Tent Caterpillar

*Malacosoma spp.*

Content coming soon for this insect guide.

Insect Profile

Beneficial Rating

-4 Pest

Active Months

JanFebMarAprMayJunJulAugSepOctNovDec

US Distribution

NortheastSoutheastMidwestSouthwestWestPacific Northwest

Habitat Preferences

Gardensorchardsforests

Taxonomic Group

Caterpillar

Order

Lepidoptera

Family

Lasiocampidae

Lifecycle

Tent caterpillars overwinter as eggs laid in hardened, dark-colored masses that encircle twigs and small branches of host trees. The larvae hatch in the early spring, typically around March, coinciding with the opening of tree buds. These social caterpillars construct a communal silken tent in the crotch of a tree, which they use for shelter. They emerge from the tent to feed on leaves, growing through five to six larval instars over a period of four to six weeks, eventually reaching a length of 2 to 2.5 inches. Once fully grown, the caterpillars leave the nest to find a protected location to spin a cocoon. The adult moth emerges approximately three weeks later. After mating, the female moth lays her eggs, and the cycle begins anew. There is one generation per year.

Overwintering Strategy

Overwinters as eggs in hardened, dark-colored masses wrapped around twigs and small branches.

Native Range

North America

Attracted By

Wild cherryapplecrabappleplumpeachpearhawthorn

Repelled By

Sagedilloreganorosemary

Organic Control Methods

Organic control of tent caterpillars primarily involves manual removal and biological methods. During the winter, egg masses can be located and pruned out of trees to prevent them from hatching. In the early spring, small tents can be removed by hand and destroyed. For larger infestations, a targeted application of *Bacillus thuringiensis* var. *kurstaki* (Bt), a bacterium that is toxic to caterpillars, can be effective, especially on young larvae. It is important to apply Bt directly to the foliage that the caterpillars will consume.

Companion Planting

Nasturtiums can be used as a trap crop to attract egg-laying moths away from more valuable plants. The affected nasturtium leaves can then be removed and destroyed. Interplanting strongly scented herbs and flowers, such as sage, dill, oregano, and rosemary, among crops can confuse and deter the moths from laying eggs nearby.