Emerald ash borer now detected in more than 20 Front Range cities
October 21, 2025
First detected in Boulder in 2013, this invasive, tree-killing beetle threatens thousands of Colorado’s ash trees.
EAB Resources
Publications
- EAB Quick Guide (6 MB PDF)
- Managing EAB: Decision Guide (630 KB PDF)
- Insecticide Options for Protecting Ash Trees from Emerald Ash Borer (7.5 MB PDF)
- Diagnosing Emerald Ash Borer and Other Ash Tree Damage: A Diagnostic Field Guide (5.6 MB PDF)
- Insecticides Used to Control Emerald Ash Borer on Residential Shade Trees (900 KB PDF)
Partner Websites
- Don’t Move Firewood
- Find an Arborist to Inspect your Ash Tree
- Emerald Ash Borer Information Network from Michigan State University & USDA Forest Service
CSFS Links
CSFS News Releases
Emerald Ash Borer Confirmed on Colorado’s Western Slope for First Time
July 6, 2023
In June 2023, experts from Colorado State University confirmed the presence of emerald ash borer (EAB) in two new towns in Colorado: Carbondale and Littleton.
Emerald Ash Borer Confirmed in Thornton, CO
June 28, 2022
Experts from Colorado State University Extension confirmed the presence of emerald ash borer (EAB) in the City of Thornton in June 2022. This is the first confirmation of EAB in a Colorado city east of I-25.
Green Menace Has Spread to Erie
July 13, 2021
The Town of Erie is the latest community on the Front Range to confirm the presence of emerald ash borer – an invasive, highly destructive tree pest.
Emerald Ash Borer on the Move Along Front Range
May 25, 2021
EAB is on the move along the Front Range, and with Emerald Ash Borer Awareness Week taking place this week, partners with the Colorado Emerald Ash Borer Response Team are encouraging residents to prepare for EAB and ‘plant ahead’ for the inevitable.
Assess Trees in Spring to Prepare for Emerald Ash Borer
April 13, 2020
BROOMFIELD, Colo. – With a new spring season, trees are emerging from their winter dormancy period across Colorado to bring life, color and vibrancy to our urban forests.