Corn Insects

Black Cutworm Caterpillars Are Actively Feeding in South Dakota

We received numerous reports this week of small holes in V1-V2 corn plants. The holes are the result of early instar cutworm caterpillar feeding and, more specifically, black cutworm caterpillars. After hatching, black cutworm caterpillars initially feed on the leaves. As they develop and become larger, they pose a clipping or cutting threat to corn.

Watch Corn for Bronzed Cutworm Activity

Bronzed cutworms are not a common pest of corn in South Dakota. However, they can become an issue when corn is planted into areas that were previously grassland. Like its name implies, bronze cutworms feed on corn above the soil surface, which often results in cutting or clipping.

Monitor Newly Emerged Corn for Black Cutworm Activity

There are several important insect pests that can severely injure corn during the early vegetative stages. One of these pests is the black cutworm. Although black cutworm caterpillars injure corn by feeding on leaf tissue, the serious damage occurs when caterpillar feeding results in the cutting of young corn plants.

How to Identify Common Stalk Borers and Thresholds

As corn is being planted, it is important to remember that there are insect pests capable of injuring young, vegetative corn. One such pest is the common stalk borer. Although common stalk borer outbreaks are sporadic, when present in high numbers they can cause significant yield loss.