Adult: Varies in color and markings; typically reddish brown with black spots on back and a black band near outer wing margins, up to 1/4 inch long. Larva: Slender white grub.
Beans, peas, cowpeas, soybeans.
Eats regular-shaped holes in leaves; larvae bore into roots.
In all eastern states. Damage usually restricted to small areas.
Bean Leaf Beetles overwinter as adults in leaf litter or weeds in a range of habitats, including forest, pasture, or fallow acreage. They become active as temperatures warm in spring and migrate to legumes, such as alfalfa, peas, and beans where they feed and mate. Eggs are laid in the soil around plants and hatch within one to three weeks. The larvae feed on plant roots until pupation. After emerging from the ground the beetles feed on bean leaves and pods. There are normally two generations annually.
Hand-pick beetles and larvae when found. Clean up all plant debris after harvest.
Spray or dust with rotenone or pyrethrum being sure to cover undersides of leaves. Treat at first signs of injury and repeat in 10 days.
Treat with a registered insecticide when damage appears.
Notice: Because pesticide labels can change rapidly, you should read the label directions carefully before buying and using any pesticides. Regardless of the information provided here, you should always follow the latest product label when using any pesticide. If you have any doubt, please contact your local Extension agent or pesticide dealer for the latest information on pesticide label changes.
Disclaimer: Commercial products named on this site are for informational purposes only. Virginia Cooperative Extension does not endorse these products and does not intend discrimination against other products which also may be suitable.
Revised 3/28/2006