Invasive beetle coming

Photo: The Canadian Press

An invasive beetle that has already ravaged millions of trees in Central Canada and the U.S. has made its first appearance in the West.

The emerald ash borer, a highly efficient killer of ash trees, has been confirmed in a tree in a Winnipeg neighbourhood.

"At this point, we have to assume it's as bad as it sounds," said Krista Ryall of the Canadian Forest Service.

Ash borers, originally from China, are already so prevalent in Ontario, Quebec and the eastern U.S. that scientists fear some species of ash may be wiped out. The International Union for Conservation of Nature has said the toll may eventually reach eight billion trees.

"All of our North American ash species are vulnerable," Ryall said.

Winnipeg has 350,000 ash trees shading its boulevards and neighbourhoods. Now, their future is shaded.

Studies suggest the bugs are perfectly capable of surviving a Winnipeg winter and they have few natural predators in Canada. Ash borers can infest a tree for a couple seasons before the impact is noticeable, giving it time to multiply and making it hard to spot.

"There's nothing you can see. The tree looks perfectly healthy, then end of season or next year, it looks suddenly dead," said Ryall. "And it's been infested for several years."

Federal officials will conduct a visual survey for more infected trees in the neighbourhood. A closer survey that involves pruning branches and looking under the bark will follow.