North

Glimpsing the future: Researchers predict how fires will change N.W.T. forests

Researchers are studying how more frequent and intense forest fires will change what grows in N.W.T. forests.

'It's not like the whole forest is doomed by any stretch, but there will be some changes'

Daniel Thompson holds a fire scarred tree. Fire scars form when fire kills a portion of the tree, but the live portion continues to grow around it. Researchers are studying how more frequent and intense forest fires will change what grows in N.W.T. forests. (Rachel Zelniker/CBC)

A group of forest fire scientists are studying areas of forest in the Northwest Territories that have re-burned in the past 15 years to try and understand what the future boreal forest might look like.

"We're seeing more and more big fire years in the past decade or so," said Daniel Thompson, a forest fire scientist with the federal government.

"That means we're expecting to have more fires in younger forest stands," he said, which could result in a very different kind of forest in the N.W.T.

"Trees have evolved to be burning every 70 to 120 years," explained Thompson.

"But if they're now burning at 16 to 18 years, we're wondering whether the seeds are going to propagate in the same way, are the plant communities going to react in the same way?"

Thompson and his team spend hours hiking through charred forest trying to answer those types of questions — and they've learned a few things so far.

"It's not like the whole forest is doomed by any stretch, but there will be some changes." 

Fire scientist Marc Parisian surveys the landscape just outside Reid Lake Territorial Campground. The group hikes for hours looking for the right area to study. 'We need a uniform patch that hasn't been bulldozed or interfered with by humans,' he says. (Rachel Zelniker/CBC)

'A birchier forest'

According to Thompson, pine forests often survive low-intensity surface fires, which primarily burn leaves, pine needles and fallen branches located at ground level — "like the big fires north of Fort Providence in 2014."

However, in areas where severe crown fires — which burn through the top layer of foliage on a tree — have destroyed pine and spruce "we could see a birchier forest because birch seems to be able to come in really quickly."

Thompson said that could mean a change in the way fires burn in the territory as well.

"Birch is that sort of a broad, wet leaf, so in the summer once it's leafed out, it doesn't burn as vigorously as say a spruce fire."

Right now, the majority of fires in the N.W.T. are caused by lightning during the summer months — and birch is "really good at slowing some of those down."

But it's hard to say whether that will be the case 50 years from now.

There could be more fires in the spring, Thompson hypothesized, especially if there are more people living in the North and therefore more human-caused fires.

"Birch doesn't do much for you at that time, so there are a lot of unknowns."

Thompson removes a section of the scarred area of the tree and counts the rings to determine when fire scarred the tree and how many years it was between fires.

Future forest management

Thompson and his team hope their research will help future forest management in the Northwest Territories.

"Helping forecast what the forest is going to look like... that is something a community fire smart plan might use," he said.

"There's also a pellet mill going in in Enterprise, so this sort of information helps them forecast the future wood supply."

But when it comes to trekking through burned forest day after day, Thompson said the motivation is personal.

"Clearly we have a wildfire problem in Canada, and there are real challenges of how to properly live and deal with [it], and so anything the group of us can do to live with fire better is a great feeling."