Worm - Armyworm

Armyworm

Armyworms get their name from their behavior of moving across fields in an army-like fashion. As larvae consume available food sources, they migrate as an army to new host plants. Though they feed primarily on grasses (oats, wheat, fall rye, corn, barley, and forage grasses), they can be a pest of some vegetables (bean, cabbage, carrot, onion, pea, pepper, radish and sweet potato).

Source:  University of Illinois