Some corn plants are up in Indiana. In fact, corn planting neared completion a week ago in southwestern counties. With the coming of corn emergence comes also insect problems. So far, it's dingy cutworm and what's called the clayback cutworm that have caused issues, not the black cutworm.
Purdue University Extension entomologists Christian Krupke and John Obermeyer note that only black cutworm overwinters in the Gulf Coast region. Moths must fly in and lay eggs. They ride weather currents north in the spring. The moths are often attracted to weedy fields. The green vegetation appeals to them as a place to lay their eggs.
Consultants and crop scouts keep a handle on black cutworm potential for injury by trapping moths in pheromone traps. Some moths have been detected so far in various trapping efforts across the state.
However, the other species don't fly in to Indiana in the spring. They overwinter here. Once vegetation is burned down for planting in the spring, they typically look for a new plant host, such as young corn plants. Dingy cutworms primarily do leaf feeding.
However, in some cases the leaf feeding can be severe. The good thing, the entomologists note, is that the reaction is similar to hail damage. The corn can grow back. Usually there is little or no yield loss if leaves are severely damaged at that stage and then corn grows back normally afterwards.
Treatment is usually not recommended for dingy cutworm, even when this kind of damage is observed. However, the claybacked cutworm can also cut plants. It's known for a mix or feeding on leaves and cutting plants. Entomologists suggest treating it like black cutworm when deciding whether or not treatment for the pest is justified.
The biggest problem is identification. The three can look very similar. Black cutworm has a rougher, bumpier skin. Usually it's up to entomologists to make positive identifications.
Consult your Extension educator is you have a problem with one of these insects before deciding if you should treat the field or not.
Continue scouting for these pests as the corps emerge. Crop scouts will continue to submit data from pheromone traps so that consultants you might work with can stay abreast of if, and know when and where to look for black cutworm activity.