Click Beetles (Wireworms)

Elateridae (Alaus sp.)

Description

“Click beetle” adults are elongated, parallel-sided, and somewhat flattened. They vary in size (6 mm-40mm) and colour by species. When they are disturbed, they lie on their backs feigning death, and then suddenly snap their thoracic segments to flip their bodies in the air and right themselves with an audible “click”. Hence their name.

“Wireworms” are the yellowish soil-dwelling larvae of click beetles. Their name comes from the long, slender, and cylindrical shape of the body. Larvae have three pairs of tiny true legs behind the head.

Life Cycle

The biology of click beetles varies by species. In general, adults and larvae overwinter in the ground. In spring, adult females dig borrows near plant roots and lay eggs. The eggs hatch after 3 to 10 days and the emerging larvae feed on the roots of the host plant. The larvae develop over a period from several months to 6 years. The last instar larvae pupate in the cells in the soil in late summer or fall. In a few weeks, the adults emerge. Some species can complete two generations in one year, but most take one or more years to complete one generation.

Damage

Wireworms are destructive plant pests and live in the soil for two to six years. They attack seeds, and plant roots such as potatoes, carrots, beets, beans, cotton, corn, wheat, melons, onions, and strawberries. This can cause the plants to wilt and die. In contrast, click beetles do not damage plants, but are more of a nuisance. Their loud clicking sound and sudden flips can be staggering.

Control

Advice