In fact, the moths may continue their migration the following night into Illinois, Minnesota, or Wisconsin. The first cutting was reported in eastern Iowa on May 22. This first cutting date was nearly 5 weeks after the first corn was planted, which is an extremely long time to expect an at-planting insecticide to still be effective. The last serious cutworm outbreak occurred in Iowa was 1984. Recent information strongly suggests that the threat of black cutworm damage on a large scale is overrated.
Costs also vary from dealer to dealer.
Insecticide performance guarantees One company may guarantee that its insecticide provides control of cutworms when applied as a preemergence treatment, whereas another company may state that with one preplant application for cutworms, you have one less problem to worry about. Do not be lulled into a false sense of security with insecticide guarantees or claims. Any guarantee or claim is subject to the condition that the field must be scouted for insect damage. Just because an insecticide was applied to the field at planting does not preclude the possibility of crop injury by the insects later in the season. Alternative to insecticides There is a better alternative to black cutworm management than buying unnecessary insecticide and increasing on-farm input costs.