Eastern Tent Caterpillar

Encyclopedia Article

Description of eastern tent caterpillars

Dark colored caterpillars with lighter stripes down their sides.  They form silvery-gray webs, usually located at the fork of a major branch on a tree or shrub.

Eastern tent caterpillar larvae and tent. Photo by Tammy Curley.
Eastern tent caterpillar larvae and tent.
Photo by Tammy Curley.

Life cycle of eastern tent caterpillars

Caterpillars emerge in late April and early May from eggs that were laid on small twigs last summer by the female moths. During the daytime the caterpillars feed on buds and foliage. On cloudy rainy days and at night the caterpillars remain in the protective confines of the tent. Tents start out very small but enlarge as the caterpillars feed and grow and add to the tents, making them more obvious in the landscape and along roadsides.

Damage caused by eastern tent caterpillars

Caterpillars feed on buds and foliage of apple, crabapple, wild plum, cherry and similar trees.

Management of eastern tent caterpillars

Damage can be reduced by removing and destroying tents and caterpillars as soon as they are noticed. Tent removal should be done in early morning or late evening or on cool rainy days when the caterpillars are occupying the tents. The caterpillars and the silk webbing are harmless to people; no harm comes from taking down the tent with your bare hands, although I understand some people would rather do this operation with a pole or gloved hands

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