Ash borer threatens Ottawa farm's rare trees

The tree-killing emerald ash borer has been found at the edge of Ottawa's Central Experimental Farm, threatening some of its rare, valuable ashes.

"It was a bit of a shock," said David Barkley, manager of forestry services for the City of Ottawa.

The invasive beetle pest, which originates in eastern Asia, was first found at St. Laurent Boulevard and Ogilvie Road Ottawa's east end in 2008, and Barkely is surprised it managed to travel as far west as the farm in just two years.

The larvae of the beetle eat away at the flesh of the ash trees, leaving a tangle of serpentine burrows under the bark.

Central Experimental Farm, run by Agriculture and Agri-Food Canada, includes an arboretum established in 1889 to showcase exotic trees, including some that are now the largest specimens of their species in Canada. The two-kilometre street that cuts through the middle of the farm is named Ash Lane for the mature ash trees that line it and form a canopy overhead. Some are more than 80 years old.

"A number of them have come from research projects and gifts to the arboretum, to the farm," Barkley said. "[There's] a lot of history behind them and we can't lose sight of that."

Jason Pollard, a City of Ottawa forester, first noticed the threat about two weeks ago in the form of a dead tree on Prince of Wales Drive, near Baseline Road, at the southern edge of the farm. He sliced through the tree with a double-handled saw to reveal the tell-tale winding furrows underneath.

Within the farm itself, city staff expect few trees are under attack yet, Pollard said.

Farm staff will begin inoculating some of the ash trees against the pest within the next few weeks.

In addition, they have been collecting and preserving tree cuttings as scientific and historical specimens.

This week, the city is setting out 30 more traps than last year to monitor the spread of the beetles across Ottawa.