Emerald Ash Borer
![[photo:] Adult Emerald Ash Borer - underside view](/peth04/20041015200145im_/http://ncrs.fs.fed.us/4501/eab/local-resources/images/eabadultbellytrans.gif)
North Central Research Station entomologists working in East
Lansing, Michigan, provide basic information on the biology and ecology of
exotic forest insects so managers can formulate proper management strategies.
Over the years, our work has influenced development of policy and regulations to
control various pests on regional, national, and international scales. We are
currently helping combat an outbreak of the emerald ash borer, a new exotic pest
to North America.
Issue
The emerald ash borer, Agrilus planipennis (Coleoptera:
Buprestidae), was
discovered infesting and killing thousands of ash trees (Fraxinus
spp.) in southeastern Michigan in July
2002. Evidence now found suggests that A. planipennis
first entered Michigan at least 5 to 10 years ago,
presumably from solid wood packing materials or dunnage used to transport
manufactured goods.
In addition to Michigan, EAB was also found in Ontario in 2002, and in Maryland
and Ohio in 2003.
Michigan and Ohio have imposed state
quarantines on movement of ash trees and ash wood products to
limit human-assisted spread of this pest. The USDA
Animal and Plant Health Inspection Service and the Canadian
Food Inspection Agency have imposed Federal quarantines.
Potential Impact
![[photo:] House in suburban Detroit with dead ash in background, ash death is attributed to emerald ash borer.](/peth04/20041015200145im_/http://ncrs.fs.fed.us/4501/eab/local-resources/images/housewdeadashbehind.jpg) ![](/peth04/20041015200145im_/http://ncrs.fs.fed.us/4501/eab/local-resources/images/spacer-h116.gif)
In Michigan, this borer has been
observed only on ash trees. It has killed green ash (F.
pennsylvanica) , white ash (F. americana), and black
ash (F. nigra). The trees die when burrowing larvae
girdle the conducting tissues along the main trunk. Many trees
seem to lose about 30 to 50% of the canopy after the first year
of attack and the entire tree is often killed after 2-3 years of
infestation. Stress likely contributes to vulnerability.
However, relatively vigorous trees have also been killed by this
exotic species.
Ash occurs extensively in the natural and
urban forests of the Eastern United States. In 2001, ash
accounted for more than 149 million cubic feet of timber
products nationwide. It is estimated that there are more
than a billion ash trees in the United States, of which about
800 million occur in Michigan. Ash is planted extensively in cities and
towns as a hardy urban shade tree. The quarantines restrict
movement of ash logs, lumber, firewood, and nursery stock. |