Eastern Tent Caterpillar

The life cycle of the eastern tent caterpillar consists of egg, larva, pupa and adult stages. In June or July, the female adult, a reddish-brown moth, lays numerous eggs (up to 300) on a branch. The eggs are held together by a sticky substance, and the following spring when the leaves begin to unfold, the eggs hatch into the larval stage. It is the larval stage (caterpillar) of the life cycle which causes damage. In approximately five to seven weeks, the caterpillars reach maturity. In early July, the caterpillar spins a cocoon and pupates for two weeks. After emerging as an adult, it mates and lays eggs within a period of 24 hours. Only one generation of Eastern tent caterpillars is produced each year.

To control this caterpillar, during the fall and winter months, cut off and destroy all egg masses that are found on the twigs. If you are spraying, early control is important. However, it is difficult because larvae begin feeding on leaves unfolding from the bud before there is adequate leaf surface to be sprayed. Insecticides with residual effectiveness are desirable. Most will kill larvae hit by the spray; however, larvae in webs are protected from sprays. Treat foliage and twigs during the day as the caterpillars hide in the webs at night. If treating fruit bearing trees, use an insecticide labeled for use on fruit trees.

Their favorite foliage is cherry and apple, however, if hungry enough they will attack grapes, Paw Paws and blueberries.*

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