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What is EAB?

EAB Description and Life-cycle
The emerald ash borer is a small, metallic wood-boring beetle, in the same genus as the Bronze Birch Borer (Agrilus anxius). Adults are approximately 1/2 inch long and 1/8 inch wide, and have a metallic green color. Larvae are cream-colored, flattened, and grow to approximately one inch in length. Typically, EAB requires a one-year life cycle. Adult beetles emerge in the spring and can be found from mid-May to early August. The adult EAB exits the tree through a distinctive, D-shaped exit hole, about 1/8 inch in size. After mating, females lay their eggs on the bark surface and in bark cracks. Larvae hatch in the summer and tunnel into the ash tree, feeding on the phloem and outer sapwood. The larvae create very distinct, S-shaped serpentine galleries under the bark, which disrupts the movement of water and nutrients through the tree. Full-grown larvae over winter in chambers in the sapwood. They pupate in April and May, before emerging as adults