Lab Canada

Mountain pine beetle jumps tree species

Calgary, AB – The Mountain Pine Beetle is on the move not just from one tree to another, but across tree species. A group of researchers funded in part by Genome Alberta, have conclusive evidence that the Mountain Pine Beetle is now invading jack pine. The usual host for the Mountain Pine Beetle is the lodgepole pine, and now that the beetle has crossed over to another host, it is poised to move east across the boreal forest.

It has long been suspected that the beetle was invading hybrid tree species, but using newly developed DNA genotyping and location data, the University of Alberta team found that pure jack pine are now being attacked by the beetle and the blue-stain fungi the beetles injects into the tree. The discovery was largely due to the work of U of A molecular ecologist Catherine Cullingham, first author of a paper published online today in the journal ‘Molecular Ecology’.

“Tracking the pine beetle’s progression and telling jack pine from the hybrid species took a lot of work” she says. “It was tricky, but our research team used molecular markers to conclusively show that the latest pine species to be attacked are indeed jack pine.”

U of A researcher Janice Cooke points out that the “Jack pine is the dominant pine species in Canada’s boreal forest. Its range extends east from Alberta all the way to the Maritime Provinces.” 

The infected area of north-central Alberta is a gateway area into the boreal forest. The paper also suggests that apart from the new host species opening up a new range for the beetle to attack, the risk could be made worse by future climate change.

The current Mountain Pine Beetle outbreak has affected over 14 million hectares of forest land in Western Canada. It is the largest outbreak documented since record taking began 125 years ago.

The article is entitled “Mountain pine beetle host-range expansion threatens the boreal forest”.