Choristoneura occidentalis

Choristoneura occidentalis is also known as the western spruce budworm. It is common throughout the Rocky Mountain Region. The forewing is 12- to 18-mm long. The larvae feed on spruce needles and the species experiences periodic outbreaks of immense populations. Larvae of this species can cause massive defoliation when outbreaks occur, which lead to insecticide applications that help keep the population under control.

Order: Lepidoptera
Family: Tortricidae
Species: Choristoneura occidentalis

Photograph: © 2006 RKD Peterson
Date of Photograph: 23 July 2006
Location: Montana, Gallatin Co. (45^o43'41" N 111^o08'11" W)

Choristoneura occidentalis © 2006 RKD Peterson