Denver is facing an invasion that could change the look and feel of the city. The Emerald Ash Borer is already in Colorado, and now the city is warning it could take out swaths of the city’s ash trees.

Hundreds of thousands of trees could be gone, that’s 15 percent of the trees in the city.

The city’s Be a Smart Ash campaign is designed to convince homeowners to spend their own money to remove and replace small ash trees and treat large ones.

While tree experts have to see the actual EAB (Emerald Ash Borer) infected tree to get an estimate, several tree professionals told us for a 60 foot tree, a homeowner could pay around $1,000 to remove it from their property. The cost of removal can vary on where the tree is on your property. To treat Emerald Ash Borer infestation in a tree, it’ll cost about $12 per diameter inch. The treatment of the infestation could last a couple of years.

The city is currently spending $3 million to treat a third of the city’s ash trees. District 7 City council member, Jolon Clark says “the cost of doing nothing is astronomical. The cost of treating trees is one thing, but the cost of removal for the city, also for private residents and taking those trees out is enormous.”

A city forester says there have been discussions with the city attorney on whether they can force homeowners to treat the ash trees.