Wireworms In Maple

Identification

• Wireworms are the larval stage of click beetles, also referred to as eyed click beetles. These pests are found extensively in the southern and eastern regions. Common host plants include bean, peanut, potato, corn and cotton. Conoderus lividus is the click beetle species that is usually found on susceptible trees and shrubs like maple. Other trees include hickory and walnut.

Description

• The adult beetles are yellowish brown in color and between ¼- to ½-inch long, with distinct, black to brown markings. The tiny white eggs are sphere shaped, producing white 1.5-mm-long larvae. Mature larvae are about ½-inch long. The wireworm adults that infest trees, C. lividus, are ½- to ¾-inch long and dull brown to gray colored with yellow legs and reddish antennae. The biology and growth traits of all wireworm species are similar.

Damage

• Click beetle females lay their eggs in the roots of infested trees during early spring. Though the eggs hatch within three to 10 days, the larvae stay in the soil for two to six years before reaching the adult stage. The larvae move up and down through the soil, feeding on and damaging roots. Often larvae in all stages of growth are found in the soil at the same time, creating ragged holes in roots. Above-ground damage symptoms include chlorosis, or yellowing foliage, and poor growth.

Management

• Wireworms can only be controlled after the pests have hatched. Common pesticides for control include soil fumigants and liquid and granular formulas. Avoid using products in maple or other plant roots until the presence of pests is established. Recommended chemicals include carbofuron, bifenthrin, chlorpyrfos or diazinon.