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Boulder Creek, EAB, infested, ash tree, emerald ash borer

172 EAB-infested ash trees to be removed along Boulder Creek

BOULDER, Colo. — One of the most iconic paths in Boulder, Colo. is about to lose one of its greatest features: a vast amount of the trees that shade it from the summer sun.

The City of Boulder Forestry Division announced in June that it would be removing 172 trees along the Boulder Creek Path beginning June 18 and continuing through September. The trees slated to be removed are ash trees that are either dead or dying after having been infested by emerald ash borer (EAB), the most destructive forest pest in U.S. history.

The majority of the ash trees scheduled to be removed along the Boulder Creek Path are under seven inches in diameter, and are located between the 9th and 30th streets. The path itself is about five miles long, and the area where the trees will be removed represents nearly a two-mile stretch of it.

The primary reason for the tree removal, according to the City of Boulder Forestry Division, is to mitigate safety issues caused by the potential for falling limbs from dead and dying ash trees affected by EAB. This move comes just a year after 121 trees were removed from the University of Colorado campus in Boulder for the same reason.

An invasive pest, EAB has killed hundreds of millions of ash trees in more than 30 states and parts of Canada. The first Colorado discovery of the pest was recorded in Boulder in 2013. Since then, EAB has also been discovered in LongmontLafayetteLyons and Gunbarrel — and it was discovered in Superior just last month.

Long story short, “all public and private ash trees in Boulder are currently at risk,” the City of Boulder Forestry Division wrote in the press release on the Boulder Creek Path tree removal.

“Declining public and private ash trees will require removal before they present an unacceptable level of risk to public safety,” the City of Boulder Forestry Division continued.

While EAB has not yet been discovered in Denver, it’s only a matter of time before it arrives and poses the same threat to the 330,000 ash trees in Denver and the 1.45 million ash trees in the Metro area. But who wants to be a Debbie Downer when you can Be A Smart Ash? Below are some tips and tricks offered right here on this very website for residents in and around Denver worried about whether they may have an ash tree.

EAB tips for Denver & Front Range Residents:

  • Determine now if you have any ash trees: Identifying features of ash trees include compound leaves with 5 to 9 leaflets; leaflets, buds and branches growing directly opposite from one another; and diamond-shaped bark ridges on mature trees. Denver residents can also visit the Be A Smart Ash interactive map to see if they have an ash tree on or around their property. You can also help Denver map its urban canopy population by tagging your own tree on the Curio app.
  • If you have an ash tree, start planning: Decide if the overall health of the tree merits current or future treatment or if it would be best to remove and replace it with a different species. If you aren’t sure, contact a certified arborist. Denver residents can find a list of Smart Ash Certified tree treatment professionals specially equipped to administer EAB treatment plans. If you’re interested in exploring your treatment options, spend some time with The Smart Ash! He’s our very own arborist superhero teaching Denver residents how to fight EAB through four specific treatment methods.
  • Recognize signs of EAB infestation: Property owners with ash trees should be on the lookout for thinning of leaves in the upper tree canopy, 1/8-inch D-shaped holes on the bark and vertical bark splitting with winding S-shaped tunnels underneath. Report suspect trees by calling the Denver City Forester’s office at 720-913-0651 or by filling out this EAB Report Form.
  • Be aware of EAB imposters: Other insects like lilac/ash borer, ash bark beetle and flat-headed apple tree borer may look like EAB or cause similar tree symptoms.
  • Help prevent further spread of EAB: Do not transport ash or any hardwood firewood, or any other untreated ash wood products, to other locations. Boulder County and some surrounding areas are under an EAB quarantine, which may mean fines for those who move untreated wood from the area.