IPM1019, New February 2003
Armyworm caterpillars (Pseudaletia unipunctata) are present from early summer to fall. They produce three generations per year.
This pest is often referred to as the "true armyworm" to distinguish it from other armyworm species. Full-grown caterpillars are about 1.5 inches long. The head is brown and covered with dark netlike markings. Body color varies from pale-green to gray-green to yellowish brown. On each side is a longitudinal yellow-brown stripe, bordered dorsally with a thin white line. The ventral side of the body is light in color. The abdominal prolegs have a dark stripe. Caterpillars are usually active at night. Host plants include grain and grass crops, wild and weed grasses, vegetable and field crops.
Noctuidae is the largest family in the order Lepidoptera. The body of the caterpillars ranges from smooth with very little hair to clothed with short or long hairs; coloration varies from dull-colored to bright stripes or patches to cryptic. Although many species are found feeding on the foliage of forest or shade trees, they are not considered serious pests. However, several species are damaging to many field, vegetable and fruit crops.
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