Since armyworms are susceptible to several different insecticides and are exposed while feeding, chemical control is usually an easy and effective option, according to the North Carolina State University Center for Integrated Pest Management. There are also effective physical control techniques, such as removing weeds or grass from around crops.
Fall armyworms feed primarily on grasses and grain crops, such as oats, barley, wheat, fall rye and corn, according to the University of Illinois Department of Crop Sciences. However, they can also infest many vegetable crops, including cabbage, carrots, beans, onions and peas. Armyworms get their name from the way the larvae march across fields in huge numbers in search of new crops to feed on.
These insects are native to North and South America and range all the way from Argentina to Canada. In the United States, they are primarily found east of the Rocky Mountains. In the United States, the worst crop damage caused by armyworms occurs in the southeastern part of the country. The adult moths spend the winters in southern Florida and Texas, which is why much of the damage from the larvae is restricted to the surrounding areas. Still, the adult moths are strong fliers and soon spread out to much of the rest of the eastern part of the country.