The Biggest Myths About Emerald Ash Borer in Chicagoland

By Jeff Palmer

Villages and cities throughout Illinois are becoming acquainted with a tiny insect that has thrown them into full-blown crisis mode. The Emerald Ash Borer (EAB) from Asia is so named because it bores into ash trees and compromises their circulatory system which results in death. Towns from the Galena, to Mount Prospect, to Plainfield have thousands of ash which will cost millions of dollars to remove and replace as EAB moves through. Below I tackle the biggest myths about EAB to help Illinois get ahead of this crisis with the latest facts:

EAB can be contained if we cut infected ash trees quickly

EAB is so prolific that it achieves near 100% infestation in a few short years whether you remove infested trees or not. Towns such as Ft. Wayne, Indiana, Akron, Ohio and Geneva, Illinois discovered EAB in their ash trees a few years ago and today almost every ash tree is infested. EAB moves too quickly to contain.

EAB cannot be treated

Leading EAB scientists published their synthesis of research which indicates infestations can be controlled when detected and treated at an early stage. Trees with more than 50 percent of their canopy are candidates for treatment. Cities such as Milwaukee, St. Paul, Chicago and Naperville aggressively treat ash trees with an extremely effective low dose insecticide which protects the tree for two years. (Note: the most effective treatment must be injected into a tree’s trunk by a licensed arborist.)

It’s less costly to cut than to treat

A parkway tree can be treated for 20 years or more at the same cost as cutting and removing. Loss of shade means higher summer energy bills. And, trees comprise 5-7% of a home’s value. For towns, losing hundreds or thousands of trees creates potential flooding problems because each mature tree holds thousands of gallons of water that will otherwise end up on the streets.

Our town is all over this, we can relax

Governments only look after trees on public land such as park ways, parks and schools. The vast majority of ash trees are planted on private property and an infected ash tree is a danger to property and people. The infestation in the northern half of Illinois has reached a level whereby it’s prudent to evaluate every ash tree (immediately) on both public and private land.

There’s a natural solution

There is but it can’t help with the current infestation. Tiny stingless wasps prey on EAB and are being bred and released.  Unfortunately, these wasps live only in wooded areas and take years to reach an effective population. Untreated trees will not survive the wait.

Once I start, treatment continues until the end of time

The most effective treatment option lasts 2 years with excellent results.  As EAB enters your community it will devastate all untreated ash within 7-10 years. When this happens, EAB population levels will crash for lack of food which means that treatment intervals can be expanded. It is also possible that science will find alternative methods for ash trees to survive EAB on their own.

Ok, I’m doomed

Only if you ignore the issue. The first step is to evaluate the EAB problem that affects your property. Consult an expert. There’s a pretty good chance that you can make a small investment this spring and avoid paying to have your ash trees cut down. And some towns and villages let homeowners treat parkway trees.

Below is a good resource to which the University of Illinois contributed to start your EAB education:

www.emeraldashborer.info/files/multistate_eab_insecticide_fact_sheet.pdf

Jeff Palmer is an ISA Certified Arborist with ArborJet and an expert on Emerald Ash Borer. He is currently training arborists throughout Illinois on how to treat infected trees.