Alfalfa Webworm – Loxostege cerealis

Alfalfa Webworm   Scientific Name: Loxostege cereralis Common Name: Alfalfa Webworm Appearance: In the early life stages, Alfalfa webworms are greenish-yellow in color. As they mature, they attain dark brown to green color. They have a white stripe running down the middle of their body and six black spots on each segment. Caterpillars reach up to the size of 38mm. Adult Alfalfa webworms are mostly seen resting on the grass in the lawns. It has a wingspan of 1 inch and mottled gray color with black markings. Host Plants or Food: Alfalfa webworms feed on a number of plants, mainly including Alfalfa, Sugar beet, cabbage, carrot, beans, pigweed, lambsquarter and common mallow. Territory: Throughout North America. Mode of Damage: Alfalfa webworms are leaf chewers; the caterpillars skeletonize the leaves and web the leaves together as they eat them. Habits and Life History: Alfalfa webworms are found in the web cocoons they make by webbing the leaves. Alfalfa webworms spend their winter as mature caterpillars in the soil or under plant debris. These larvae pupate in early Spring, and the adult emerges in May. Adults lay eggs, which hatch into larvae. These larvae feed on the leaves of the plant for 3-5 weeks and reach up to 38mm. Larvae undergo pupation and then mature into adult Alfalfa webworms. This second generation is produced in June-July and then 3^rd generation in September. They produce almost three generations per year.