What is Emerald Ash Borer?

Emerald Ash BorerEmerald ash borer (EAB), Agrilus planipennis, is an exotic beetle from Asia that attacks ash trees. The EAB has killed over 60 million ash trees since it was first discovered in southeastern Michigan near Detroit in the summer of 2002. The adult beetles eat the ash foliage and the larvae feed on the inner bark of ash trees. The larvae prohibit the tree’s ability to transport water and nutrients, which kills the tree. The Emerald Ash Borer is native to Asia and was likely transported in wood packing material to the United States.

Emerald Ash Borer larvae do the most damage from August to October– stop them in their tracks with fall treatments! Don’t wait until spring.

Where is Emerald Ash Borer?

EAB is found in 20 states and 2 provinces– click here to see if your state is affected and may be under a quarantine prohibiting the movement of firewood and ash stock between states.

Do I have an Ash Tree?

Ash trees can be identified by looking at their leaves and bark. White Ash and Green Ash are two common species found in the Midwest United States. Mountain Ash is not attacked by Emerald Ash Borer.

  • Leaves – Oppositely arranged on twig, pinnately compound (several leaflets make up a leaf), and has 5 – 9 dark green leaflets
  • Leaflets – Either very short stocks or no stocks attached to the leaf stem; smooth or sometimes finely serrated (saw–toothed) on the upper half
  • Fall Color – White Ash – red and purple, Green Ash – yellow and orange
  • Bark – Young bark is usually flaky, light-gray to gray-brown in color, interlacing ridges and deep furrows forming diamond-shaped areas

Is My Ash Tree Infested?

Just because you can’t see Emerald Ash Borer doesn’t mean it isn’t there. Larvae do the most damage from August to October, so treat your ash trees proactively before you see symptoms.

Image courtesy of Univ. of Illinois Extension
Image courtesy of Univ. of Illinois Extension.

Canopy die-back on the top third of the ash tree

Epicormic sprouting

Young sprouts cluster at the base of the ash tree

Image courtesy of Purdue University Extension
Image courtesy of Purdue University Extension.

Vertical splits in the bark

Image courtesy of Purdue University Extension
Image courtesy of Purdue University Extension.

Small, distinct D-shaped exit holes in the bark

EAB Troy MI 011

If the bark peels, serpentine S-shaped tunnels under the bark on the surface of the wood

If your ash tree has any of these symptoms and less than 40% canopy loss, TREE-äge Insecticide treatment is still likely to be effective. Contact a Service Provider and ask for TREE-äge Insecticide.