Velvetbean caterpillar

Most recently reviewed by: Suhas Vyavhare (2021)

Common Name(s): Velvetbean Caterpillar

Description

The velvetbean caterpillar, Anticarsia gemmatalis (Hubner) is a foliage-feeding pest of soybean. Heavy infestations of velvetbean caterpillar are capable of causing significant economic losses through defoliation if left unchecked. Larva range in color from pale yellow-green to black with white or yellow strips running lengthwise along the body and can be identified by their vigorous wiggling and twisting when disturbed. They have four pairs of abdominal prolegs, plus one pair at the end of the abdomen. Velvetbean caterpillar moths are variable in coloration with wings mottled usually with a diagonal black line across the wings when fully extended. Adult moths will often flutter around infested soybean fields when disturbed.

Origin and Distribution

Velvetbean caterpillars do not overwinter in Texas, but large numbers migrate to Texas from Central and South America annually primarily infesting soybeans, primarily in the eastern portion of the State. Other populations in the southeastern US are common.

Habitat & Hosts

While soybean is the primary host for the velvetbean catyerpillar, it can be found feeding on foliage of peanut, kudzu, velvetbean, horse beans, cotton, cowpea, coffeeweed, black locust, hairy indigo, lespedeza, and white sweetclover.

Life Cycle

Velvetbean catyerpillar exhibit complete metamorphosis. Moths deposit ribbed, light green eggs on soybean leaves, pods and stems singularly or in groups of up to 3. Larva will progress through 6 instars, growing larger with each molt or stage, feeding on an increased portion of the leaf as they age. Once all instar stages have completed, caterpillars then pupate in the soil. Moths emerge around 7 days later in the summer but could take up to 11 days in cooler weather in the fall. Once established, each successive generation will increase locally in numbers with peak populations occurring in eastern Texas during summer and early fall.

Management

If you live in the State of Texas, contact your local county agent or entomologist for management information. If you live outside of Texas, contact your local extension for management options.

Both visual inspection and sweep net are effective methods of sampling for velvetbean caterpillar. Action thresholds in soybean are based on percent defoliation and presence of insects. Avoiding late planting or using early maturity soybean varieties can help avoid late summer and fall buildup of this pest. There are several insecticide options available for the control of velvetbean caterpillar. Consult your local Texas A&M AgriLife Extension county office for best local control methods.

Related Publications

Managing Soybean Insects in Texas, NTO-045 https://extensionentomology.tamu.edu/resources/management-guides/managing-soybean-insects-in-texas/soybean-insects-mid-to-late-season-pests-v8-to-maturity/