What is the Life Cycle of the Bean leaf Beetle?
The Bean Leaf Beetle overwinters as adults under leaf litter at or near soybean fields. Once spring temperatures reach 50 – 55 degrees F, adults become active and seek available host plants such as grasses, soybean plants, and other legumes. The coloration varies from red, orange, tan, or gray and the markings (dots, strips, or both) may vary among individual populations. However, all adults have a black triangle at the base of their forewings. Females are capable of producing 130 to 200 reddish colored eggs which they lay in the upper 5 inches of soil adjacent to plant stems. In 5 to 7 days the eggs will hatch and feed on underground plant parts. Depending on the soil temperature, bean leaf beetle larvae may feed 3 to 6 weeks before pupating into earthen cells. Two generations of bean leaf beetles usually occur in the North Central region. On average, the first adult generation peaks around the late vegetative or early reproductive soybean stage (mid July), and the second generation p
