Velvetbean Caterpillar
Adult - This moth has a wingspan of 30 to 38 mm. The forewings are ash gray, light yellowish-brown, or dark reddish-brown. The hind wings are cinnamon brown with a row of light spots near the margin. When the wings are fully extended, a dark diagonal line extending across both sets of wings is evident.
Egg - The white, prominently ribbed egg is flattened on the lower surface and turns pink before hatching. Its diameter is about 2 mm.
Larva - The sparsely haired larva, 2.5 to 48.0 mm long, varies in color from green to brown or black. It has a light, dorsal stripe bordered by broad, dark stripes, and a broad, white, longitudinal stripe on each side. The larva has five pairs of prolegs and thrashes vigorously when disturbed. Color plate.
Pupa - The pupa, 18 to 20 mm long, is light green or brown and has three pairs of hooked spines at the end of the abdomen.
Host Plants - Although the soybean is the preferred host, velvetbean caterpillars occasionally feed on kudzu, peanut, and velvetbean. They are occasionally reported on cotton, cowpea, coffeeweed, and black locust.
Damage - The caterpillars first feed on tender leaves, gradually move to older leaves, and when foliage is removed, attack tender stems, buds, and small bean pods. Eventually, they can completely defoliate the plants. Velvetbean caterpillars are an annual problem June through September in Florida, Georgia, and Alabama. Further west, infestations are usually less severe. Sporadic damage to late-maturing soybeans occurs in North Carolina from late August into October.
Life History - The velvetbean caterpillar is the larva of a small night- flying moth which overwinters in the tropics and southern Florida. Adults migrate into the Georgia Piedmont during June or July, laying eggs singly on the underside of soybean foliage. The eggs hatch approximately 3 days later. The first instar larvae feed on the egg capsules. The second to sixth instars attack tender soybean foliage when available. After 3 to 5 weeks of feeding, the larvae pupate either in the soil or in folded leaves on the host. One week later, moths emerge. Several generations of the velvetbean caterpillars occur annually in the South.
