more about webworms from Texas Agrilife Extension agent Nathan Riggs.