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Arborists: The Unsung Tree-Care Pros Who Keep Our Trees Growing Strong and Living Long

The weather is slowly warming up, birds are more frequently chirping and the sun’s setting later—which means spring must be approaching in the coming months. This also means it’s time to start preparing for your spring gardening and tree care needs. And no one is better equipped to help get your trees ready for spring than a tree care professional, also known as an arborist.

What is an arborist?

An arborist is a specially trained tree care professional who has expertise on how to plant, care for and maintain trees. In order to perform tree work in Denver, all contractors must be licensed and insured by the city. Licensed arborists help the City of Denver and property owners maintain private and public trees through tree removal, pruning of dead, diseased or damaged branches, and treatment of insects and diseases. This maintenance helps ensure our urban forest remains heathy and resilient and prevents potential damage to our properties, city rights-of-way and utilities.

What does an arborist do?

Think of arborists like a primary care provider for your trees. They can help assess a tree’s condition, provide recommendations based upon the needs of the species and complete the necessary work, ensuring the health of the tree. Services arborists can provide include:

  • Pruning: Arborists can help you determine what kind of pruning your tree needs, including improvement of health, appearance and safety of the tree. This may include removing limbs that interfere with utilities or structures or obstruct streets or sidewalks. While some pruning can be done on your own, if you’re pruning a large branch or anything from your tree that can’t be reached from the ground, be sure to hire a tree care professional.
  • Tree removal: Some trees, like ash trees, are susceptible to an invasive insect called Emerald Ash Borer (EAB) which impacts all ash species and quickly kills untreated trees.  If you need assistance removing a right-of-way ash tree, Denver’s Office of the City Forester can potentially help through the Ash Tree GAP removal and replacement program. Thyronectria Canker is increasingly common on honeylocusts and is easily spread between trees if pruning equipment isn’t properly disinfected between cuts.
  • Emergency tree care: Removing or pruning storm-damaged trees may be necessary after severe weather events to keep trees healthy and to ensure broken or damaged limbs don’t pose a risk to you or the public’s safety.
  • Planting: Arborists can also help with getting a new tree off to a healthy start by assisting with planting and creating a care plan that you can implement with ease. If you’re interested in planting a tree in the public right-of-way adjacent to your Denver property, you can apply for a free tree.

Why should I hire an arborist?

Trees are assets on our properties. They provide natural beauty year-round, summertime shade and a place for our flying friends to rest their wings. They increase the value of our homes, provide numerous environmental benefits and improve our quality of life and mental health. They’re also an investment—meaning they require proper and regular care. When it comes to caring for your tree, arborists are specially trained and equipped to perform the necessary work.

Depending on what’s required, tree work may be dangerous for homeowners to perform themselves. Licensed arborists are insured and specially trained in safety precautions while treating trees and will come to your property prepared with the appropriate equipment and training to keep themselves, the public and your property safe while caring for your trees. Every tree is unique, and each requires a different plan of care.

What should I look for when hiring an arborist?

When looking to hire tree care professionals, you may want to make sure the company has an International Society of Arboriculture (ISA) Certified Arborist on staff. This certification ensures an individual is proficient in the competencies needed for proper tree care. ISA Certified Arborists have knowledge in areas like tree biology, diagnosis, maintenance practices, proper safety procedures and other subject and practical areas within the tree care industry.

Where can I find an arborist in Denver?

Denver’s Office of the City Forester provides a helpful list of tree care professionals in Denver.

Professional, trained arborists know how to properly maintain trees for the safety of the public and the health of the tree. The best way to ensure your tree stays healthy is to hire a professional arborist. Watch this video to learn more about arborists.

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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A pair of certified arborists tend to an ash tree in Denver's City Park | Be A Smart Ash Denver

Emerald ash borer treatment options for your Denver ash tree

DENVER — The emerald ash borer (EAB), which feeds on ash trees and is now the most destructive forest pest in U.S. history, has arrived in Colorado, and it’s knocking on Denver’s door. That fact is overwhelming in its own right.

But you might find yourself even more overwhelmed by all the treatments options available to protect your ash tree from EAB. That’s where we come in!

For starters, there are four treatment options that have been examined at length as part of a multi-state insecticide study from Colorado State, Ohio State, Michigan State and Purdue universities. Below is a breakdown of each option.

You might also be happy to know that your Friendly Denver City Forester has put together a list of Certified Smart Ash tree professionals, all of whom have the right mix of know-how and tools to safely and effectively protect your tree from EAB.

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