History and Lifecycle

History

Emerald Ash Borer (Agrilus planipennis) is an exotic wood boring beetle discovered in southeast Michigan in the summer of 2002. Emerald Ash Borer (EAB) is believed to have arrived in Michigan on wood packing material from Asia 10-15 years ago. The beetle which only attacks ash trees (Fraxinus sp.) is capable of killing trees of all sizes, including trees that appear to be healthy; the beetle has killed over 15 million trees in southeast Michigan to date.

To prevent and control the spread of EAB, the Michigan Department of Agriculture has established a series of quarantines within the state which regulates the movement of ash, ash products, EAB and any species of hardwood firewood. Please visit the Michigan Department of Agriculture's EAB web page for detailed information about quarantine restrictions at http://www.michigan.gov/eab.

Life Cycle

EAB generally has a one year life cycle, but may require two years in areas where the EAB population is low. The adult EAB emerges from ash trees in May and June, leaving D-shaped exit holes in the bark. From mid-May to mid-August adults feed on ash tree leaves, mate and the females lay eggs (individually) in the bark crevices. The female can lay 60-90 eggs during her lifetime; adults live about 3-4 weeks. Eggs hatch 7-10 days after being laid and the larvae tunnel into the bark from May to August. Larvae begin feeding and tunneling in the cambium under the bark creating s-shaped galleries from August to October. The larvae stop feeding in October/November and spend the winter under the bark until spring when they begin to pupate.