Emerald Ash Borer in Fairfax County

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Emerald ash borer (EAB) is a north-east Asian beetle that was unintentionally introduced into North America in packing material in 2002. Once introduced, EAB does not quickly spread great distances on its own. It is, however, easily transported from infested to noninfested areas in ash firewood, wood chips, and nursery stock. Unfortunately, as is the case for most newly introduced species, EAB arrived in North America with none of its Asian predators, parasites or diseases ready to control its populations here. EAB therefore has rather quickly made itself at home in the northeastern United States, Fairfax County and most of Virginia included.

The beetles lay their eggs on the bark of ash trees. The emerging larvae then burrow under the bark to feed on the trees’ vital vascular tissues. Increasingly unable to transport water and nutrients, trees will typically die in 3 years. EAB prefers all species of ash and is currently almost always fatal without treatment.

Fairfax County Urban Forest Management Division (UFMD) therefore discourages the planting of ash trees for landscaping purposes. Builders will not receive tree canopy credits for planting ash on development sites within the county, and residents are encouraged to plant a variety of other native species instead of ash. For a good place to start visit Tree Selection. For information about removing trees, please visit Tree Removal.

Fairfax County UFMD works cooperatively with the U.S. Department of Agriculture and Virginia Department of Agriculture and Consumer Services to minimize the long-term impact of EAB in the County, and to slow their spread to noninfested areas. USDA has provided some of EAB’s natural enemies, tiny stingless wasps, as biological controls. These wasps are harmless to humans and the environment, but they’re highly effective at killing the EAB larvae and eggs. In addition, insecticidal injection methods have been used to protect a limited number of trees on County property and public spaces.

Signs and Symptoms of an EAB infestation

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