Corn Wireworm


Wireworms, the larvae of click beetles, feed on the roots and underground parts of corn plants, leading to stunted growth, reduced vigor and lower yields. Wireworms can cause:

• Wilting or yellowing leaves • Stunted plant growth • Uneven emergence • Small holes or tunnels in plant roots Early detection of wireworm infestations is important as damage may not always be immediately visible above ground. If left unmanaged, they present a serious threat to corn crops by causing significant yield losses.

Regular scouting, early detection and proactive chemical control options with products like Willowood Lambda-Cy 1EC** and GCS Bifenthrin 2EC** can help mitigate wireworm damage and improve the likelihood of a successful corn harvest.

(Image Credit: Kansas Department of Agriculture,


How to Identify Wireworms

Wireworms typically have a slender and cylindrical body shape, a hard and shiny exoskeleton, and segmented bodies. They range in color from yellowish-brown to reddish-brown and vary in length from a quarter of an inch to one and a half inches.

However, wireworms are often challenging to identify as they spend most of their life cycle hidden beneath the soil, so farmers should dig around the base of affected plants to reveal potential infestations.

(Image Credit: Frank Peairs, Colorado State University,

Regions Affected by Wireworms

Wireworms can be found in various regions across North America, but they are particularly prevalent in areas with heavy clay soils or where grassy or sod crops have been grown in the past.

While farmers in the Midwest, Great Plains, or parts of the Pacific Northwest are more likely to encounter wireworm problems, they can be present in any corn-growing region.

Timing of Wireworm Impacts

Most active during the early season, wireworms typically emerge in late spring or early summer. They overwinter in the soil as larvae and become more active as temperatures rise, feeding on the roots of corn plants. This period of heightened activity poses the greatest threat to the health and productivity of corn crops.


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