Suzanne Simard speaks at the 2023 Cortes Community Forest AGM

The Mother Tree Project began in one Lower Mainland and nine Interior forests. They recently expanded their research on the coast, where Dr Suzanne Simard says the forests are richest in terms of biodiversity. A team came to Cortes Island at the invitation of the Cortes Community Forest Cooperative, and students from the Cortes Island Academy will be taking part in a research propject later this year. Dr Simard described the Mother Tree Project’s work on Cortes, and responded to questions, at the Community Forest’s 2023 AGM.

This is an abridged transcript taken from the ZOOM audio. 

Looking from the sparsely covered vegetation beneath a heavily treed forest canopy to the more abundant vegetation in a cleared area – Photo by Roy L Hales

Suzanne Simard: “I just wanted to thank you for having me and the Mother Tree Network, and I’m joined here by Dr Robin June Hood and Jean Roach.” 

“We came to Cortes last summer, on invitation by the Cortes Community Forest, to help inform possible future scenarios for forest management, and we are really delighted to join you in doing that. You live on a very special island with a lot of diversity and a beautiful community of people, who are very active, informed and want good things for their island.” 

“We wanted to start from a place of being informed about the ecology of the island.  Three of the students from the Mother Tree Network, including Alyssa Robinson, Liam Jones, and Joey Timmermans, spent about a week or two in the fall looking at the forest and then previous harvesting practices and their impacts on regeneration, biodiversity and carbon pools (or carbon stocks) in the above ground plant community, the trees mostly.”

“The idea was to look at these things to inform possible future forest management scenarios.  We were also testing a little bit of Bruce Ellingsen’s hypothesis that a continuous canopy cover forestry would be good for the ecosystems.” 

“We just looked at basically five sites, and we looked at the harvesting practices at those five sites, which were:

  • A clear cut at (Von Donnop?), 
  • Seed tree – leaving 25 stems per hectare at Squirrel Cove, 
  • Seed tree -100 stems per hectare at Larson’s Meadow,
  • What Mark Lombard called a ‘string of pearls’ at Green Mountain, which are small gap openings, 
  • 60% retention at Carrington.”  

“We went into each of these openings and compared three things: carbon pools, regeneration and biodiversity between those treated areas and control forests that were nearby.”

“We have our methods, which kind of follows the standard National Forest Inventory methodology. It’s a truncated version of that.” 

“I just wanted to give you some of the brief overview of the results, and then you can ask me some questions.” 

“What we’re looking at is a gradient of openings and a gradient of retention of trees from no retention, which is the clear cut, all the way up to 100% or natural retention.” 

“Generally, what we found is that the higher the tree retention, the higher the carbon pools that are left behind. So obviously control forests, where you’ve done nothing, have got the highest carbon pools.”

“Just to give you an idea of the numbers: 

  • in the control forest they were at a high of 350 tons per hectare in the above ground forest, the above ground pools, that’s not including the soil which will have about equal amount below ground. 
  • The clear cut had 32 tons per hectare, so more than 10 times less.
  • 100 stems per hectare had about 120 tons per hectare, so about a third of the control forest.  
  • The 25 stems per hectare had 66 tons per hectare, which is about a sixth of the control forest.” 

“In other words, you lose about 10 times more from the carbon pool when you clear cut, or you get 10 times less than a control forest.

“The more trees you retain, the bigger the carbon pools. It’s almost like addition, right? It’s mathematically additive.”

“In these control forests, we also have the highest cover of moss species.  Mosses are really important in these ecosystems because they provide habitat for all kinds of creatures, like slugs and snails,  the soil, food web, and so on.”

“Whereas in the clear cuts, there is basically no moss cover left. It’s  obliterated and  this reflects what we see in other clear cuts around the province. Of course it will slowly recover over time, to a certain degree, but the moss species richness will remain a lot lower than in the control forest.”

“That was just the mosses, the plant diversity and abundance and richness is basically the highest in the clear cuts. That’s because you’re opening the forest up. A lot of light comes in, especially into the disturbed mineral soil area and so richness of those plants goes up. Generally salal also increases in abundance, especially over time, and you have greater  biodiversity. That’s also what we see in clearcuts around the province.” 

“That’s not really new, the important thing here is that richness, biodiversity goes up, but the plant community changes over alot, and that is where you’re looking at whether the functionality of the ecosystem is actually a good function or not.” 

“What you’re basically doing is shifting over to communities that are dominated by bracken fern and salal, away from a moss/sword fern kind of community.”

“As far as regeneration goes, we found there was very little regeneration in the clearcut. They’d been planted, but as for the natural regeneration – there was hardly any. The clearcut was only a of couple years old, so there will be some (regeneration) that comes in over time.”  

“In the higher retention forest, anything that was over 40% cover of the overstory- so that includes  the  understory areas in the high retention as well as the control forest- there was also no natural regeneration.” 

“There is a sweet spot here of natural regeneration that occurs between about 10% overstory cover and 40% overstory cover.  We found that there was a shift towards Cedar at the lower range. So at 10% and below we have the best Cedar regeneration and then Douglas Fir and Hemlock was best closer to 40% overstory retention.”

“What this tells us is there are a lot of trade-offs.”  

“If we’re looking to manage these forests for carbon pools, which of course has got value for many reasons: carbon pools are correlated with biodiversity. We know that you’ll have more bird species diversity, we think more mammal diversity. You’ve got more moss cover, which is better for the microclimate of the forest. Carbon pools are all higher in the control forest or where you have done nothing.” 

“At the other end, if you clear cut, you  get more early plant biodiversity, more early successional plant communities.”

“But that doesn’t come along with natural regeneration necessarily, you’re going to have to plant those areas in order to reforest  them. So clear cutting doesn’t look that great either.” 

“In between, there is a retention level between 10% and 40% where natural regeneration is really good. The higher retention that you have where you’re retaining trees, the more Douglas Fir you have, the more Hemlock you have and you can retain carbon pools at the same time. So I think on balance, if you’re trying to balance all of these things, that 40% cover is probably ideal, but of course you don’t necessarily want to do the same thing everywhere and always have the same objective everywhere.”

“That basically sums it up. Please ask any questions.” 

Question Period

Anonymous: “My question was about the carbon pool aspect of your study, and I was wondering if you found it was a linear relationship as it went from clear cut through to the control, if it was linear across the board, or if there was a different relationship, as you saw through these different stages?”

Suzanne Simard: “I would call it additive rather than linear. The more trees you leave behind, the more carbon you have. Each tree is contributing a certain amount of carbon to that big pool, that above ground pool. So the  more trees you leave behind, the bigger the carbon pool.” 

“However I’ll put a caveat on that, in that the larger trees, when you leave larger trees behind, they hold a lot more carbon than smaller trees. And that’s not linear,  it’s the volume of the tree that is so important. Some trees, the mother trees if you will, or the old veteran trees or the wolf trees – however you want to call them – those ones can have a disproportionate amount of carbon in them relative to the rest of the forest. So leaving the biggest trees behind is the most protective of those carbon pools. 

Bruce Ellingsen: “The reason you’re looking for the carbon pool in the research you’re doing – is that because carbon is such a basic element or atom in the  molecules that go up making nutrients in the forest?” 

Suzanne Simard: “Thanks Bruce, that’s a great question. So why is carbon so interesting?  One thing is we’re made of carbon for the most part. Photosynthesis is the conversion of light energy into energy that is taking CO2 and water and turning it into sugars. Everything else in the  food chain down the line depends on that autotrophic photosynthesis. All living creatures are made of carbon and so it is a really a representation of life itself.” 

“The danger of just fixating on carbon is that you can forget that  there’s patterns in carbon and those patterns are important to the functioning of ecosystems. So we have to think about not just the amounts, but how it’s distributed.” 

“It is a really good proxy for life and it’s a good proxy for productivity and integrity of ecosystems. If I look at all  the proxies we’ve  dealt with over the history of ecology, it’s actually a really good one. It’s an index  of vitality of an ecosystem.” 

“The Mother Tree Project has done some correlations between biodiversity and carbon pools in the rest of the province. What we find is that the biodiversity of the tree community is tightly correlated with carbon pools.  That makes sense because biodiversity is important to the cycling  of all  the major nutrient cycles that drive our planet.”

“The more diversity you have, the deeper the utility of those resources and the better the cycling of all those resources and the more complete the use of resources by a forest in soils and in the atmosphere.  It goes hand in hand, it makes sense and other studies around the world have also found that tree  diversity in general is correlated with carbon pools.”

“If we look at the big indicators across the world, those things in forests that are the most diverse, have also the richest carbon pools and they’re managed using traditional cultural techniques.”  

Bruce Ellingsen: “Do you know any professors at UVic, or SFU, or Royal Roads or anywhere who are actually studying, long-term studies, of other carbon pools and the impact of harvesting on forest?” 

Suzanne Simard: “I’m a professor at UBC and I have the Mother Tree Project and the Mother Tree Network. We have permanent sites that we established over the last 10 years where we’ve tried different harvesting techniques and we’ve been tracking impacts on carbon pools in soils and above ground plant communities and trees.”

There’s also a lot of experiments that have been established over the years in British Columbia by professors at UBC or other universities and in the Ministry of Forests that have a lot of information in them, but they might not have collected carbon pools , but they still exist out there. There are still some beautiful experiments that we can go back to and learn from, using new indexes of productivity like carbon pools and, looking at them  through that lens.”  

Sadhu Johnston: “I was hoping you could talk a little bit about plans for Cortes and plans for the Mother Tree Network. I know you’re doing three centres and that Cortes is going to be one of those. You’ve received some funding to support that work. I know we’ve lined you up at the Cortes Island Academy, so high school students  will be working with  your university students and so maybe you could just talk a little bit about  where Cortes fits in with the Mother Tree Network, and some of the upcoming plans. 

Suzanne Simard: “Thank you Sadhu. The Mother Tree Project started in about 2015, and we have nine experimental forests established in the Interior of the province, in Interior Douglas Fir, and one Coastal Western Hemlock Forest near Malcolm Knapp Research Forest (in Maple Ridge). That’s been our springboard for developing the Mother Tree Network, which is working more closely with communities to apply our learnings from the Mother Tree Project to support communities as they try to work with their forest to protect remaining old growth, to restore planted forests that are underperforming, including on Cortes Island (we found that your older plantations are not in great shape), and to also work with new ways to manage primary and secondary forests.” 

“So instead of clear cutting – what could we do differently that would protect carbon pools, protect biodiversity and also maintain regenerative capacity of the forest?”

“We have received funding from many sources, but one principal funder who is contributing more than the others and made the decision to establish three pilots in the coastal forest. We know that  in our era of climate change,  these are the richest in terms of biodiversity,  carbon pools and cultural values, really, because there’s more people living along the coastal ecosystems.” 

Some of the oldest First Nations communities with their great cultures are  trying to adapt to climate change and self-determination. So we’ve decided to work with three communities. One is Haida Gwai, one is Maʼa̱mtagila in the Kwakwaka’wakw Nation, and one is on Cortes Island  with you.” 

“They’re all going to be unique, but there are some similarities.”

“This era is a great transition opportunity for moving away from a timber focused economy to more of a wellbeing, or economy which carbon can provide a transition tool.” 

“We need to find out in each of the pilots:

  • What remains? 
  • What’s happened? 
  • And as we’re doing this, try to figure out how can we help innovate management of the forest – the planted forest, the old growth forest. 
  • How can we innovate so that these forests are resilient and productive and big carbon sinks moving forward. 

“Each place will be different of course, because, they’re different ecologically and they’re different socially.”

“So we think that we’ll follow up on those observational studies of what is there with more experimental studies trying different things.” 

“On Cortes, as you mentioned, Sadhu, we’re also going to be working with the Academy and working with students. So we are going to start sometime in August, sampling forests for carbon pools and so on, using our usual approach, but incorporate the students into our teams. We can teach and work alongside them, collect data, analyze that data with them, and interpret that data with them. Then figure out what they think and what we all think for moving forward.”  

“How can that inform what we’re going to do in the future?”  

“That’s a nutshell of what we’re planning to do. Just really be in there with the students and the people working hand in hand.”

Mark Lombard: “Some of the most interesting conversation and exciting discussion I’ve been a part of in the last two years in community forest has been with yourself and your team and the students. I really look forward to contributing to the conversation for our project plan.”

“What I wanted to ask you about, within your presentation you mentioned the ‘sweet spot’ twice and I wanted to hear a little bit more about the sweet spot?”

Suzanne Simard: “I use that word sweet spot just to say, if you’re trying to balance all values on one piece of land, so regeneration, diversity, carbon pools that if you had to pick one thing, probably  a 40% cover would do that thing, but  it’s compromising everything at the same time.  I really believe based on my extensive experience in forestry, that you shouldn’t be doing the same thing anywhere. So that is just one option. You would want to have areas where you don’t affect the forest at all because you’ve got rich carbon pools and some species will only occur in these intact forests.” 

“On the other hand, in some areas where you’ve got bigger fire risk or drier areas where you know that the forest is going to change quite quickly (because climate change is happening fairly rapidly in certain areas more than others), you might want to open up forests a little more to encourage more Douglas Fir. It really needs to be thought through very carefully that there is no single answer to any of this, but we can inform ourselves of what we can expect through these kinds of studies and be better planners of the landscape in that way.

Anonymous: “I just wanted to ask if in your study you had a chance to see how the invertebrate diversity shifted at different stages of retention?” 

Suzanne Simard: “Unfortunately we weren’t able to do that but lots of other people have been looking at this and I’ll just share something I learned today. I’m on Salt Spring Island with the Mother Tree group and Briony Penn was  looking at snails and slugs, something I don’t know that much about. She was saying that  what they’re finding is that these higher retention levels, so 60% or more, conserves those invertebrates more than the lower retention levels.”

“I would think all the invertebrates that depend on dead wood, those higher retention levels are going to conserve those dead wood legacies better than, for example, clear cuts or low retention. When you get machines in there, you really break up that coarse woody debris. You break up that habitat and really we find a huge loss of highly decaying wood the more intensively you manage the forest. You would see losses of those invertebrates.”

Noba Anderson: “I know that it was the Co-op that invited you to do this work and great gratitude to the call for that. I’m just wondering if you have been able to present some of your initial findings to the partnership and how that’s been received. Perhaps there’s members here today who are part of the partnership who might be able to speak better to that because ultimately it’s the partnership that makes management decision.”

Sadhu Johnston: “Suzanne, would you like me to jump in?” 

Suzanne Simard: “That would be great, Sadhu.” 

Sadhu Johnston:  “Today is actually the first time that any of us have heard the results. We are looking to get the results and, continue to keep the partnership in the loop and involved and enthusiastic about the work, particularly as Suzanne and the team’s role deepens on Cortes. So I’d say we’re still early stages.” 

Suzanne Simard: “We have a draft report and we’re just doing some final edits on it this week and we’ll be able to  distribute it probably  in a week or two.”

Aaron Ellingsen: “So are there any more questions in the room?”

John Preston: “I don’t know if this is the appropriate venue, but given all the careful work that the Foundation is doing, where is contact with Mosaic in this whole dialogue of Cortes’s ecosystem at the moment? Because no matter how much care we take of available land, that will be a very big fly in the ointment, perhaps at some point. Is that a question for here?” 

Carrie Saxifrage:  “I think it’s a really great question and it’s probably not a question for here, unless Suzanne wants to answer it, but I think it’s beyond the purview of what we’re trying to address here.” 

 Suzanne Simard: “I’ll defer to Sadhu on this.”

Sadhu Johnston: I’m on the Children’s Forest board as well, and through that we’ve been engaging with Mosaic. Then other projects that I’m involved with, have been engaging with Mosaic. I know they’re in the process of evaluating what they’re doing on Cortes, and more broadly.” 

“So I do think the point you’re making is really good, which is as  the Mother Tree Network report is done and that work is moving forward,  it would be really good for us to engage with them and try to collaborate on that. Both to share the findings, but for them to know that the community is really paying attention and then has perspectives on how they would operate on Cortes.”

“So I think that’s a really good idea  for us  to share this work with them. So thanks for bringing that up, John.” 

“I’ve got another question for Suzanne. For the three pilot areas, are you envisioning that each one would have a staff person in that community or one staff person that would be  coordinating things between those places. How are you going to be involved in the local communities in terms of  boots on the ground – consistent participation  in forums and sharing work and whatnot.” 

Suzanne Simard: “We do anticipate having at least a part-time person  leading each pilot and we’ll put resources as needed through for each one as we go on.”

“At the beginning, there will be  at least a part-time person  leading  the charge on Cortes. We’ve just developed the Mother Tree Network Society,  which is a nonprofit and we’re seeking charity status right now.  We’ll be  advertising for an Executive Director which will also help in the governance of the three pilots, so we should be amply led.” 

“We are a network right now  of about at least about 10 of us, that have different areas of expertise and then we have a crew of at least a dozen students.  We also want to hire local people in each pilot area to help do the work in combination with our students, which on Cortes I think will mean working with the Academy and those students.”

“I’m going on and on with my answer, but we will have at least a part-time coordinator on Cortes who will be then under the direction of our Executive Director.” 

Sadhu Johnston: “I just wanted to signal to people in the room, there’s a future job opportunity there for people that really care about this topic.”

Aaron Ellingsen: “Thank you so much, Suzanne.  I think some of our board members that have had more back and forth with you over the last year and a half since the Mother two Network started working on Cortes. For me, this is the first time that I’ve had a chance to hear some of your results. Really exciting stuff and also exciting to hear that you’ll be back just in a couple of months, and that you’ll be working with high school students.”

Top image credit: Dr. Suzanne Simard – Photo by Jdoswim (Own Work) via Wikimedia (CC BY SA, 4.0 License)

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