Cyclical-outbreak
Guides
Orgyia pseudotsugata
Douglas-fir tussock moth
A western North American tussock moth known for periodic population outbreaks that cause significant defoliation of conifer forests. Males are winged and grayish-brown with feathery antennae, while females are flightless with rudimentary wings. Caterpillars are distinctive with red spots, white spines, and prominent red-tipped white tussocks. The species undergoes cyclical outbreaks every 8-12 years that can persist for up to four years.