Bean Leaf Beetle

Though the adult varies greatly in color and markings, it is typically reddish-brown to yellowish with black margins and about 5 to 6 mm long. Each wing cover usually, but not always, is marked with three black spots. All bean leaf beetles, however, have a black, triangular-shaped spot on the forward margin of the wings. Eggs are lemon-shaped, orange and about 0.85 mm long. The larva is basically whitish with both ends colored dark brown. Conspicuously segmented, it has six tiny legs near the head. It grows to a length of about 10 mm. Pupa are soft-bodied, white, and about 5 mm long.

The bean leaf beetle is abundant in the southeastern states particularly in the coastal counties. Its range, however, extends into Canada, New York, Minnesota, Kansas, Texas, and New Mexico.

The insect appears to prefer poorly drained clay and organic soils. Hosts of the bean leaf beetle include bean, clover, corn, cowpea, soybean, peanut, and several leguminous weeds. Bean leaf beetles prefer the youngest plant tissue available; when vegetative growth terminates, they will consume tender pod tissue. Pod damage is usually limited to the outer layers of the pod. In addition to the beetles' direct attack, the adults are also known vectors of the bean pod mottle, cowpea mosaic, and southern bean mosaic viruses.

For control products and more information please see our Pest Beetle Control page.