OVERWINTERING OF TUBER FLEA BEETLES, EPITRIX TUBERIS GENTNER (COLEOPTERA: CHRYSOMELIDAE), IN POTATO FIELDS

Early season infestations of adult tuber flea beetles, Epitrix tuberis Gentner, usually are concentrated at the edges of potato fields, and it generally has been assumed that they move into potato fields from the outside inward. This edge-effect suggests that tuber flea beetles overwinter outside potato fields, and other species of flea beetles have been reported to behave similarly (Wolfenbarger 1940; Dominick 1971; Burgess 1981). This may not be true of E. tuberis, however. Hoerner and Gillette (1928), in Colorado, noted that potatoinfesting flea beetles [probably E. cucurneris (Harris), E. subcrinata (Lec.), or E. tuberis] often congregated under piles of old potato vines in potato fields, and Hill and Tate (1942) observed flea beetles feeding on cull tubers in a potato field after harvest. These observations suggest, but do not confirm, that some flea beetles including E. tuberis may remain in harvested potato fields during winter.