By Veronica Yurchak
Bean leaf beetles (BLB), C. trifucata, are showing up in snap beans in some areas of the Eastern Shore. This sporadic pest has the potential to cause serious damage to snap beans, soybeans, and other legume crops. Adult beetles are relatively small and range in color from yellow to red with varying numbers of black spots along their wing covers. The distinguishing characteristic is a small black triangle on the upper side where the wing covers meet. This can help distinguish this pest from the spotted cucumber beetle, which is considered only a minor foliar pest of legumes. There are typically three generations per year, with the first generation of overwintering adults emerging early in the season around the same time as snap bean planting.
Source : umd.edu