Stalk borers are very common pests of corn, especially in rows next to grassy waterways and fence lines. These rows often are stunted in height. Young larvae have cream-colored stripes along the center of the back and along each side. A lateral pair of dark brown to purple stripes also extend the length of the body, but they combine to form a purple heart section directly behind the true legs. The dark stripes and purple heart fade in older larvae.
All larvae have a dark stripe on each side of the head.
Moths lay eggs in grassy or weedy areas during late summer and these hatch the following spring. There is one generation per year. Hop vine borers are stem-tunneling caterpillars that kill young corn plants. They attack the underground portion of corn and tunnel up from underneath the plant to hollow out the base of the stalk. This injury is unique and should not be confused with black cutworm, which cuts plants, or stalk borer, which tunnels in the above-ground stalk.