Also known as the tomato fruitworm and cotton bollworm, this caterpillar changes appearance markedly as it grows. Young Corn Earworms are tiny and white, with black heads; older ones are 1 1/2 inches long and green to nearly black in color, with lengthwise stripes and stubby spines along their backs. Finding one of these pests in an ear of corn is dismaying–but the damage is modest, and the ear can be salvaged by cutting off the spoiled tip.