Emerald Ash Borer survives through -50 C temperatures

A study conducted in part by two Sault Ste. Marie scientists indicates invasive species can withstand cold weather that exceeds some of the harshest seen in Canada.

The northern Ontario scientists have discovered a new trend with an invasive beetle that will have huge implications on how risk assessment is managed going forward.

The new study indicates the Emerald Ash Borer can now withstand temperatures as cold as -50 C after traces of the beetle were discovered in Winnipeg in 2016.

"We were surprised that they were actually there because based on our research, they shouldn't have survived," said Amanda Roe, a scientist at the Great Lakes Forestry Centre.

"We've seen this adaptability in native species, but never such adaptability in an invasive species before. It's really critical because a lot of our assessment of risk to our forests is based on those limits."

The insect has already caused extensive damage in southern Ontario and places across the north, but it's rare to reach temperatures as cold as -40 C to -50 C.

That's not the same in western Canada, where the attention of researchers will now shift.

"Certainly we thought western Canada was one of those places that we thought were free from that risk," said Chris MacQuarrie, a scientist also at the Great Lakes Forestry Centre.

"There's more work for us to do to try and understand and do something about those risks to try and save those trees."

Places like Winnipeg, Edmonton and Calgary have an abundance of ash trees that could be impacted by the existence of the Emerald Ash Borer.

Roe said the next step will be to develop an approach that recognizes how the beetles prepare for the cold weather and what triggers those changes.