Save Your Ash


Emerald Ash Borer

Save your Ash, Knoxville! The emerald ash borer has been reaping havoc throughout the Eastern United States for many years now.  Emerald ash borer (EAB), Agrilus planipennis, is an exotic beetle from Asia that attacks ash trees. The EAB has killed over 60 million ash trees since it was first discovered in southeastern Michigan near Detroit in the summer of 2002. The adult beetles eat the ash foliage and the larvae feed on the inner bark of ash trees. The larvae prohibit the tree’s ability to transport water and nutrients, which kills the tree. The Emerald Ash Borer is native to Asia and was likely transported in wood packing material to the United States. Unfortunately, Ash trees in your own backyard are facing infestation. Twenty two trees in Victor Ashe alone have become infested by the EAB.

Current Situation

The emerald ash borer (EAB) was identified in Tennessee at a truck stop on I-40 in Knox County in July, 2010. By 2011 six Tennessee counties, Blount, Claiborne, Grainger, Knox, Loudon, and Sevier were under emerald ash borer quarantine. In 2012, 12 more counties were added to the original 6: Anderson, Campbell, Cocke, Greene, Hamblen, Hancock, Hawkins, Jefferson, Monroe, Roane, Smith, and Union. In 2013, 3 additional counties were added: Hamilton, Jackson and Scott. In 2014,18 new counties were added including Davidson, Fentress, McMinn, Morgan, Polk, Putnam, Rhea, Sullivan, and Washington where EAB was positively detected, and Bradley, Carter, Clay, Johnson, Macon, Meigs, Overton, Pickett, and Unicoi where EAB is likely present based on close proximity to positive counties. By October 2015, eight (8) new couties were added and included Bledsoe, Cumberland, Franklin, Marshall, Rutherford, Trousdale, Williamson and Wilson. This brings the total number of counties quarantined for EAB to 47.

According to the USDA Forest Service and the Tennessee Division of Forestry, an estimated 271 million ash trees in Tennessee, amounting to $11 billion value, could potentially become infested with the emerald ash borer.

Annual Survey

USDA Animal and Plant Health Inspection Service, along with the aid of the Tennessee Department of Agriculture, Tennessee Department of Environment and Conservation,  and the University of Tennessee organizes emerald ash borer trapping activities each year. These traps are large, purple triangular traps that resemble a box kite and are hung in ash trees throughout Tennessee. In 2014, 1,224 purple traps were placed across the state of Tennessee.


The adult emerald ash borers are about 1/2 inch long, 1/8 inch wide, and are bronze, golden, or reddish green with darker metallic green wings. The underside is metallic purple-red. The adults can usually be seen from June to August. The larvae are 1 to 1.2 inches long and are white or cream colored.  The larvae make S shaped galleries under the bark of the ash tree. The larvae and galleries can usually be seen year-round.  Once the tree is infested and the emerald ash borer population builds, the leaves begin to wilt and branches die leaving a sparse canopy. D shaped holes, which are 1/8 inch in wide and can be seen year-round, may be noticeable in the branch and trunk where the adult beetles emerged. Early detection is very difficult as it takes 1-3 years of infestation before an ash tree begins to show signs of mortality or decline. Tree mortality is caused when larval feeds on the tissue between the sapwood and the bark thus disrupting the transportation of nutrients and water.  This disruption eventually causes the branches to die first followed by the entire tree.

What Do We Do To Save Our Ashes?

Our Ash trees can be protected, but how? Removing a tree is costly, environmentally and financially. But there are options to save a tree. The safest, most efficient way to protect trees against the EAB is by utilizing a preventative insecticide injected directly into the tree.  This delivers the material exactly where it needs to be applied: in the tree.  As the EAB larvae or adult attempts to feed on the tree, it consumes tree tissue as well as the material designed to control it.  Because the material is injected directly into the tree, there is very little risk of exposure.  Though treatments are recommended to be done yearly, the material can provide up to two years of control against the emerald ash borer.  Our arborist works directly with a licensed pesticide applicator to ensure the most amount of protection possible against the EAB.

Do you have an ash tree? Contact us to discuss treatment options to protect your biggest investment!

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