Summer is often full of plans, but no one has been busier this year than the emerald ash borer. Although small, this invasive beetle is killing countless ash trees across the state. Since May, it has been confirmed in 11 additional counties in North Carolina, bringing the statewide total to 48 as of mid-July.
Newly-infested counties include (in order of confirmation): Polk, Rowan, Lenoir, Chatham, Davie, Caldwell, Nash, McDowell, Burke, Watauga and Yadkin.
Prior to 2019, the emerald ash borer was previously detected in 37 counties, including Jackson.
Emerald ash borer is a death sentence for ash trees unless they are protected with an insecticide. For landscape and ornamental trees, there are many options available to protect or save lightly infested trees, with professionally-applied emamectin benzoate and do-it-yourself applications of imidacloprid being the most popular.
An infested tree will exhibit general decline in health. The canopy thins and whole branches die. In addition, there could be sprouts growing from the base of the tree, vertical splits in the bark or increased woodpecker activity. When any combination of these symptoms is noticed, a closer inspection for direct evidence of the beetle should occur. The most obvious sign of the beetle is the ¼-inch D-shaped exit holes in the bark, caused when the adult beetle emerges from the tree. Upon removing the bark from the tree, winding, S-shaped larval galleries can be seen.
This year’s range explosion is second only to 2015, when 14 new counties were declared positive for the beetle, prompting the entire state to be quarantined for the pest. This quarantine regulates the transportation of ash material and hardwood firewood to reduce the accidental movement of it from one place to another. Because this wood-boring pest can easily hide within wood, not only will the quarantine help reduce its spread, but North Carolinians are encouraged to burn firewood within 50 miles of where it is cut.
The N.C Forest Service’s emerald ash borer range map is regularly updated to provide the most up-to-date known whereabouts of this tree killer and help make the best treatment decision for ash trees. If you suspect you have emerald ash borer in an uninfested county, contact your N.C. Forest Service county ranger or your county extension agent.