Very Hungry Caterpillars

I was pruning some low hanging walnut limbs today when I found one branch covered with small (less than 1 inch) reddish caterpillars. The caterpillars had defoliated the leaves at the end of the branch.



These are the caterpillar stage of the Datana integerrima moth, also known as the Walnut Caterpillar Moth. As the name implies, walnut caterpillars favor walnut trees, but they will also feed on hickory and pecan trees and will occasionally infest apple, birch, honeylocust, oak, and willow.



These caterpillars have the interesting habit of rearing their front and tail ends in unison to ward off offenders.