Longmont Could Lose Its Ash Trees in Eight Years to Emerald Ash Borer

Forget Zika. There's a new reason to worry this summer.

The first confirmed case of an emerald ash borer infestation in Colorado outside Boulder was detected this week in Longmont. An arborist found and reported what he thought was the tree-killing pest in an ash on private land near Ninth Avenue and Hover Street.

The half-inch-long dark-green beetle is active from late May through July, when it feeds and lays its eggs. Because it can kill a tree within two years of contact, finding an emerald ash borer in one little ash tree puts the rest of Longmont's 43,000 at risk.

“I've heard our forester say it's possible that within eight years, we could lose all of our ash trees,” says Rigo Leal, spokesman for the city. “It's very concerning, because there's no easy solution. Many of the proposed solutions are expensive, so that's money we have to try and budget for and find through the budget process. Boulder has been dealing with this issue for three years now, and they don't have a great handle on it.”

After the pest was first found in Boulder in 2013, home to some 98,000 ash trees, the state Department of Agriculture created a “quarantine zone” around the county to protect the rest of Colorado's ash trees, which make up about 15 percent of all trees in the state. Manufacturing and crafting with ash is prohibited within the quarantine area, as is transporting ash nursery stock outside the area. Longmont city officials aren't sure if the emerald ash borer made its way outside Boulder via natural spread or by accidental human transport.

When the bug first arrived in Colorado, many cities, including Longmont, adopted ash borer management plans to prevent a wider infestation. In 2017, Longmont planned to begin a "protective chemical treatment regiment" for about a third, or 900, of Longmont's public ash trees, according to a city statement. “Due to the confirmation of EAB in Longmont," the statement continues, "the City is suspending its removal and replacement efforts, and all identified resources will now be put toward protective treatment. Application on the first 300 trees will take place this summer.”

The change in plans has put the city's forester in an awkward position, Leal says.

“It's his job to preserve trees, so he feels like he's in a tough position where he's going to have to determine what trees need to be removed versus preserved. It goes against his natural job description.”

The city will start to plant a wide variety of trees to lessen its susceptibility to the emerald ash borer. Residents are being asked to inspect their trees and contact an arborist if they find anything suspicious.

Find out how to identify an ash tree here