Emerald Ash Borer Killing Ash Trees

Ash trees in Iowa and many other states in the United States are being killed by emerald ash borers. The borers consume the connective tissue between the wood and the bark. Notice that the underside of the bark has very interesting patterns where the borer consumes the tissue. They are an invasive species in Iowa and many other states. Some invasive species like the borer kill their host in a parasitic symbiotic relationship.

• What could do this to an ash tree?

• What kind of symbiotic relationship do emerald ash borers have with ash trees?
• How could one little bug (emerald ash borer) change an ash tree?

Students could:

• Use the related websites to investigate other invasive species with symbiotic relationships. This could be a good phenomenon to look at on a day or two basis in the middle of an ecology unit. 
• Explore how the introduction of an outside species to a new environment can change the environment permanently. 
• Research how these ash trees are being turned into “zombies” -- as the borer consumes the connective tissues it damages the trees ability to move water and nutrients to the top of the tree so they die from top down.

• US Department of Agriculture (USDA) | National Invasive Species Info: Emerald Ash Borer General information about the emerald ash borer.
• American Forests | A Threatening Insect Infestation: This article describes the symbiotic relationship between insects and trees and how the borer is different.
• Iowa Department Of Natural Resources (DNR) | Emerald Ash Borer: Overview of the emerald ash borer from the Iowa DNR. 
• The Dirt Doctors | Ash Trees: All You Need to Know How to identify different types of ash trees.