What Is Emerald Ash Borer?
Emerald ash borer (Agrilus planipennis) is an invasive beetle from Asia that kills ash trees — every species of ash, without exception. It was first detected in the United States in Michigan in 2002 and has since killed hundreds of millions of ash trees across North America.
EAB doesn't just weaken trees — it kills them. Once a tree is infested and untreated, it typically dies within 3–5 years. The infestation spreads from tree to tree through adult beetles and through the movement of ash wood and firewood.
Why Colorado Springs Homeowners Need to Act Now
Here's the situation as of 2026:
Front Range cities where EAB has been confirmed as of October 2025, including Boulder, Fort Collins, Longmont, Loveland, and Greeley.
Public trees in Colorado Springs is an ash tree — making this one of the most ash-dense cities on the Front Range.
Of ash trees in Colorado are now at risk. Denver alone has an estimated 180,000 street ash trees.
Time from initial infestation to tree death without treatment. Early detection and action are everything.
The beetle spreads primarily by flight — adults can travel several miles on their own. Once EAB is confirmed in Colorado Springs (which is a matter of when, not if), the window for effective treatment narrows quickly. Trees that were treatable before confirmation may be too heavily infested to save by the time homeowners act.
How to Identify an Ash Tree
Before you can protect your ash trees, you need to know if you have them. Ash trees are extremely common in Colorado Springs — planted extensively as street trees and yard trees throughout the 1980s and 90s.
Key Ash Tree Identification Features
Not sure if you have ash trees? Call us for a free assessment — we'll identify your trees and advise you on risk.
Signs of EAB Infestation
EAB is notoriously hard to detect in the early stages — the damage happens under the bark, invisible from outside. By the time visible symptoms appear, the infestation is already serious. Here's what to look for:
Early signs
- — Thinning canopy — sparse leaf coverage at the top of the tree
- — Epicormic sprouting — unusual shoots growing from the trunk or lower branches (the tree's stress response)
- — Increased woodpecker activity — woodpeckers drilling for EAB larvae create characteristic 'blonding' of the bark
Moderate infestation
- — S-shaped galleries visible if bark is peeled back — the feeding tunnels larvae carve under the bark
- — Bark splitting and cracking — the galleries disrupt the cambium, causing bark to crack and fall away
- — Crown dieback progressing from the top down — typically 25–50% canopy loss
Severe infestation
- — D-shaped exit holes — 1/8 inch, flat-bottomed holes where adult beetles emerge in late spring/early summer
- — More than 50% crown dieback — at this stage the tree may no longer be treatable
- — Bark sloughing off in large sections
Your Options: Treat or Remove?
Once EAB arrives in Colorado Springs, every ash tree owner will face a choice: treat preventively, treat after detection, or plan for removal. Here's how to think about it:
Treatment — When It Makes Sense
Insecticide treatment (soil injection or trunk injection) is highly effective when started before or in early infestation — generally when the tree still has 50%+ of its canopy. Treatment must be repeated every 1–2 years indefinitely while EAB remains in the area.
Removal — When It Makes Sense
Removal is the right call for trees that are too far gone to save, structurally compromised, in a poor location, or where treatment costs outweigh the tree's value. Dead or dying ash trees become brittle and unpredictable — early removal is far safer and cheaper than emergency removal.
Important: Don't wait for visible symptoms to decide. By the time you can see that a tree is struggling, it may already be past the treatment window. The best time to assess your ash trees is now — before EAB arrives in Colorado Springs.
What to Do Right Now
Identify your ash trees
Walk your property. If you have trees with opposite, compound leaves — especially if they look like the descriptions above — assume they're ash until confirmed otherwise.
Assess their health and location
Are they structurally sound? Are they in a spot where losing them would be a significant loss? Or are they crowding structures, in decline, or otherwise problematic?
Get a professional assessment
Before EAB arrives in Colorado Springs, have a qualified tree service evaluate your ash trees. We can give you an honest picture of each tree's condition and what your options are.
Make a plan
Decide now — treat or plan for removal. Trees you plan to keep need to be ready for treatment the moment EAB is confirmed locally. Trees you plan to remove are better done proactively, before they're dead.
The Cost of Waiting
When EAB kills an ash tree, that dead tree doesn't stop being a problem — it becomes a more urgent and more expensive one. Dead ash trees become structurally brittle faster than almost any other species. Within 1–2 years of death, they begin dropping large limbs unpredictably.
In Denver, where EAB arrived years earlier, the city is now dealing with tens of thousands of dead street ash trees — removal costs have surged because supply of tree crews is overwhelmed by demand. Colorado Springs homeowners who act proactively will have more options, better timing, and significantly lower costs than those who wait.
Have Ash Trees in Colorado Springs?
We'll walk your property, identify your ash trees, assess their condition, and give you an honest recommendation — treat or remove — with a written estimate. No charge, no pressure.