Emerald Ash Borer (EAB)

The Emerald Ash Borer (EAB) is a highly destructive pest from Asia that arrived in the United States in 2002. It has been spreading across the Midwest, killing tens of millions of ash trees, and has made its way into St. Louis and St. Charles. Here is a quick list of important things to know about EAB:

  • EAB has already killed tens of millions of ash trees across the Northeast and Midwest
  • EAB primarily attacks ash trees
  • There is about a 15-year time frame from when EAB arrives and all unprotected ash trees are dead

Adult females eat the leaves of ash trees during the summer and lay their eggs on the bark. When the larvae hatch they chew through the bark and into the interior of the tree, damaging the vascular system. With the vascular system damaged, trees are unable to deliver nutrients and water to the top of the tree. Branches start to die off, and after 2 to 4 years the tree dies. Once EAB has arrived no trees are safe. Healthy trees are at just as much risk as weakened trees.

Ash trees can be treated with an injectable insecticide. Treatment is most effective when begun while a tree is still healthy. By the time people notice dead branches considerable damage has already been done to the vascular system. Treatment can prevent further damage to an infected tree, but cannot reverse damage that has already been done. Treatments must be done every two years to be effective, so careful consideration must be given to the cost and whether it is worthwhile. An arborist from Ray’s can help assess your ash trees and determine what options are available.

The following links offer more information on Emerald Ash Borer:

Emerald Ash Borer
Tree Injection