Eastern Tent Caterpillar

When the forsythia flower, it’s time to start watching for the Eastern tent caterpillar.

This insect is more of a nuisance than threat to healthy trees. The tiny caterpillars emerge in early spring and begin feeding and creating webby tents when temperatures warm and tree leaves expand. A family of caterpillars lives in each webby tent. They leave the tent to forage for food early in the morning, evening or at night.

Use your hand or a stick to knock the tent out of the tree when the caterpillars are present. You can apply organic Bacillus thuringiensis kurstaki to control the young larvae. Spray the tent and the leaves several feet beyond.

In winter, check crabapples, plums, cherries and other susceptible plants for the egg masses that resemble a small shiny glob of mud. Prune off infested branches and destroy egg masses as found.

A bit more information: Once the eastern tent caterpillars reach full size they drop to the ground and seek a safe place to pupate. The adults emerge in early summer, laying eggs for next year’s offspring.