Corn School: Scouting for Three Early Season Pests — Wireworm, Cutworm & Grubs

Skipped plants in a corn row aren’t always due to mechanical error or seedling blights. Early insects like wireworm or grubs can kill plants rather stealthily, leaving gaps in a row or neat leaf damage, while cutworm can clip off a patch of plants overnight. Knowing which insect causes what damage is important when assessing pest levels now, and for planning for next year’s seed treatment selection.

In this Corn School episode, Peter Johnson, independent agronomist, walks us through what you’re looking for in the corn stand, how to tell the difference in feeding damage caused by three key early pests of corn — wireworm, cutworm and the white grub group (chafers and June beetle).

While we can’t yet tell you what the eventual thresholds will be for neonic-seed treatment access in 2016, Johnson says now is a great time for documenting and recording pest levels in each field and areas of each field, and that starts with correct insect identification.