Caterpillar Webbing on Texas Mountain Laurel Now

Now is the time you may be seeing some webbing in your Texas mountain laurel tree or shrub. This happens nearly every year but is relatively easy to control.

There is a moth, called the Genista moth, that lays its eggs on the stems of Mountain Laurel. When these eggs hatch into small caterpillars or larva of the moth, they feed on the leaves of this plant. Prior to doing that, they form some webbing around their kitchen area. 

Texas mountain laurel

They normally do not cause a lot of damage but in some cases their numbers can be so high that the visual damage can be alarming. This is a little strange because the leaves of Texas mountain laurel are considered to be somewhat toxic. Most animals do not want to eat those leaves. But this caterpillar has evolved with this plant and can tolerate these toxins. These toxins reside in the caterpillar and sold the caterpillar in itself is not a favored food of predators. Plus the silken webbing deters other potential enemies.

If you have these plants in your landscape, you might check them for damage. If the damage is minor, just leave them alone. If it is severe, organic sprays of Dipel or Thuricide will normally control. You may have to destroy the webbing so that the spray can land on the leaves they are eating. This organic spray relies on the caterpillars eating sprayed foliage. The webbing may interfere with the spray landing on the leaves. 

You can also use Spinosad and it will do about the same thing. Several sprays of insecticidal soap will also probably work.