2017-08-02 / Columns

Emerald Ash Borer Happenings

IN THE WILD
by Dan Stiles Wildlife Biologist

We had many hundreds of white ash trees on our property in Morgan County. A few of them were monster trees, and two men, maybe three, with long arms could not possibly get their arms all the way around their trunks. They are all dead now, and most are still standing. But now, especially when the wind blows, more and more branches are falling to the ground.

I doubt there are any white ash trees left in Morgan County. I could be wrong. Maybe just a few isolated ones. The exotic Emerald Ash borer “takes no prisoners.” These borers from Asia showed up in our country in 2002. They arrived in Fayette County in 2007, and in Morgan County two years later. The efficient way these borers ripped through all my trees, it is a wonder to me that a few West Virginia counties were spared until this year (Tucker and Pocahontas). Randolph County, kind of in the middle of West Virginia, has yet to have a report of an Emerald Ash borer infestation. I’ll bet they will soon. This is awful business! No more ash trees in our state?

Emerald Ash borer’s larvae feed on the cambion layer (the living part of the tree) between the outer bark and the sapwood thereby interrupting the flow of nutrients and water from the roots to the leaves, and the tree dies. If you remove the bark on an infested tree you will see the hundreds of what are called serpentine galleries that in effect girdle the tree hundreds of times. To kill an undesirable tree, cutting the entire circumferences at its base with a chainsaw only one time will also interrupt the flow of nutrients and water, and kill a tree similarly.

Emerald Ash borers destroyed all my ash trees in three years. These beetles can fly about a half mile to settle on uninfected ash trees where they lay their eggs, and the cycle is repeated. Trouble is, what if all the ash trees in the vicinity have already been killed by beetles that found the trees earlier? Ash trees are the only tree species these beetle’s larvae feed upon. It seems to me the wave of invading beetles would starve to death when this happens.

So, I asked Dr. Crutchfield, West Virginia’s plant/pest biologist for the Plant Industries Division, WV Department of Agriculture. He replied, “I don’t think anyone knows for sure. It is likely the beetle population will crash as the last “older” ash trees are killed. However, ash are prolific seeders and seedlings are likely to develop. If the beetles “hang around” in small numbers, they could potentially infest these seedlings. There may be fluctuations between beetle and ash numbers for years to come. In addition, there is always the chance of resistant trees, beetle parasites, or disease, etc. that may influence this cycle.”

I have noticed a very few ash seedlings scattered about on my property that I’ll need to mark with scarlet colored tape, so I’ll remember to give them every advantage over any competing vegetation. I guess there is hope for ash tree seedlings, if the beetles don’t find them.

As you drive along the highway, you will be bound to see dead standing leafless ash trees. If you look closely at them, you can confirm their species, because all the branches are exactly opposite one another.

Imagine. Just eight years ago, Emerald Ash borers were first reported in Morgan County. Today, almost all our ash trees are dead along with billions of others in the United States and Canada. It’s a silent, subtle, tragic, environmental catastrophe!

If you have a live ash tree on your property, I suggest you water it, if it’s dry, and fertilize it periodically. I think living ash trees are treasures these days!

Return to top