Scouting and Management for Wireworms

March 1, 2023

Wireworms are the larval stage of click beetles (Figure 1). These larvae can affect corn stands by tunneling into young corn seedlings and killing developing corn (Figure 2). Often, heavily manured fields, or fields with excess organic matter, were areas that typically had more pressure. Corn following sod has the highest risk of wireworm injury as larvae may take up to six years to complete development. Soils that are cool and wet during early spring can be more susceptible to wireworm damage as well, due to slower seedling growth.

Characteristic yellowish brown, hard-shelled wireworm larva.
Figure 1. Characteristic yellowish brown, hard-shelled wireworm larva.


Wireworm Deadheart
Figure 2. Wireworms injure corn seedlings by boring into the stem below soil line and damages or kills the growing point. The injury results in a “dead heart” appearance.

Insecticide seed treatment has been a strong tool in wireworm management, allowing the corn to develop normally under moderate wireworm pressure. Prior to widespread use of insecticide on the seed, replanting due to wireworm damage was a much more common occurrence as there is no rescue treatment. Fields at risk for high wireworm pressure include those with a history of wireworm damage, or first year corn after sod. In these scenarios, a soil applied insecticide may make agronomic sense. Bait stations with wheat, corn, or other seeds can also be used prior to planting to determine if wireworms are present.

If you suspect wireworm damage in your field, contact your Channel Seedsman. From there, your Seedsman can evaluate plant stands, assess wireworm pressure, and help determine if any actions are necessary to help maintain the yield potential of the field.


Channel Agronomist
Daniel Lundeen

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