Emerald ash borer infestation pending for Rowan County
Published 12:00 am Friday, June 10, 2016
SALISBURY – Emerald ash borer (EAB) infestations have been confirmed in several locations just to the north of Rowan County.
EAB is a metallic-green beetle that bores into ash trees and feeds on tissues beneath the bark, ultimately killing the tree.
Newly detected infestation in trees in several locations in Davidson County appear to have been present for a considerable length of time. Unfortunately, it’s difficult to detect an infestation until the trees are in noticeable decline. It is very likely that there are trees in Rowan County that are already infested with the pest.
Affected ash trees exhibit the following symptoms of EAB: thinning and dying crowns; increased woodpecker activity that causes the tree to look like it is losing patches of bark; small, 1/8-inch D-shaped exit holes where adult beetles emerged from the trees; observable galleries on the inside of the bark; and cream-colored larvae.
The signs aren’t always immediately noticeable as adult beetles lay eggs on the bark of ash trees. When the eggs hatch, the larvae or immature beetles bore into the bark and feed on tree tissues underneath. This disrupts the movement of nutrients and water within the tree and eventually kills the tree.
Widespread detection in N.C. led to quarantine in 2015
The emerald ash borer is a non-native invasive insect from Asia that was first found in the U.S. near Detroit in 2002. It has already killed tens of millions of ash trees in the U.S. Host plants include all native ash trees as well as white fringetree.
In North Carolina, the beetle has been discovered in Buncombe, Catawba, Davidson, Durham, Franklin, Graham, Granville, Guilford, Iredell, Johnston, Lincoln, Madison, Orange, Person, Vance, Wake, Warren, Wayne and Wilson counties.
Because of its extensive and scattered range, the entire state was quarantined for this pest last year. The quarantine prohibits the movement of ash material (all plant parts), the insect itself, ash nursery stock and all hardwood firewood into non-quarantined areas, such as South Carolina or central Tennessee.
Movement of firewood can spread beetle
EAB can spread naturally by flying to new host trees upon emergence, but this is limited to a few miles a year. The more threatening spread is long-distance movement, which can easily occur when a beetle is accidentally transported from an infested area to an un-infested area through infested ash wood products by humans.
The spread of EAB to Tennessee and Virginia, including detection sites in counties adjacent to North Carolina, is believed to have been accidentally facilitated by humans, likely while moving firewood, Bost said. Though moving firewood within the state is legal, it is strongly recommended that people burn local or treated firewood to reduce the spread of not just EAB, but many invasive pests.
Adult EAB beetles are a metallic-green color, about 1/2 inch long and 1/8 inch wide. If their wing covers are pried up, their bodies underneath are a metallic purplish-red color. In North Carolina, the adult EAB is expected to be active in the late spring, likely April through June. EAB larvae may be found under the bark of an infested tree most of the year.
For more information about EAB and control options, visit ncforestservice.gov and follow the links under the “Forest Health” section. To view current federal EAB quarantines, visit the national EAB website, www.emeraldashborer.info.
The N.C. Forest Service continues to monitor the spread of this pest. People who suspect or find an EAB-infested tree in a new area should contact the N.C. Department of Agriculture and Consumer Services at 1-800-206-9333 or email@example.com. The Rowan county ranger’s office can be contacted at 704-216-8993.