Common stalk borer larvae are usually very active when handled. The common stalk borer is native to North America and is known to attack 176 different plant species. An increase in no-till corn acreage has increased common stalk borer incidence and problems. Adult moths are grayish brown in color with small white spots along the front edge and along the tips of the fore wings. The hind wings are a pale gray-brown.
Wing span is about one inch.
The female moths lay their eggs in late summer and fall. Preferred egg-laying sites are on weedy hosts. The stalk borer over winters in the egg stage. Eggs begin hatching in late April and early May and the tiny borers immediately burrow into grasses or other weeds. When these grasses die, or the borers become too big, they emerge at night and tunnel into new hosts, including corn.