Ash borer infestation forces city to cut trees

City crews were out cutting down ash trees Thursday in an effort to remove trees that have been infected by the emerald ash borer.

The emerald ash borer, which is native to eastern Asia, arrived in the Ottawa area in 2008. The insects have been slowly munching through the city’s 75,000 ash trees ever since, city forestry officials said.

Michel Bellemare, the city councillor for the Beacon Hill neighbourhood, stood by Thursday as crews cut down infected trees.

 "This is just the beginning of what we’re going to see throughout our neighbourhoods across Ottawa over the coming decade," Bellemare said.

Forestry crews planned on removing 37 mature ash trees from properties along Rainbow Crescent Thursday, and said they expect that more than 100 ash trees will be cut down across the city this winter.

Jason Pollard, who works for the city’s forestry department, said cutting down they trees won’t slow the spread of the ash borer, which is expected to keep moving through city’s ash trees.

"We're not cutting these trees to manage the population of emerald ash borer," Pollard said. "We can look at our examples from other parts of southern Ontario where they did attempt that back in 2002 and 2003 and it wasn’t successful."

Larvae of the beetle feed under the tree’s bark, leaving a trail of tunnels filled with sawdust. The beetles make holes in the bark when they emerge from the tree as an adult. The damage eventually kills the tree.

Pollard said the city is cutting infected trees down because of safety and liability issues. He said forestry officials think some of the ash trees will survive the infestation, adding that the city won’t be cutting down healthy trees. 

The city has planted 1,000 trees across the city in an attempt to replace infected trees and preserve Ottawa's canopy. It has also launched a program that allows residents to request a free replacement tree — of a different species — from the city.