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In the forest, a B.C. scientist discovers trees take care of their own

UBC professor Dr. Suzanne Simard’s book describes research into fungal networks’ role in forest health
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Dr. Suzanne Simard of Nelson, a professor of forest ecology at UBC, is the author of Finding the Mother Tree. Photo: Brendan Ko

In the 1990s when Nelson’s Suzanne Simard was a researcher for the B.C. forest ministry, her ideas were considered to be on the fringe.

Governments and the forest industry ignored her when she presented research showing that trees communicate with each other through a complex underground network of mycorrhizal fungi.

She conducted experiments while earning her PhD that showed that there can be hundreds of kilometres of mycelium networks under a single footstep, connecting individual plants of the same species but also different species, with nodes and links, somewhat like the internet.

Since then Simard has become a professor in forestry at UBC, and has continued to do groundbreaking scientific research into mycorrhizal fungi and networks, finding that trees have complex ways of distributing nutrients and supporting each other, and that forests behave as a single organism.

Her research has been replicated elsewhere and her ideas have become mainstream.

But not in B.C.’s government or forest industry, where the implications of her work would upend the way trees are grown and harvested here.

“The industry really shouldn’t be clearcutting if we’re trying to save carbon and save biodiversity and foster regeneration,” she told the Nelson Star, “We should be doing partial cutting.”

Simard describes the biology and the politics of her work, as well as her personal journey as a researcher, in Finding the Mother Tree: Discovering the Wisdom of the Forest. The book was an immediate hit when it was released May 4, and currently resides at No. 5 on the New York Times bestseller list.

Mother trees are the biggest, oldest trees in the forest.

She originally called them hub trees but switched to mother trees because “these trees nurture their young. A mother tree can be connected to hundreds of other trees. We have found mother trees will send excess carbon through the network to seedlings and this increases seedling survival by four times.”

Mother trees recognize and prioritize their own seedlings, she says, giving more nutrients to them than to others.

In a series of experiments, Simard discovered that trees transmit warnings to their neighbours about dangers such as spruce budworm.

“We were infecting these Douglas fir trees and we found that these trees, when they were stressed out, sent defence signals through the mycorrhizal network to the ponderosa pines, (which then) amped up their DNA production to create more defence enzymes, and that protected them against the spruce budworm as well.”

Simard has lived in Nelson since 2006. Her mother was born in Rossland and her grandparents lived in Nakusp, Edgewood and Mabel Lake. Her paternal grandfather was a horse logger.

“I got to know forestry from that perspective,” she says. “I grew up in the woods, so I knew the forest is this regenerative place where from selective logging the forest just rebounded immediately. You couldn’t even tell that he’d done it.”

Simard lives full time in Nelson during the pandemic, but otherwise divides her time between here and UBC.

In her 2016 TED Talk, Simard states that “forests are not just trees, they are complex systems of hubs and networks that overlap. They are vulnerable, not only to natural disturbance but to high-grade and clearcut logging. You can take out one or two hub trees but there comes a tipping point.”

She says arrival at that tipping point is being hastened by climate change, and that Canadian forests are now net emitters of carbon, where they used to be a carbon sink. In other words they are losing more carbon than they are gaining.

“And that’s huge on the world stage,” Simard says. “You can actually mitigate the loss of carbon from these sites by partial cutting, because you don’t lose nearly as much and you can actually keep it in the ground and keep it in the trees.”

She said this is common knowledge among experts but it has not been taken up by governments or industry.

“There’s more and more research that’s been done that shows biodiversity is correlated with productivity and health of ecosystems across the board.”

Simard says partial cutting should be done in second growth forests, because they have already lost a lot of their carbon, and old growth should be left alone.

“Old growth forests (like the local ones in) Incomappleux and Lardeau, those forests are full of carbon, that’s what we’ve measured. They’re just rich, rich, rich, in carbon. So are all the coastal forests, they’re unique in the world, they’re hotspots and there is lots of data to show this, and we should not be going in and cutting those forests.”

Simard says forests need all their natural inhabitants, plant and animal. The tendency of foresters to use herbicides to eliminate deciduous trees in favour of more commercially valuable conifers is a direct threat to healthy forest biodiversity, and is an example of how far behind the times forest policy is.

“The plan is to take every last stick from the working forest, basically. The government needs to shape up. And the problem that they have is that they’ve sold us out. The big corporate industry giants have consolidated, they’ve got their hands on most of the tenure, we’ve made commitments to them for volume harvested, and the government doesn’t want to reduce the timber volume that is cut annually.”

The greater the biodiversity, she says, the better we are prepared for extreme events like insect outbreaks or forest fires. Having lots of big trees in a forest reduces the risk of wildfire.

“Because they have thick bark. They’re deep rooted, they bring water up from down deep through a process called hydraulic lift, and they redistribute that humidity, keeping the forests moist.”

But when we replace them with plantations of conifers like pine and fir, and then weed out the deciduous trees and shrubs, she says, forests become more flammable.

At UBC, Simard teaches a variety of courses in forest ecology. She says her students are very receptive to the research outlined in her book.

“And it’s not just my students. The most common response I get on email, which I get lots and lots of, is ‘I always knew this in my heart.’ That’s the most common response, whether it’s from a little kid to a grandmother to a CEO of some big international corporation, they all basically say the same thing: ‘I always knew this in my heart.’”

Related:

Province’s response to old growth forest report falls short, says Nelson scientist

B.C. urged to protect at-risk old growth while it works to transform forestry policy

Breastless Friends Forever: How breast cancer brought four women together



bill.metcalfe@nelsonstar.com

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Bill Metcalfe

About the Author: Bill Metcalfe

I have lived in Nelson since 1994 and worked as a reporter at the Nelson Star since 2015.
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