PORTLAND, Maine — Thousands of Portland’s trees are on borrowed time.
The emerald ash borer is gaining more of a foothold in the state's largest city. After being spotted in far Aroostook and southern York counties in 2018, Portland foresters put out traps and collected the non-native, invasive insects in Payson Park in 2019.
According to the U.S. Department of Agriculture, the borer hails from eastern Asia and was first detected near the U.S. in Canada in 2002. The bugs feast on and kill ash trees and, as Portland City Arborist Jeff Tarling explained, unlike in their native territories, they face no known predators yet in America.
"In places in Asia where this insect was found, there’s natural control," Tarling said. "And here in the United States, there isn’t."
Tarling and other tree experts have been encouraging landowners to have licensed professionals inspect their trees. There is no way to stop an infestation from killing an ash tree, but there is a preventative injection that can provide two years of protection.
Davey Tree Experts District Manager Chris Plante put the borer spread bluntly.
"It’s gonna decimate the ash population," Plante said.
Going to decimate, not might decimate. That’s a bleak outlook, but one he still wants homeowners to face head-on; saving trees and saving them money, because while he said removing a healthy ash can typically be straightforward, Plante’s crews won’t climb an ash with borers inside.
"If it has ash borer in it, the price is going to be astronomical, because you’re talking cranes," Plante said.
Since the Payson Park detection, borers have infested trees on the opposite side of town on District Road near the Westbrook city line. Tarling was forced to cut them down, with more likely coming down in the future.
But Tarling didn't expect to find the latest victims: all seven ashes that shade the asphalt parking lot of Lincoln Middle School. The trees are rare streaks of green in a neighborhood tightly packed with single-family homes with small yards. Whatever ash borers ate into those trees, they worked hard to find them.
They, too, are scheduled to meet a chainsaw come spring. But, if there is a silver lining in the infestations, it's found at Lincoln Middle School—where students will help remove the trees, plant new ones, and learn biology in the process.
"Instead of just cutting the trees down and sanitizing it, working with the students and letting them learn about it, they’ll bring that information home to their parents and others in the community," Tarling smiled.
He hopes word of mouth moves faster than an ash borer.