Tussock Moth Caterpillar (Egg Mass)

Found on tree trunks, branches, fences, and walls in forests, gardens, and urban environments.

Larvae (caterpillars) feed on a wide variety of deciduous and coniferous trees and shrubs.

The flightless female moths lay their eggs in a frothy, protective mass that hardens into a sponge-like texture. They typically overwinter in this egg stage.

Caterpillars can cause significant defoliation to trees. Contact with caterpillar hairs can cause skin irritation (urticaria) in humans. They serve as a food source for birds and parasitic wasps.