Boulder County enlisting public in emerald ash borer battle with adopt-a-tree program

Trees in some Boulder County neighborhoods are adorned by a new hue this spring.

A series of bright orange wraps hug approximately 50 trees located in the right-of-way areas on Carter Trail in Gunbarrel as part of Boulder County's latest attempt to combat the invasive emerald ash borer.

In an effort to stop the spread of the invasive beetle, Boulder County has decided to mark all ash trees on county property as endangered and flag them for removal. However, the county is making one last attempt to save the ash trees by asking homeowners to adopt them.

It's free to adopt a county ash tree, but those who do are responsible for pesticide treatment, which is required every two years for the remainder of the tree's life and can vary in price. This has homeowners concerned about what course of action they should take.

Mike Sucato lives on Carter Trail in Gunbarrel, and, like many of his neighbors, he is concerned about the ash tree population. But he doesn't see many people adopting the trees.

"I think they change the color of the band when a tree is adopted and I haven't seen too many of those in this neighborhood," Sucato said.

Sucato believes this is due to the price and responsibility that comes with adopting an ash tree. However, the county says that this is the best way to keep the community safe and control the emerald ash borer population.

Most ash trees don't show symptoms until two to three years after infestation. If the trees are left to die after infestation, their branches and bark become brittle, making them too dangerous to remove.

The emerald ash borer is a wood-boring beetle that targets ash trees and was first identified in Boulder in 2013. It slowly kills the ash tree by living underneath its bark and slowly cutting off its nutrients, leaving the tree with a lifespan of fewer than five years.

In 2015, the county released an emerald ash borer management plan to proactively combat the beetle. The plan states, "Ash trees located within ... subdivisions within unincorporated Boulder County were typically planted by adjacent property owners or HOAs. Maintenance levels for this group of ash trees varies based on the HOA or adjacent property owner's involvement."

There are approximately 1,500 ash trees located in the public spaces of Boulder County. The fear is that a lack of ash trees would change the landscape of Boulder forever.

As part of the management plan each tree is evaluated based on its health, defects, size, location, energy factor, form, overhead utilities, proximity to the surface, irrigation and proximity to infested survey grids. If the tree is given a score of 33 or higher, then it is considered healthy until proven otherwise. The plan is estimated to be complete by 2023.

Michelle Ferguson, Boulder County's emerald ash borer coordinator, said the county is being proactive by flagging these trees for removal and encourages homeowners to adopt their own tree.

The county only allows trunk injection of pesticides, which reduces the possibility of pesticides contaminating other plants and people.

The only approved pesticides for the treatment of the emerald ash borer are emamectin benzoate and azadirachtin. The price for the treatment varies on the size of the tree and the contractor.