See fact sheet on Cucumber Beetles
Adult: Pale yellow to orange with 3 black stripes down back; black head. 1/4 inch long. Larva: White, slender, brownish at the ends; up to 1/4 inch long.
Cucumber, muskmelon, winter squash, melon, pumpkin and watermelon.
Adults feed on leaves, stems, and fruit, and spread bacterial wilt and squash mosaic. Larvae bore into roots and also feed on stems at or below soil line. Insects usually attack young plants. Damaged plants wilt and sometimes die.
East of Rocky Mountains; related species are found in some western states.
Unmated striped cucumber beetle adults migrate south for the winter or overwinter in plant debris or rotting wood. They begin feeding on altenate hosts when the soil temperature reaches about 55 F in the spring. Beetles move to cucurbits as soon as plants come up or are set out, and begin feeding and mating. Within a few days eggs are laid and larvae emerge in about ten days. Larvae feed on plant roots until pupation. Adults appear in about a week to ten days and begin the lifecycle again.
Start seeds under fine netting and place cones made from window screening over emerging plants. Protective materials can be removed once plants grow large enough to tolerate damage.
A botanical insecticidal spray or dust may be effective. Parasites of the striped cucumber beetle includes a tachinid fly, braconid wasp, and a nematode. Of the several predators that prey upon this pest the the soldier beetle, Chauliognathus pennsylvanicus DeGeer, is considered most important.
Caution: Make application in late afternoon. Pesticides may kill bees when applied between 10 a.m. and 2 p.m.
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.
Prepared by Alexandra Spring and Eric Day (Modified from a publication by the USDA)