Ash Borers Still Active

We love and value trees, and work tirelessly to save as many as we can from the environmental stressors, fungi and pests that can weaken and kill them. Since 2007, Tree Green has been doing just that for our region’s Ash population, and we can proudly say that 94% of the Ash trees we have treated for the Emerald Ash Borer are alive and doing very well! Back in 2007, the forecast was that we’d be just about finished with the ash borer in our area. We’ve obtained new data showing that the ash borers are still very active, however, requiring continued treatments to prevent damage. Owners of ash trees need to be diligent about treatments until the ash borer has completely cycled through all trees in our area. Two annual treatments continue to be necessary to effectively fight the onslaught of this killing pest.

As you may know, the Ash Borer first attacked trees in Michigan. Experts there found that progression of the beetle took 3 to 5 years to affect all ash trees. Owners of ash trees were told that aggressive treatment should continue for roughly that long, after which treatment could be reduced to approximately one treatment per year.

However, we have come to find that the progression of the beetle in Illinois is not following what experts saw in Michigan. We are, therefore, in uncharted territory and honestly just don’t know when all the untreated Ash trees within an 8 to 10 mile radius of your home will be gone.

Why isn’t the progression the same? We have two theories.

  • First, Illinois has far more Ash trees in a much tighter geographical area than were in Michigan. It is said that Ash trees account for nearly 1/3 of some towns’ overall tree canopy in our region. With so many more trees for the borers to choose from, it may be that fewer are getting into each individual tree, resulting in a longer time frame for them to do enough damage to kill an individual tree.
  • Second, when the Ash Borer attacked Michigan, the insects were able to multiply ‘unabated’, because by the time Arborists discovered an effective treatment plan for them, it was too late. Nearly all of Michigan’s Ash population was already gone. Here in Illinois, however, homeowners, city Arborists and other companies were able to use the proper treatment programs developed in Michigan and began treating Ash trees right away. Trillions of potential borers were killed due to this treatment and, unlike Michigan, did not run unabated. Because of this, it is likely that fewer borers are available to attack non-treated trees.

We at True Green believe that the benefit of continuing to treat these valuable trees outweighs the cost of the treatment. Just as we pay for insurance to protect our houses, cars, health and lives, our valuable trees fall into a similar category. It is a proven fact that healthy, mature landscaping can add 15% to your property value. The shade and wildlife habitat your trees supply, and the overall pleasure of looking at them, is invaluable. It makes sense to protect them. Call us at 630.668.4350 to get started on an effective treatment program for you Ash trees.

Did the cold winter kill the Emerald Ash Borer?

You may have seen or read discussion that the prolonged, extreme cold caused by the polar vortex this winter might eliminate the Emerald Ash Borer (EAB).  This, unfortunately, is not true. The cold may have killed off some of the population, but it did not eliminate it.

Dr. Deborah McCullough, a Forestry & Entomology professor at Michigan State University (Michigan is where the EAB first appeared in the U.S.), has recently written that EAB will survive the cold. “In the fall, as temperatures begin to fall, physiological changes occur in insects including EAB. Insects are able to produce an internal antifreeze that prevents their cells from freezing.”

In addition, a representative from the Chicago Botanical Garden was featured on WGN television in the first week of April. They said the same thing, and went so far as to remove the bark from area Ash trees while on air, and found the larvae alive and well inside those trees.