Armyworms will eat every part of the grass blade, all the way to the beginning of the root. They will leave just particles of chewed leaves where you lawn used to be. A collection of armyworms can destroy an entire lawn within a few days. As armyworms feed, they leave brown patches in the lawn that can appear to look like heat, drought, or chemical stress.

Armyworms actually start out as moths and fly in at night feeding on nectar, mating, and searching for oviposition sites like your lawn. Plants attacked by armyworms include fescue, grain, corn, small grains, sweet potato, beans, turnip, clover, spinach, cucumber, potatoes, tomatoes, cotton, and cabbage. They deposit their eggs in rows or clusters on the lower leaves of grasses or at the base of plants. Their eggs will then hatch in 1 to 2 weeks terrorizing and destroying your lawn!