Corn is the preferred host plant of corn earworm, which has over 100 alternate hosts. In the mid-west, corn earworm is typically a late season pest of sweet corn, though field corn is also a common host of this pest.
Male moths are typically lighter in color than females.
Females lay from 350 to 3,000 yellowish-white eggs singly on corn silk and foliage. Before hatching, eggs develop a reddish-brown band. Larval coloration ranges from brown to green to pink. Corn earworm larvae can also be distinguished from other caterpillars by the black tubercles that cover their bodies, the 3-4 stripes running dorsally down their bodies, and their tan heads. Corn earworm larvae typically feed within the ear on developing kernels.