How to Manage Pests
UC Pest Management Guidelines
The potato flea beetle is a small (0.065 inch), shiny, black beetle. The threespotted flea beetle is two to three times larger and has an orange colored thorax on which are three prominent dark spots. The palestriped flea beetle is about twice as large as the potato flea beetle. It is dark brown and has a longitudinal creamy white stripe on each wing cover. The desert corn flea beetle is 0.125 inch long and brownish with two pale yellowish stripes along the wings.All of the flea beetles have enlarged hind legs and jump vigorously when disturbed, thus the name flea beetle.
Damage is caused by adults. Feeding by the potato, palestriped, and threespotted flea beetles consists of numerous small rounded or irregular holes eaten in leaves so that leaves appear to have been peppered with small shot. Feeding by the desert corn flea beetle causes yellowish white feeding scars about 0.125 to 0.5 inches long along the leaf veins.In young plants particularly, the feeding damage can be very serious and can result in death. In addition to adult damage, larvae of the palestriped flea beetle feeds on roots of young plants as well as on germinating seeds.
No economic thresholds are available but treatments, especially on young plants, should be considered if damage reaches a moderate level. Keep fieldsweed-free, particularly of field bindweed and mustard, which are preferred hosts of flea beetles. Heavily damaged fields should be replanted.
UC IPM Pest Management Guidelines: Corn