A killer who may lurk in your firewood: Stopping the spread of the emerald ash borer

Emerald Ash Borer

SLIGO NATURALIST — Without a doubt, the marmorated stink bugs will get a lot of media coverage this fall – and rightly so, since those ugly insects have caused a huge nuisance to homeowners and millions of dollars in crop damage for farmers all over the region.  But as everyone watches them hit in plague-like proportions, there’s another, more colorful invasive exotic bug out there that could be just as dangerous which needs our attention.  The Emerald Ash Borers (or EABs) are spreading across the Eastern United States in alarming numbers, and although they don’t give off an offensive odor or set up housekeeping in people’s closets and attics, they have the potential to change the landscape around us quite dramatically — unless someone discovers a way to effectively control them.

Unlike the stink bugs, EABs are beautiful creatures.  As their name implies, they sport a metallic green color that is almost breathtaking.  When they land, those shiny, green wings fold together in a perfectly dainty fashion that recalls a ballerina folding its arms after an arabesque.  They are silent, and when you first see them they seem harmless.

Emerald Ash Borer

Their destructive force actually comes in the form of their food preference.  They love to eat ash trees, and their appetite is unabated.

Although most people would struggle to identify the leaves of these important and common native trees, they have likely admired their fantastic color in the fall, which has been described as yellowish with an overlay of burgundy or purple.  In fact, ash trees are the most common trees in Baltimore City and are often found along streambeds here in urban areas of D.C. They thrive in busy parks.

Anyone who likes baseball may also share affection for these trees, since some of the most loved bats in the world are made from their wood, including the famous Louisville Slugger brand.  More recently, musicians who play guitar have come to admire the wood’s strength, beauty and resilience.  That same tough character has also led to an increase in use of ash in hardwood flooring.

In many of the forests of the U.S., however, ash trees are not so resilient anymore.  The Department of Agriculture says that the EABs have killed tens of millions of trees since the beetle was discovered in Michigan in 2002, and those numbers are expected to grow dramatically over the next decade.

As with many invasive exotics, these insects were most likely imported accidentally inside the shipping material of a package from their native continent, Asia.  Since their arrival, they have spread across dozens of states and through millions of acres of wooded land.  Although some predators here will eat them, their growth rate far exceeds the rate of current predation.

But experts say that the beetle doesn’t travel far on its own.  It is more likely to be the silent hitchhiker on a cord of wood or bundle of kindling thrown into the back of a truck.

To help control its spread, biologists are asking the public for help.  There are three key things people can do.

 1. Don’t move firewood.

If you go camping, buy wood as close to the camp site as possible or forage near to your location where and when allowed.  Don’t transport wood in your car, even from one county to another.  (Locally, sections of Prince Georges’ County have already been quarantined due to infestation, so the threat here is very real.)

 2. If you buy firewood for your home please buy a stock which has been kiln dried.

The heating process helps to kill the beetle’s larvae.

3. If you see or suspect damage, report it immediately.

Call the University of Maryland’s Home and Garden Information Center at 1-800-342-2507 and/or the state plant health director at 410-631-0073.

You don’t have to be a biologist to spot the damage.  One sign, biologists say, is woodpeckers foraging in large numbers on ash trees.  Another sure sign comes in the spring, when the borers emerge from the bark of trees and leave behind small D-shaped openings.  Affected trees usually die within three years of infestation.

To identify infested areas and control further spread of the insects, officials from the Maryland Department of Agriculture have been carefully monitoring wooded areas, including some sections of Wheaton Regional Park.  You might have noticed their monitoring devices, which look like purple kites stuck high in the trees.  These prism-shaped, cardboard traps are coated with a sticky material on the inside and are designed to attract and trap the EABs but are harmless to other types of wildlife, pets and humans.

To learn more about this pest you can visit any number of informative websites, includingstopthebeetle.info.

About the Author

Alison Gillespie
Alison Gillespie is the Sligo Naturalist. She writes about environmental and gardening issues here and on her blog whereyouareplanted.blogspot.com.