Emerald ash borers (EAB) are originally from eastern Russia, northern China, Japan, and Korea. The original infestations were found in 2002 near Detroit, Michigan, and traveled to Maryland and northern Virginia from Michigan in some infested nursery trees. Their populations are increasing rapidly because they have no effective predators here. They have already killed tens of millions of trees in North America, and show no signs of stopping. By the end of 2011 they will have killed more trees than Dutch Elm Disease.
EAB attacks all species of Ash (Fraxinus spp.
), and causes 99% mortality. The most damaging stage of their life cycle is the
, when they tunnel around under the bark of the tree, affecting the tree's ability to transport nutrients and water. After that they pupate, emerge as adults through distinctive
1/8 inch D shaped exit holes
, disperse, mate, and lay eggs on the bark of ash trees, starting the process all over again.
EAB in Prince William County
EAB was first found in Prince William County in 2010. Subsequent years of trapping (using large sticky purple traps) indicated that Emerald Ash Borer is present across the county - trapping is no longer being conducted by our branch. Many ash trees in the county show symptoms of EAB; epicormic branching (water sprouts), canopy die back, woodpecker damage, and bark splits. The 1/8th inch diameter D shaped exit hole and larval galleries are diagnostic signs that EAB is present. Visit www.emeraldashborer.info for additional information.
Pesticides can be applied to individual trees to protect them against EAB. Trees must be healthy and have at least 30% of their leaf canopy remaining to be a good candidate for treatment. Pesticides must continue to be applied on a scheduled basis for protection. Label directions and rates must be followed, and different pesticides are available to homeowners or state certified pesticide applicators. Many ash trees will not be treated with pesticides; some trees may be too unhealthy, too small, or pesticides may be cost-prohibitive or undesired. Almost all ash trees that are untreated will continue to decline and die. Trees should be monitored carefully- we recommend contacting a certified arborist to evaluate tree risk and to handle tree removal as needed.
Unsure if you have Ash trees or have questions about EAB or the next steps you can take? Contact us.