New Brunswick

City to decide fate of ash trees in Fredericton as emerald ash borer inches closer

Fredericton city staff will spend the next few months deciding which ash trees are worth saving as the city prepares for the arrival of the emerald ash borer.

City staff will examine which trees are worth saving and put together a management plan for the fall

Mike Glynn, a forester with the City of Fredericton, says crews are trying to prevent the emerald ash borer from killing ash trees in New Brunswick's capital. (Mike Heenan/CBC)

Fredericton city staff will spend the next few months deciding which ash trees are worth saving and which will be left to die, as the city prepares for the arrival of the emerald ash borer. 

"What we need to know for the next season … is what we're going to treat, trees that we're going to remove, any potential increases to our planting program," said city forester Mike Glynn.

Glynn gave an update on the beetle at the city's development committee meeting on Thursday.

The invasive species, which destroys ash trees, has been found in Oromocto and could arrive in Fredericton any day now — if it hasn't already.

How Fredericton ash trees are being injected with pesticides to keep invasive beetle away

4 years ago
Duration 1:26
Forester Mike Glynn describes the process in which ash trees are injected with pesticides to combat an invasive beetle that has already appeared in Oromocto and Edmundston.

Glynn said the city has traps set up to detect the beetle, though staff have yet to find one of the bugs in the provincial capital. But Glynn said it's still important to plan for the ash borer's impact.

"It's a very difficult insect to detect, and although we've done a great deal in terms of detection, it can still exist and there really is no indication that it's there," said Glynn. 

Management plan

The emerald ash borer has decimated trees across Canada. (Minnesota Department of Natural Resources)

The city will look at inoculating some trees, planting new trees and removing infested ones as part of its management plan. Fredericton has about 2,300 ash trees along city streets, and thousands more in parks and other areas of the city. 

"Ultimately it comes down to the dollars and cents. If you remove many trees then you have to plant many trees and there's a cost on both sides of that," said Glynn. 

The city inoculated 21 ash trees with TreeAzin, including trees in Odell Park and Officers' Square, as part of a pilot project to determine how effective the injections are. 

The city has drilled holes in 21 ash trees so it can inject a pesticide called triazine. (Mike Heenan/CBC)

TreeAzin has been known to save trees, but only if it's injected into the tree before the emerald ash borer takes hold. 

A large ash tree can cost about $250 annually to inoculate, but removing a dead and infested tree can cost more than $1,000. 

Coun. Greg Ericson sits on the Fredericton tree commission and chairs the city's finance committee. He said that once a tree becomes infested and starts to decay it becomes a danger to the public and the city will need to take it down.

The city has 2,300 ash trees along city streets and thousands more in parks across Fredericton. (Invasive Species Centre)

"The city may not be in a position to be able to afford, from either a financial perspective or the resources required, to take down enough ash trees in a given year to keep the public safe," said Ericson.

"That's when inoculation becomes an element of long-term strategy to maintain public safety and responsible financial spending."

Ericson said the city will also look at protecting significant trees, like some in Odell Park and Officers' Square. 

Glynn said that no matter what the city decides to do, the emerald ash borer could cost it millions of dollars. 

Glynn will spend the next few months breaking down those costs and putting together a list of trees he recommends should be saved. He will present that plan to city council for approval in the fall. 


Philip Drost is a journalist with the CBC. You can reach him on Twitter @phildrost or by email at