Adults: Black with reddish-orange and yellow markings; flat; shield-shaped; up to 1/4 inch long. Nymphs: Resemble adults but are smaller, more oval with red and black markings. Eggs: Barrel-shaped; white with black rings; laid on the undersides of leaves.
Brussels sprouts, cauliflower, cabbage, kale, kohlrabi, lettuce, collard, mustard, radish and turnip.
Adults and nymphs suck sap. Feeding by harlequin bugs causes yellow or white blotches to appear on leaves. Plants wilt, turn brown and die
Throughout United States, particularly in the south.
In Virginia harlequin bugs overwinter as adults in plant debris. Adults become active in early spring and lay eggs on the undersides of leaves for a period of about two weeks. Eggs are characteristically placed in two rows of about a dozen eggs each. Each female lays about 150 eggs. In cooler temperatures the eggs hatch in about three weeks, but as temperatures rise eggs can hatch in less than a week. Nymphs feed and mature through five instars in about six to eight weeks. Multiple generations occur annually in Virginia.
Hand-pick adults and crush egg masses (effective if done often). Eliminate weedy areas around garden in early spring. Conduct thorough post-harvest clean up; being careful to remove all plant debris.
Dust with pyrethrum or other botanical insecticide.
Treat with a registered insecticide. Follow all label instructions, precautions and pre-harvest intervals.
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)