Loading...
HomeMy WebLinkAboutEmerald Ash Borer Confirmed in Firestone - 7/30/2026Emerald Ash Borer Confirmed in Firestone Earlier this month, experts from Colorado State University Extension confirmed the presence of emerald ash borer (EAB) in Firestone. According to Firestoneʼs tree inventory, there are approximately 378 ash trees on public property, and there are significantly more ash trees on private property in Firestone. With ash trees estimated to comprise 15% or more of all urban trees in Colorado, this non- native, invasive pest poses a serious threat to urban forests. EAB attacks and kills both stressed and healthy ash trees and is so aggressive that trees typically die within two to four years after becoming infested. EAB was first confirmed in Colorado in 2013 in the City of Boulder. Since then, EAB has spread to other cities and towns in Colorado. Firestoneʼs Forester, Ryan Alolor, made the initial finding in an ash tree at Settlers Park, located in Oak Meadows Neighborhood. “Itʼs probable that the EAB has already infested other ash trees in Firestone,” Alolor said. Private trees located in the Oak Meadows and the Shores Neighborhoods are exhibiting some of the same symptoms as the trees that we found EAB in at Settlers Park. “In 2025, we treated all of our public ash trees above twelve inches in diameter and are currently in the planning phase for the remainder of our ash underneath that threshold.” EAB tips for Colorado 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 one another; and diamond-shaped bark ridges on mature trees. Find more information about ash tree identification, including a helpful app, on the CSFS website. If you have an ash tree, start planning. Decide if the overall health of the tree and the benefits it provides merit current or future treatment, or if it would be best to remove and replace it with a different species. If you are not sure, contact your local CSU Extension horticulture agent or an ISA Certified Arborist. If you do plan to treat the tree, the CSFS offers recommendations for selecting a tree care company. Plant trees. Replace ash trees in poor health with diverse species. The Colorado Department of Agriculture offers a database of registered nurseries and landscape contractors. 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. Help prevent further spread of EAB. Do not transport ash or any hardwood firewood, or any other untreated ash wood products, to other locations outside Firestone. Dispose of ash wood safely by chipping, composting, milling into lumber, or taking it to a landfill. For more information about ash tree identification, the symptoms of EAB, treatment options, and how to use ash wood, visit the CSFS website. Emerald ash borer (EAB) is a non-native, wood-boring beetle that is responsible for the death or decline of tens of millions of ash trees in the United States and Canada. This insect was first discovered in Michigan in 2002 and has since spread to at least 35 states, including Colorado. As a non-native insect, EAB lacks predators in North America to keep it in check. EAB typically only attacks ash trees in the genus Fraxinus, but has also been documented infesting white fringe tree. Mountain ash and other species are not susceptible. Share on Facebook Share on Twitter Share via Email Copyright © 2026 Town of Firestone. All Rights Reserved. 9950 Park Ave., Firestone, CO 80504 Powered by