Public Works and Environmental Services

CONTACT INFORMATION: Our administrative offices are open 8 a.m. – 4 p.m. Mon - Fri
703-324-1770 TTY 711
12055 Government Center Parkway
Suite 518, Fairfax, Va 22035
Brian Keightley
Division Director, Urban Forest Management

Emerald Ash Borer in Fairfax County

Click photo to enlarge

Emerald Ash Borer in Fairfax County
Adult emerald ash borer
Photo by: David Cappaert,
Michigan State University
Emerald Ash Borer in Fairfax County
Emerald ash borer larvae
Photo by: Brian Sullivan,
USDA APHIS PPQ
Emerald Ash Borer in Fairfax County
Emerald ash borer larva
Photo by: David Cappaert,
Michigan State University

Emerald Ash Borer Background

The emerald ash borer (Agrilus planipennis), also known as EAB, is a northeastern Asian beetle that was unintentionally introduced into North America via packing material in 2002. EAB does not quickly spread great distances on its own. It is, however, easily transported from infested to uninfested areas in ash firewood, wood chips, and nursery stock. Unfortunately, as is the case for most newly introduced species, EAB arrived in North America without any 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 including Fairfax County and most of Virginia.

EAB 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.

EAB in Fairfax County

Fairfax County Urban Forest Management Division (UFMD) works cooperatively with the U.S. Department of Agriculture (USDA) 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 uninfested areas. The 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 EAB larvae and eggs. Currently, there are still several living ash in the area. These may be unusually resistant to the attack of EAB, and therefore may be a valuable resource for research or as a source for seeds. Insecticidal injection methods have been used to protect a limited number of these trees on County property and in public spaces.

What Can I Do?

UFMD 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 when deciding what tree species to plant visit Tree Selection.

Any dead trees or trees with dead branches should be managed proactively because they can be hazardous. For information about removing trees, please visit Tree Removal. Ash trees affected by EAB may randomly fail faster than other trees due to brittle wood. It is important to recognize this issue.

Signs and Symptoms of an EAB infestation

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Emerald Ash Borer in Fairfax County
Adult emerald ash borer
Photo by: Fairfax County
Emerald Ash Borer in Fairfax County
Larval Galleries
Photo by: Fairfax County
Emerald Ash Borer in Fairfax County
"D" shaped exit holes
Photo by: Fairfax County
From: Ecolandscaping.org. Woodpecker feeding or blonding caused when the outer bark of a tree is stripped by woodpeckers revealing the lighter bark beneath
Woodpecker feeding or blonding caused when the outer bark of a tree is stripped by woodpeckers revealing the lighter bark beneath.
From: Ecolandscaping.org.
Emerald Ash Borer in Fairfax County
Vertical bark splitting caused by emerald ash borer
Photo By: Michigan Department of Agriculture
Emerald Ash Borer in Fairfax County
Canopy dieback caused by emerald ash borer infestation
Photo By: Steven Katovich
Emerald Ash Borer in Fairfax County
Epicormic shoots caused by emerald ash borer infestation
Photo By: Pennsylvania Department of Conservation and Natural Resources

More information about EAB can be found at EAB Network - Home (emeraldashborer.info)

Forest Pest Branch Biological and Chemical Control Efforts

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Eulophid wasp Tetrastichus planipennisi
Eulophid wasp (Tetrastichus planipennisi)
Photo by: David Cappaert, Bugwood.org
Encytid wasp Oobius agrili
Encytid wasp (Oobius agrili)
Photo by: Debbie Miller, USDA Forest Service, Bugwood.org
staff releasing adult parasitoids
Staff releasing adult parasitoids
Photo by: Fairfax County
staff release parasitoid adults and eggs
Staff release parasitoid adults and eggs
Photo By: Fairfax County
Staff injecting ash at County school
Staff injecting ash at County school
Photo By: Fairfax County
staff injecting ash at County park
Staff injecting ash at County park
Photo By: Fairfax County
Fairfax Virtual Assistant