Emerald Ash Borer in Denver Colorado; Restrictions for Dumpster Rental.

Updated 1/29/2020

Since the original publication of this article, the Emerald Ash Borer (EAB) was confirmed in the City and County of Broomfield as of August 2019, the first confirmation of EAB in Colorado outside of the federal quarantine that primarily encompasses Boulder County. As of that time, the ash borer has not yet been detected in Denver, though it could technically already be here.

Having said that, systems of defense have been in place over the years to prevent further infestation, such as through Denver Parks & Recreation’s Be A Smart Ash, as well as other partners. Tree care professionals continue to cycle through determined groups of susceptible ash trees throughout the city and county of Denver every two to three years with a treatment that has been proven to be 90% effective in preventing tree death. .

Original Article – 11/20/2013

Most Coloradans are familiar with the vast devastation caused by the mountain pine beetles throughout the western half of our state. Over 36 million acres of lodgepole and other type conifers have been infested or destroyed by this plague of beetles that has moved through the Rockies. Now, the Front Range is threatened by another diminutive tree-killing pest, the Emerald Ash Borer (EAB).

15% of Denver Urban Tree Population at Risk.

The emerald ash borer larvae burrow serpentine paths below the bark of the ash tree and subsequently cut off the water and nutrient flow essential for the tree’s survival. After development, the adult borer emerges in the spring and lays more eggs that again become larvae that burrow under the ash tree’s bark. The adults feed on the foliage of the tree and usually start at the top and work their way down. It may take 3 or more generations to kill an entire tree. It is estimated that one million trees, 15% of the urban tree population, is at risk in the Denver/metro area.

Boulder County Quarantined!

In September of this year an infestation of EAB’s was confirmed in a small area in central Boulder. The Colorado Department of Agriculture (CDA) has established a quarantine area that incorporates all of Boulder County and several surrounding communities including the city of Erie, plus several nearby landfills. While the emerald ash borer has no natural predators, it is not capable of flying long distances, so the quarantine and restricted movement of certain wood materials appears to be the best course of action.

Quarantine and Restricted Areas

Ash tree materials may be moved within the quarantine area, and with approved treatment and a compliance agreement from the CDA, may be taken outside the restricted areas. Besides the general public, industries most immediately affected are tree nurseries, firewood companies and cleanup and trash companies. Ash tree nursery stock cannot leave the quarantine area, all firewood classified as hardwood must be treated before it can move outside the quarantine boundaries, and waste and yard materials that include any ash or hardwood must be transported to specific landfills.

“Waste companies, particularly those in the roll-off and dumpster business, should closely inspect any load before leaving the designated area.”