You've paid attention to all the hype about the possibility of black cutworm, and you've looked in your fields. You've found black cutworm in your corn, and asked a neighbor to come look. Using the Purdue University Corn & Soybean Field Guide, you both concur that it is indeed black cutworm larvae that are chewing on some plants. Now what do you do?
You've already taken a big step by getting into the field and finding them, says Dave Nanda, a crops consultant and director of agronomics and technology for Seed Consultants, Inc. Relying on seed-applied insecticides and thinking you couldn't have them in your field because your corn was treated could be a mistake. These insecticides work, but they may not be able to control large numbers of the insect and prevent damage.
The same goes for GMO-hybrids, Nanda says. Certain GMO traits may provide some protection against black cutworm, and it varies from trait to trait. Be sure you know how your trait that you purchased in the seed you bought and planted stacks up for black cutworm control. Again, at least with some GMO products, you may not get enough protection this year if the infestation pressure is large to prevent some form of damage. The larvae must bite into corn plants to get the toxin, so you will see some minimal signs of feeding if you look closely, even if it is effective.
Your best bet if you find cutworms may be a rescue treatment, Nanda notes. Capture, Warrior and generics give good protection for 7 to 10 days. Nanda suggests that if 3% to 5% of the plants are affected, consider spraying the appropriate insecticide as soon as possible.