The Soybean Looper, Pseudoplusia includens, is an abundant plusiine caterpillar that is a pest of soybean, sweet potato, peanut, cotton, tomato, peas, tobacco. They mainly feed on the soybean foliage, but sometimes feed on pods as well. The young larva starts at the interior lower portion of the leaf surfaces, but as they mature they move towards the top of the leaf surfaces.
Characteristics The name looper comes from the way their larval body humps up in the middle in a looping motion while walking. The larva are light to dark green with light horizontal stripes running along each side of the body and have two pairs of abdominal prolegs and an anal pair. The rear of the body is thick and tapers down towards the head. They can reach a length of 1.3 inches and some have black legs or black markings on the head and body. The pupae are a 1/2 inch long and range in color from white to green. Moths are from brown to black with a wingspan of 1 or 1.5 inches. The forewings are brown with golden and silver markings near the center.
Life Cycle They overwinter and come out in June. The eggs are laid singly on the underside of leaves and the larva hatch in three days. They feed for two to three weeks and then pupate in silk-like cocoons on the underside of the host plants leaves. The pupae develop for a week.