4 (1 = rare 5 = annual)
3 (1 = very little damage 5 = plants killed)
Eggplant, bean, radish, pepper, potato, tomato, spinach, and sweet corn.
Several species of flea beetles feed on a variety of plants in Illinois. They overwinter as adults in leaf litter, hedgerows, windbreaks, and wooded areas. In early spring, the adults become active and mate. Depending on the species, females will lay single eggs or clusters of eggs in small holes in roots, soil, or leaves of many different plants. In home gardens, they are common on crucifers, including radishes, broccoli, cabbage, and turnips, eggplant, peppers, tomatoes, potatoes, spinach, and melons. Following egg hatch, small white larvae feed on the roots of the newly planted seedlings, usually causing little to no damage to the plants (with the exception of potato flea beetle larvae). Larvae then pupate in the ground, and a few weeks later, a new generation of adults emerge and feed on foliage, just as the previous generation did. There are usually one to two generations per year.
There are many species of flea beetles. Those most common on vegetables are black, 1/16- to 1/8-inch long adult beetles that may have light-colored stripes. They jump and fly when disturbed. The spinach flea beetle is almost 1/4 inch long, with a reddish neck. Although the larvae of most flea beetles live on roots, the spinach flea beetle larva lives on the leaves, is gray, and grows to be 1/4 inch long.
The adults eat tiny, pin-sized holes in leaves of eggplant, radish, bean, potato, tomato, and pepper. Pits may be eaten into the leaves; these pits later turn brown. Spinach flea beetle adults and larvae eat larger holes in spinach. Root-feeding larvae are rarely a problem. On sweet corn, corn flea beetle transmits Stewart's wilt.
On cole crops, seedlings and transplants are the most critical stages for flea beetle control. Plant sweet corn varieties that are resistant to Stewart's wilt. For greens, treatment may be needed to avoid noticeable damage.
Filed under plants: Vegetables
Filed under problems: Insects Damage