The invasive emerald ash borer can now be found in nearly half of Kentucky and it is spreading west. The University of Kentucky reports.
This is a group of ash trees in the University of Kentucky’s arboretum that have been treated for the emerald ash borer. The adult stage of the EAB is a small, dark green, metallic beetle the size of a quarter. The insect may be small, but the damage can be costly.
According to entomologist Jonathan Larson, “The way to think about it is, you are either going to pay a lot of money upfront, to have the tree removed, or you are going to pay that in installments over successive years to have the tree treated, but if you have an ash, you are going to have to spend some money on it.”
The ash tree is a valuable hardwood, used for everything from furniture to flooring, but once the EAB has attacked an ash tree, its only value is firewood.
“It will take out all of the ash trees,” Lyon County Extension agent Susan Fox states. “The blue ash is a little bit more resilient. It takes longer for the emerald ash borer to kill it. It is not its preferred species, but the blue ash will be taken out eventually. If they want to save the tree they better be thinking about watching it.”
Fox says that the EAB is now entering western Kentucky: “It is approaching our area. It’s in neighboring counties. It’s in Crittenden County and it is going to build gradually.”
She says that people should be on the lookout for thinning crowns of their ash trees with flaking bark revealing serpentine tunneling of the larvae and an inverted “D” shape exit hole, flat on one side and round on the other, where the adult exited the tree.
Jonathan Larson said that the spread of the emerald ash borer is a slow process.
“Their natural spread isn’t all that quick. You have to compare it to a cheetah and a slow-moving tortoise,” he adds. “The natural spread is like the tortoise, or we can sometimes move the wood around and get them to those new locations a lot quicker.”
Larson said that if you own ash trees be prepared to make some hard decisions on whether to remove the tree now and pay the money upfront or invest over the next ten years to treat the tree.