Eastern tent caterpillars moving into fruit crops
Editor’s note: This article is from the archives of the MSU Crop Advisory Team Alerts. Check the label of any pesticide referenced to ensure your use is included.
You may have noticed the cream colored “tents” of the eastern tent caterpillar, Malacasoma americanum, in trees along field edges and along roadways. These tents are made in the fall by this native insect in wild cherry, apple, and crabapple, and may also be found on hawthorn, maple, cherry, peach, pear and plum. Populations fluctuate from year to year, but this spring the dark caterpillars can commonly be seen emerging from their tents in large numbers, and caterpillars have been moving into nearby fruit crops.
Caterpillars of this species are distinguished by their blue and white and black markings along both sides and the orange-yellow tufty hairs along the body with a thin yellow stripe along the dorsal (top) surface. The caterpillars can move considerable distances from the tents once they reach later instars, feeding on perennial plants including many fruit crops. Although they feed on leaves during development, once the larvae are full grown (2 to 2.5 inches long), they stop feeding as they search for a place to pupate. Because of this, tent caterpillars rarely need specific management actions in crop fields and they are controlled by early season insecticide applications targeting other more important insect pests.
Dr. Isaacs's work is funded in part by MSU's AgBioResearch.