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Don’t judge a tree by its cover: Winter tree & EAB treatment guide

DENVER — Although winter is the time when trees go dormant, it is a good time to start planning for tree care. It might be hard to tell in the winter, but not all ash trees are healthy and thriving. They may look okay on the outside, but the inside might be another story, and no matter the time of year a tree professional can help assess your tree.

For example, a large ash tree in Louisville was recently removed causing a bit of stir in the neighborhood. The tree provided valuable shade to neighboring houses close to the downtown area. But, despite the healthy exterior, what couldn’t be seen on the outside was that the center of the tree was hollow. A hollow tree can be a major safety issue.

“A cavity in a living tree can contribute to a tree being unsafe,” said Sara Davis, Urban Forestry Manager, Office of the City Forester, City and County of Denver. “When a tree develops problems, it is frequently difficult to decide when to replace or remove it. The one option you shouldn’t consider, however, is treating or replacing your ash tree yourself if you’re not a licensed tree professional.”

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1st Grade Ashvocates Help Spread EAB Awareness in Denver

DENVER — Ashvocates at Denver Public Schools’ Downtown Denver Expeditionary School (DDES) hit the city streets to learn more about ash trees, Emerald Ash Borer  (EAB) and ways to combat the borer. These students know that the impending arrival of the EAB is nothing to kid about.

“We should protect ash trees,” a DDES first grader said. “Ash trees make oxygen and shade. And without ash trees, we’d be so hot! Please help save the ash trees!”

The Expeditionary Learning approach to teaching and learning makes subjects come alive for students by connecting learning to real-world issues and needs. By utilizing Downtown Denver as a campus, DDES students were able to identify, touch and feel many of the ash trees lining the public streets. When asked how to treat trees for EAB, one student said, “You can put special medicine in the trees.”

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Emerald ash borer drone research ongoing in Colorado

BOULDER, Colo. — An aerial assault has been launched on emerald ash borer (EAB), beginning where the invasive pest was first found in Colorado.

Arbor Drone, Spectrabotics, and researchers from Colorado College began collecting data this summer using drone flights over southwest Boulder to study trees affected by EAB. Arbor Drone’s Dan Staley told The Denver Channel that the main purpose of the Boulder drone flights was to use a multispectral sensor to study the light reflectance of ash trees attacked by EAB.

The City and County of Denver funded this early drone study to better manage EAB when it arrives in the Mile High City, as part of its Be A Smart Ash campaign.

Emerald Ash Borer to offer scares at Denver Halloween Parade

DENVER — The emerald ash borer will be on hand in all its horror at the inaugural Broadway Halloween Parade on Oct. 21, offering a taste of the scary reality the invasive forest pest presents Denver’s ash tree population.

Hosted by the Broadway Merchants Association and City Council Lucky District 7, the community-friendly Broadway Halloween Parade will begin at 6 p.m. in the eclectic and funky Heart of Broadway. Specifically, the parade route will stretch from West 3rd Ave. to West Alameda Ave. along South Broadway.

The parade is set to feature various spooky floats, bands and marchers, and all attendees are encouraged to join in the fun by wearing a Halloween costume. And yes, not only will there be an emerald ash borer (EAB) in attendance, the Be A Smart Ash campaign will be passing out a pair of fun trick-or-treat bags for all kids — and maybe even a few adults — in attendance.

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While enjoying Denver’s fall color, take time to appreciate our ashes

DENVER — As a natural prairie, Denver wasn’t blessed with a host of native trees. That, in the humble estimation of Denver City Forester Rob Davis, is what makes ash trees worth savoring every fall.

“Colorado in general doesn’t have a lot of big shade trees that end up with a nice red or purple fall color,” Davis said. “So for me, fall is the time that I realize just how many ash trees we have in Denver.”

And that’s important for Davis, because he knows what’s coming: the emerald ash borer (EAB). The tiny green invader feasts on ash trees, and it’s now the most destructive forest pest in U.S. history, having caused billions of dollars in damage to ash tree populations in more than 25 states.

EAB was discovered in Boulder in 2013 and in Lafayette earlier this year, meaning it’s just a matter of time before it arrives in Denver and poses an immediate threat to the 1.45 million ash trees in Denver. That’s right, folks: 1 in 6 Denver trees is an ash. And the first step when it comes developing our EAB defense plan as a city is learning how to identify ash trees.

As far as fall color goes, green ashes turn a vibrant yellow. That’s great and all, however it somewhat pales in comparison to the white ash, which can change a whole host of colors from deep purple to a lighter red.

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Colorado tree climbing company raises EAB awareness

DENVER — Enjoying trees from the ground is great in its own right. But for Harv Teitelbaum, he gains a whole new appreciation for trees once he’s up in the midst of one.

That’s why Teitelbaum started Tree Climbing Colorado alongside his partner Griëtte van der Heide 15 years ago: to help people — especially kids — begin to see and appreciate trees in a whole new light. The two spoke with the Columbine Courier about their efforts to raise a greater level of appreciation for trees, including their recent endeavor to help the City of Denver raise emerald ash borer awareness at the International Society of Arboriculture’s annual tree climbing competition in Washington Park this summer.

“You can’t believe how a tree looks different from up there,” van der Heide told the Courier. “It changes everything.”

(Photo Credit: Chancey Bush, Evergreen Newspapers)

A man jogs among ash trees in Denver's City Park, all of which are vulnerable to emerald ash borer (EAB).

Help Denver fight EAB by mapping your favorite trees with Curio

DENVER — Your friendly City Forester has mapped each and every one of the public ash trees in Denver as part of its effort to prepare for the inevitable arrival of emerald ash borer (EAB). As the most destructive forest pest in U.S. history, EAB has decimated ash tree populations and caused billions of dollars in damage in more than 25 states and parts of Canada.

But it’s not just ash trees. The city has actually mapped all of Denver’s public trees, giving you the chance to learn more about the trees around you and the benefits they provide. You can give them all a look using the interactive map on this very website.

But that may leave you with intense FOMOOMT — Fear Of Missing Out On Mapping Trees. Not to worry. You can now join the tree mapping party in Denver thanks to an app called Curio.

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Video: Planting unique trees may protect Denver from EAB

DENVER — Getting the word out about the emerald ash borer (EAB) and its potential impact on Denver’s 330,000 ash trees is a full-time job, and our friends at 9NEWS — more specifically, the producers of the show “Colorado & Company” — have been a big help.

Our very own friendly Denver City Forester Rob Davis appeared on the show recently, explaining whether EAB has been found in Denver, how many vulnerable ash trees we have in Denver and why they’re valuable, how you can identify an ash tree, the tell-tale signs of EAB, whether it makes sense to keep or replace your ash, your EAB treatment options, the city’s plan to treat Denver’s public ash trees and potential trees you can plant besides ash to help diversify and protect our urban tree canopy.

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Denver City Forester Rob Davis poses among the ash trees he wants to save from emerald ash borer in City Park.

CPR: Denver proactive in battling emerald ash borer

DENVER — If Denver City Forester Rob Davis is looking to get under his family’s collective skin, all he has to do is start climbing an ash tree looking under the bark for signs of emerald ash borer (EAB).

“I drive them crazy, because I do it all the time,” Davis told Colorado Public Radio. “I’m always looking for (EAB). I’ve even climbed trees at a middle school, just thinking I’m going to find it. So sure.”

EAB is yet to be discovered in Denver, but consider its discovery in Boulder in 2013 and in Lafayette earlier this year, the Mile High City desperately wants to be prepared for what Davis called “single most destructive urban pest that Denver will ever have in its urban forest.”

From Denver’s interactive ash tree map to its efforts to guide residents about their treatment options to this very website and campaign, BeASmartAsh.org, Davis went on to explain to CPR in detail the $2.97 million, 10-year plan the city has implemented to try to cement Denver’s legacy as one of preparedness when it comes to EAB.

(Photo Credit: Colorado Public Radio)

Emerald ash borer discovered in Lafayette, Colorado

LAFAYETTE, Colo. — Emerald ash borer (EAB) has been discovered in Lafayette, the Colorado State Forest Service (CSFS) confirmed on Wednesday. Lafayette is now the third city in Colorado facing an EAB infestation.

Not entirely unlike the mountain pine beetle, which decimated pine trees across hundreds of thousands of acres in Colorado’s high country beginning in 2008, EAB has decimated ash tree populations in more than 25 states and parts of Canada, causing billions of dollars in damage over the last 15 years.

CSFS community forestry program manager Keith Wood also confirmed Wednesday the newly found infestation in Lafayette remains within Colorado’s EAB quarantine zone. That zone includes Boulder, where EAB was discovered in 2013, and Longmont, where EAB was discovered in 2016. Lafayette is less than 13 miles from each city.

“Having a new detection in this area was not unexpected,” Wood said. “But it certainly highlights the need for Front Range communities to be planning now, before EAB arrives.”

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