Perhaps you normally shrug off comments about now-and-then pests like black cutworm. This could be a costly year to ignore the threat the pest can pose to your corn crop. Purdue University entomologists John Obermeyer and Christian Krupke recently reported that there have been black cutworm moth trap counts this high in Indiana this early in the season as there was this year. What's more, there haven't been freezes once they got here that would likely take them out. The bottom line is that even if you normally don't pay much attention to hype about black cutworm, this year you should. It's not hype this time around.
The entomologists believe that the moths round into Indiana form the Gulf states where they overwinter on strong storm patterns around March 23. That's based on interpreting data from cooperators who catch moths in pheromone traps around the state.
Fields that are at most risk are ones that are green or were green and stay green, especially with fall annual weeds. Black cutworms actually don't like to feed on corn plans. It's the plant of last resort as a food for the larvae, but if nothing else is available, they will feed on corn.
One strategy is to spray weedy fields, or if you have already sprayed, wait a week or more before planting into them. Another option is clean tillage and then wait before planting. If the larvae have no food source, they may starve before corn plants emerge, Fields where you plant into green vegetation will be at highest risk.
Seed-coated insecticides may not be sufficient to control cutworms if pressure is high from the pest, the entomologists note. Certain GMO traits that list black cutworm suppression may also not hold up to a large infestation and high pressure levels from the pest. Also be wary if you applied an insecticide with a burndown, and it's been more than 7 to 10 days between application and planting. Those are contact insecticides which can break down quickly. Expecting them to last all spring is simply a falsehood- it won't happen, the entomologists say.
Timely scouting and rescue treatments may still be the best solution, they note. They advise growers not to panic, but instead to scout and be ready to spray a rescue treatment if necessary.