Boring Beetles

This Spring, I will be adding posts from guest bloggers. This post is by badellin.

Have you ever been sitting in traffic and seen a bumper sticker on a car that says,

Don’t move firewood, it BUGS me!?

I had seen quite a few of these stickers and decided to find out what the hype was all about.  This bumper sticker is about a large epidemic affecting trees in North America.  This isn’t a new concept to us, as in the past we have dealt with tree epidemics such as Dutch Elm Disease and the Chestnut Blight.  However, this current epidemic that everyone is talking about on the bumpers of their cars isn’t caused by a fungus but an insect.  This insect is an emerald ash borer.

The emerald ash borer, Agrilus planipennis, is an invasive beetle species in North America.  This beetle originates from Asia- Eastern Russia, Northern China, Japan, and Korea. The emerald ash borer arrived in North America in ash tree wood transported from these originating countries to North America.  Once the emerald ash borer established in North America, it is being transferred from affected areas of the continent to unaffected areas of the continent by the same method.

Emerald ash borer eggs are laid on ash trees and the larvae begin boring through the ash trees and feeding on the cambium layer of the tree.  Once the larvae mature into adults they bore out of the tree.  It’s the internal boring and feeding of the larvae, though, that causes the damage and eventual death of the tree.  The tree will develop a callus tissue as a result of the boring larvae and in the end, after an infestation of emerald ash borers, the tree will eventually die.

A row of ash stumps along St Mary's Road on the Notre Dame Campus in South Bend, Indiana. Photo: WNDU.com

It is important for people to understand the magnitude of the impact of this invasive beetle species.  The emerald ash borer has already killed millions of ash trees and continues to kill more.  Containment is a major component of stopping this beetle.  A common transport mechanism for this beetle is firewood.  People and companies, among others, will move firewood from location to location and in turn they are moving the emerald ash borer to new locations for them to devour.  Therefore, it’s important to be aware of the wood that we’re moving around to ensure we aren’t harboring this invasive species.