Invasive Species Compendium

Detailed coverage of invasive species threatening livelihoods and the environment worldwide

Abstract

Distribution and parasitism of winter moth, Operophtera brumata (Lepidoptera: Geometridae), in western Oregon.

Abstract

In Oregon, Operophtera brumata is distributed throughout the northern region of the Willamette Valley, where it is commonly found on commercial hazelnut, crabapple (Malus sylvestris) and flowering plum (Prunus cerasifera). The adults emerge in early November to December, eggs overwinter, larvae hatch in mid-March and develop through 5 instars, and pupae occur in the soil from May to November. Six species of native parasitoids were reared from field-collected larvae, but parasitism averaged only 4.5 and 12.2% in 1980 and 1981, respectively. The exotic parasitoids Cyzenis albicans and Agrypon flaveolatum were released for biological control of O. brumata in 1981 and 1982. C. albicans was recovered from 4 of 7 release sites. No example of A. flaveolatum has been recovered.