Bitterroot Restoration

Class: Insecta
Order: Lepidoptera
Superfamily: Lasiocampoidea
Family: Lasiocampidae
Subfamily: Lasiocampinae

The Eastern tent caterpillar (Malacosoma americanum) is a univoltine, social species that forms communal nest in the branches of trees. It is sometimes confused with the gypsy moth, or the fall webworm and may be erroneously referred to as a bagworm which is the common name applied to unrelated caterpillars in the family Psychidae.

The caterpillars are hairy with areas of blue, white, black and orange. The blue and white colors are structural colors created by the selective filtering of light by microtubules that arise on the cuticle. The adult moth lays her eggs in a single batch in late spring or early summer. The egg masses contain on average 200-300 eggs.

Control:
Control is not normally necessary. Defoliated trees usually refoliate after being attacked. Chemicals can be used to protect fruit trees, or tents containing the caterpillars may be picked off and destroyed.