Everything in an ecosystem is connected. A tiny sapling relies on a towering ancient tree, just like a newborn baby depends on its mother. And that forest giant needs the bugs in the dirt, the salmon carcass brought to its roots by wolves and bears and the death and decay of its peers. It thrives not in isolation, but because of dizzyingly complex connections with other trees and plants through vast but tiny fungal networks hidden below the forest floor.
It’s here, in the soil, that forest ecologist Suzanne Simard found her calling. Simard is a UBC professor and author of hundreds of peer-reviewed articles. She recently published a memoir, Finding the Mother Tree, about her journey to discover what makes the forest tick. Amy Adams and Jake Gyllenhaal bought the movie rights to the book, and Adams is set to play Simard in a feature film based on the memoir.
As a child, Simard, who lives in Nelson, spent her summers in the old-growth forests of the Monashee Mountains in southern B.C. But her connection with the forest goes back generations. Her grandfather was a horse-logger: He chose one good tree at a time, cut it down, dragged it out of the bush with horses and launched it down a steep hillside into a lake where it could be floated downriver and sold.
As those trees were taken from the forest, their selective removal let in new light that young plants greedily turned into photosynthate, sugars spurring their growth. The old trees provided shade and protection as the new trees filled in the gaps and the ecosystem continued to function as it had for thousands of years — cycles of warmth and growth, cold and decay.
When she followed in the footsteps of the loggers before her and entered the male-dominated industry in the late 1970s as a forester, Simard found herself working in a system that looked nothing like the horse-logging operations of her grandparents’ generation.
Rough roads winding along valley bottoms and switchbacking up mountainsides led to big open spaces — clearcuts — where chainsaws, feller-bunchers (heavy machinery capable of cutting down and moving smaller trees, sometimes two or three at a time) and logging trucks able to navigate those roads worked efficiently and at a breakneck pace to take as many trees as possible, feeding mills and markets, with the promise that those clearcuts would be replanted and when the trees were big enough, the process could begin all over again.
“I got my first job in the forest industry in Lillooet,” Simard says. “I loved the work because I love the bush and I love the danger of it all, the excitement of it all. But I was also conflicted because it was so different [from] what I understood, what I grew up with. It wasn’t careful — it was just exploitation.”
In those massive replanted clearcuts, Simard found a sea of dying saplings, not the promised green gold. She set out to learn why.
Finding the mother tree
The first clues the young forester found were wrapped around the roots of saplings. Healthy baby conifers uprooted from the dirt would reveal roots dangling a tangled web of fine fungal threads — mycelium — varied and brightly coloured. In contrast, the roots of sick seedlings, plucked from the hard, dry soil compacted by the machinery that had extracted the tall, old trees, were black and devoid of any mycelium.
As a young woman in an industry resistant to change, she found herself struggling to apply her observations to the work she was tasked to do: feed an industry increasingly hungry for trees while finding a way to make sure that hunger would always be satiated. Her suggestions to plant multiple species in clusters, mimicking the natural succession of healthy forests, instead of the preferred monocrop plantations of pine in neat little rows, were dismissed. While it was frustrating, she says coming face-to-face with the problems of entrenched forestry practices fuelled her curiosity.
“I think in some ways having that experience in industrial forestry and being part of the clearcutting machine myself was essential to the development of the questions I eventually asked,” she says. “I had conflicts and regrets, but it was also formative for me too.”
After working with logging companies, reluctantly flagging ancient forests for harvest, she got a job with the B.C. Forest Service and started conducting field experiments, fighting for funding and recognition of her work.
She eventually learned the mycelium were part of an extraordinary mycorrhizal network that was working with the trees to mutual benefit, carrying resources like carbon and nitrogen back and forth through the underground forest ecosystem. She popularized the term Mother Tree, explaining the ecological connections between trees is like the nurturing connection between mother and child.
She discovered that old trees feed new trees a cocktail of nutrients necessary for survival and change the ingredients of the cocktail in response to climatic conditions. She even found old trees recognize their own kin, preferentially distributing nutrients to their offspring over seedlings that took root in their shade carried there by wind or dropped by a bird or animal.
She also demonstrated the connection between different species, such as birch and fir, alder and pine, and proved through multi-year experiments that the forest-management practice of eradicating deciduous species both manually and through the use of herbicides like glyphosate was in fact detrimental to regrowth, in some cases catastrophically so.
Yet, even when she’d proved that trees share resources and communicate through the mycorrhizal network, publishing her findings in peer-reviewed journals, she found there was another network at play, a network of politicians, policy-makers and corporate interests. Her theories and discoveries were scoffed at, discredited and mostly ignored by the people who needed to listen.
“When I published my first work on connection and forests, I just got slaughtered,” she says. “Honestly, it was too much for me. I didn’t have the strength. I was raising my kids at the time. They were little tiny babies, and it was just too much.”
She persevered and shifted into academia, taking a position at the University of British Columbia, juggling her work with motherhood, grief after her brother was killed in an accident and, later, breast cancer.
“I got really depressed about climate change and then I got sick with breast cancer,” she says. “So I stopped reading about the details of climate change, because I understood it enough. And I started looking at how systems work more. I just said, ‘I’ve got to focus on these positive things.’ ”
B.C.’s forest policies still perpetuate clearcutting
Fast forward to 2015 when Simard, now well-respected and her work widely accepted and the inspiration for a character in the Pulitzer Prize-winning book The Overstory by Richard Powers, started The Mother Tree Project to continue her research on how trees communicate with each other in hopes that the discoveries can influence change, not only by increasing our understanding of forest ecology but also by presenting solutions to the problems facing B.C.’s forests as provincial policy continues to perpetuate destructive clearcutting practices.
“I’d done all this fundamental work on forests as social places, that forest trees are connected, that they share resources, they’re communicative, they’re regenerative, they’re interdependent on all these different ages of trees, between the old trees and the young trees,” she says. “And yet the work was never really applied.”
Partnering with a team of ecologists, foresters and researchers and leveraging her professorship to catalyze graduate students to tackle different aspects of the ambitious project, Simard started by establishing experimental sites in nine climatic regions across the province, sites that were chosen to better our understanding of how climate change will affect the success of forest regeneration.
“How do we protect these old trees and still be able to harvest some trees?” she asks. “And what would the patterns be as the climate is changing? As we have to migrate trees, what do they need? We’re finding out that survival of new migrants is about 30 per cent higher when they have the cover of old trees.”
It all comes back to the soil and the trade network that exists between forest organisms.
“It really is about bootstrapping up the new generations with as many fungi as it can support for a productive ecosystem,” she says. “The way to do it is to leave these old trees spread through the forest in clusters so that the old trees are protected against wind and infestations and just shock from being left alone.”
With enough old trees left behind to distribute resources where (and when) they’re most needed and shelter new growth, the next part of the process is stimulating and replicating natural systems. Encouraging native plants to remain builds the soil structure and adds diversity to the fungal species that help transfer resources from tree to tree.
Public pressure backed by solid science is recipe for change
Simard says the experiment is starting to gain traction with the likes of logging companies and B.C. Timber Sales, the government agency responsible for managing about 20 per cent of the province’s forests.
“They were reluctantly, grudgingly drawn into the project because they saw it as contributing, I think, to their social licence,” she says. “Now, those licensees are going, ‘Wow, this actually worked.’ I was just on a call with B.C. Timber Sales yesterday at this little conference and they’re saying, ‘Well, the public is pressuring us to shift to partial cutting, so we need to know about partial cutting.’ They’re talking about leaving 40 to 60 per cent of the basal area. That is a huge, huge shift.”
While partial cutting has yet to land in provincial policy, she says change, while slow, is gaining momentum through a combination of public pressure and the marriage of western and Indigenous science.
“I’ve worked in every sector — I’ve worked in industry, I’ve worked as a consultant, I’ve worked in government and academia — and I’ve pushed and pushed and pushed from inside. And the change you can make is just this tiny little incremental change, or nothing at all, or backwards. The civil disobedience [and] the protests are absolutely essential,” she says, referring to the movement to protect old-growth forests on southern Vancouver Island, where more than 200 people have been arrested, adding, “but they need the science to back it up.”
That science is what she dedicated her life to, finally coming to fruition with the Mother Tree project, but Simard warns of the urgency to protect those ecosystems for their role in fighting climate change and preserving biodiversity. Reforestation and adjusting harvest techniques is only one part of the shift needed, she says, explaining we also need to cut less and consider ecosystem values like carbon sequestration, water and biodiversity, not just the price a two-by-four will fetch on the market.
“We still need these big decision makers at the policy level, like Minister [Katrine] Conroy and the chief forester, Diane Nichols, and we need [NDP Premier] Horgan to stand behind them, to make these changes. Either we do partial cutting but we spread it over a bigger landscape or we do more concentrated clearcutting, which people don’t like and isn’t good for the forest. We need to make those two things happen at the same time: reduce the cut and save the old-growth forest and reforest what we do cut right away, but leave these old trees.”
The stakes are higher than ever, and grow exponentially as the extraction of the last of B.C.’s remaining productive old-growth continues.
“We need these old-growth forests, like at Fairy Creek, for their ability to store carbon [and] for species at risk that live there,” she says. “And these old-growth trees, we need them because the genes of those trees, the seeds, have seen many, many climates in the past. We need that legacy in order to deal with climate change in the future.”