Emerald Ash Borer
What is emerald ash borer?
The emerald ash borer is an invasive wood boring beetle that is native to Asia. It was first discovered in North America in 2002 (in the U.S. in 2003).
Adults are metallic-green and grow up to one-half to one-inch long. Although adults cause little damage, the larvae kill ash trees within one-four years by feeding on the inner bark of the trees and preventing the transportation of nutrients. According to the Minnesota Department of Agriculture, an infestation can be identified by "one-eighth inch, D-shaped exit holes in ash tree bark and serpentine tunnels packed with sawdust under the bark."
Only "true" North American ash trees are susceptible to emerald ash borer. Green, white, black, blue, pumpkin, Marshall seedless, Autumn Purple and Summit are examples of true ash. Mountain ash, prickly ash and some others with "ash" in their name are not true ash trees and therefore are not susceptible.
More information can be found on the Minnesota Department of Agriculture's website.
Photo of emerald ash borer by Benny Moto is under a Creative Commons attribution license.
How is it treated?
True ash trees that are most at-risk are stressed and unhealthy. The best line of defense is to keep ash trees healthy by regularly watering them and fertilizing in spring or fall.
Tree care companies with insecticide application permits are offering treatments for ash trees. These treatments do not cure an infested tree. Rather, they stabilize the tree and prolong its life. Treatment efficacy is dependent upon various factors (e.g., life of the tree, overall health of the tree, degree of infestation) and treatment must continue for the life of the tree.
The trade off between these experimental treatments and the replacement of trees altogether should be considered by those faced with infested ash trees.
A list of providers can be found on the Minnesota Department of Agriculture's website. Be sure to consider only tree care companies with ISA certified arborists.
Why is this important to Tree Trust?
Since its introduction to the U.S. in 2003, the emerald ash borer has destroyed tens of millions of ash trees in our neighboring states. Just two weeks ago (mid-May 2009) an infestation was confirmed in St. Paul, Minnesota - less than one mile away from Tree Trust's administrative offices.
This threat to Minnesota's 900 million ash trees echoes the devastation caused by Dutch elm disease in the 1970s - the very crisis that led to the creation of Tree Trust.
In 1976, in response to the overwhelming loss of trees and the high unemployment rates Tree Trust was founded and began employing and training out-of-work individuals to reforest the Twin Cities. Since that time we have planting thousands of trees across the Twin Cities metro area, because trees are vital to the health and vitality of our communities.
How can I help?
As the threat of emerald ash borer loomed and reminded us of the overwhelming loss of trees to Dutch elm disease, we ramped up our efforts to reforest the Twin Cities by launching our Green Futures initiative in 2008.
Now emerald ash borer is here - in our own backyard.
Since treatment is costly and not a cure, we face the potential loss of 900 million trees throughout Minnesota.
Tree Trust’s Green Futures brings the community together and allows you to take an active role in combating the effects of emerald ash borer - planting tomorrow’s trees today.
Learn more about Green Futures...
Banner photo by James M. Phelps is under a Creative Commons attribution license.
Tree Trust
2231 Edgewood Ave. S.
St. Louis Park, MN 55426
Phone: 952.767.3880
Fax: 952.767.3650
