Scientific name: Agrilus planipennis

What Is It?

The emerald ash borer is a small Asian, wood-boring beetle that may attack and kill ash trees. The larvae burrow under the tree’s bark and eat the sapwood. These damaged layers of tissue below the bark are critical to transporting water and nutrients throughout the tree. Once damaged, the layers can’t transport water and nutrients causing the leaves and tree to die gradually.

Is It Here Yet?

No. They are established elsewhere in North America. This invasive insect was recently detected in Oregon and British Columbia.

Why Should I Care?

The emerald ash borer has killed hundreds of millions of ash trees in North America and gradually is moving westward all the time. It could devastate Washington’s forests and sensitive riparian areas. In addition, the potential costs of lengthy quarantines or replacing countless dead trees after an could be hefty.

How Can We Stop It?

Emerald ash borers may be transported in wooden materials such as shipping pallets, logs, and firewood. If you are outside of Washington, never bring back items capable of containing this pest from emerald ash borer quarantine areas, and do not transport wood, including firewood for camping, from the area where it was harvested. Instead, buy firewood when you get to your camping destination.

What Are Its Characteristics?

  • Adults are a jewel-like metallic green.
  • Elongated narrow shape, about a half-inch long
  • Woodpeckers eat emerald ash borer larvae, so heavy woodpecker damage on an ash tree is a possible sign of infestation.
  • When the new adult emerges from the tree trunk in the spring, it leaves a D-shaped exit hole that is rounder on one side and flatter on the other.

Additional Photographs