Naturalist Journal: Emerald Ash Borer Hits PA

The emerald ash borer has been found in western Pennsylvania recently. Scientists and forest officials fear the pest will continue to move eastward, destroying Ash trees. Naturalist Dr. Chuck Welsh talks with host Matthew Craig about the beetle's potential ecological and ecomonic impacts for Pennsylvania.

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MATTHEW CRAIG: Out here at Beechwood farms where there are many kinds of trees, but today we are interested in Ash trees because of a pest called the Emerald Ash Borer. What exactly is it.

CHUCK WELSH: The borer is the larval stage of a little metallic green beetle about the size and shape of another familiar beetle called the firefly, or lightening bug.

MATTHEW CRAIG: So whatís the fuss about these little creatures?

Well as the name implies they bore into trees, Ash trees in particular. The adult females lay eggs in the trees and then the larval stage eats the tree.

MATTHEW CRAIG: Where did they come from?

CHUCK WELSH: They are indigenous to Asia and probably got here in packing crates on the west coast. The insect is making it way from the west and has just been found in Allegheny and Butler counties here Pennsylvania back in June.

MATTHEW CRAIG: Many animals graze on plants and it never makes the news, so these insects must really harm the trees?

CHUCK WELSH: Well itís not just like eating the fruit or a few leaves, they eat the important part of the plant between the bark and wood called the cambium. This will usually kill a few branches in the first year and then the entire tree parishes in about 2-3 years.

MATTHEW CRAIG: What are the signs that a tree has been infected?

CHUCK WELSH: The leaves will turn yellow in the middle of summer when they still should be green. If you know what to look for you can also see little holes in the bark of the tree shaped like upside down letter D.

MATTHEW CRAIG: Other than diminishing the wild populations of these trees are there broader ecological concerns?

CHUCK WELSH: Yes. Ash trees can grow to well over 100 feet tall and live several hundred years. Therefore, wild populations that are not harvested for economic reasons are integral parts of old growth forests. Loss of these trees will disrupt the ecological balance between other plants and trees and some species of birds like crows depend upon the tallest trees in the forest for nesting.

MATTHEW CRAIG: You mentioned harvesting, what economic value do Ash trees have?

CHUCK WELSH: The wood is light-weight but very strong and somewhat elastic. Therefore, it can be used for ìhitting and poundingî things. It is used for handles of hammers, hockey sticks, and especially for baseball bats. The homerun record of 755 set by Hank Aaron was accomplished using ash bats.

MATTHEW CRAIG: Does this effect Pennsylvania?

CHUCK WELSH: Yes it does because there are large tracts of ash in Pennsylvania and New York that are harvested for the baseball bat industry.

MATTHEW CRAIG: Do you have any thoughts on how the spread of this beetle might be controlled?

CHUCK WELSH: Research is going to have to be focused on which part of the life cycle presents the most physically feasible and most financially viable option. Obviously, there will be some kind of insecticide developed to at least slow its progress, even if cannot be eradicated.

MATTHEW CRAIG: Please keep us posted.


MATTHEW CRAIG: So do you have any recordings?

CHUCK WELSH: Yes. Crows in a huge ash tree.


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