This past weekend I saw something a little peculiar on the outskirts of Louisville, Kentucky. It was a purple 3-sided box up in a tree next to a road. I just had to investigate. I had my camera with me so I took a photo of this odd thing. After an intense on-site audit of the purple prism, I noticed a sticky substance on all three sides and it was open in the middle where something in a small bag was hanging. Oh yeah, and the fact that bugs were attached to the sticky outside. I thought maybe it was an insect experiment of some sort. After further investigation I found out I was on the right track.
The purple boxes or prisms are baited with oil from the Manuka tree and are hung from ash trees. The “traps” are made to attract the Emerald Ash Borer (EAB), a nasty little insect responsible for killing millions of ash trees in North America. Even the color purple has been tested to attract the EAB more than other colors. The traps don’t bring more EABs to the area, they just draw any adult EABs present in the area. The amount of EABs found on the trap will help the USDA or state forestry offices be able to pinpoint the “leading edges” of existing infestations. A trap located in your community does not mean EAB is present; it means they are looking for the beetle.
The emerald ash borer, a small, metallic-green, wood-boring beetle, made its first public appearance in the United States in Michigan around 2002, having stowed away in wooden packing material from Asia roughly 10 years earlier. They have now been spotted in Illinois, Indiana, Kentucky, Maryland, Ohio, Pennsylvania and West Virginia. The insect is unusually difficult to kill and more than 7.5 billion ash trees are currently at risk.
Ash trees are the only host species for EAB. The lifecycle of EAB is dependent upon the ash tree; the adults feed on the leaves, lay eggs in its crevices, and the larvae develop under its bark. This slowly kills the ash tree. Evidence of the emerald ash borer sometimes takes up to a year to recognize. Some signs that the emerald ash borer has infested a tree are D–shaped holes in the bark of the trunk or branches and shoots growing from the base of the tree.
The insect samples collected from the traps will be cleaned and sent to a USDA identifier for verification. All verifications of EAB will be communicated to the appropriate State plant regulatory official. For more information, go to the USDA website on the Emerald Ash Borer. Let’s hope that this pest can be controlled and our ash trees can thrive again.