As of 2018, there was no reported EAB evidence in Highlands Ranch, Centennial, or suburban South Denver.
You may have read this story in the Denver Post on Monday, September 9th about the City of Denver shifting its forestry management from planting trees to managing and maintaining the 2.2 million trees in Denver’s urban forest. The part of the story about emerald ash borer (EAB) has generated quite a few phone calls here so we wanted to give a brief status about ash trees and EAB in Highlands Ranch.
Emerald ash borer is not currently in Colorado including Highlands Ranch. There, that was short, wasn’t it?
However, we have spilled plenty of ink about it over the past couple of years if you want to know more.
We have written generally about emerald ash borer.
More specifically what Colorado is doing to prepare.
What 6 common EAB symptoms are.
And most confusingly to your average person, about the ash borer that is here and is a threat to Colorado ash trees. To be doubly clear, the clear winged ash borer is an active pest of Colorado ash trees while EAB is projected to be in the area.
So why so much fuss about EAB even though it isn’t here yet? Why is the City of Denver pro-actively shifting funds to manage its urban forest in preparation for EAB?
There is a sense of the inevitable that EAB will be here soon. Having been found in eastern Kansas last year, the rapid spread generally since its discovery in Michigan in 2002, and the amount of transportation that goes through Colorado specifically have city officials and arborists forecasting EAB to arrive sooner rather than later.
Most commonly transported by firewood, EAB has been spreading across the upper Mid-West and Plains states over the past decade. More importantly, it has killed nearly every ash tree once it enters an area. About 15 percent of Denver’s trees are ash.
In fact, EAB’s potential devastation makes dutch elm disease look like a minor issue according to the Post story. So while EAB hasn’t made it to Highlands Ranch, it is likely a bad bet to plant any new ash trees in your yard. We will have a preventive spray/injection for high-profile ash trees that you absolutely want to save from EAB.
But the cost may prohibit widespread adoption.