ESTABLISHMENT OF THE SQUASH BUG PARASITOID, TRICHOPODA PENNIPES FABR (DIPTERA, TACHNIDAE), IN NORTHERN CALIFORNIA

The squash bug, Anasa tristis (De Geer) (Hemiptera: Coreidae), is an i mportant pest of squash and pumpkin plants in California. Its pest sta tus is partially due to a lack of specific nymphal or adult natural en emies in California. A nymphal-adult parasitic fly, Trichopoda pennipe s Fabr. (Diptera: Tachnidae), commonly associated with squash bugs in eastern United States, was imported and released beginning in 1992 at several locations in Yolo, Solano, and Sacramento counties in northern California. This fly has successfully overwintered at four locations and has been recovered at two locations three years after initial rele ases.