Come Rain or Shine

Managing for Change: California’s Giant Sequoias

April 06, 2022 USDA Southwest Climate Hub & DOI Southwest Climate Adaptation Science Center Season 3 Episode 4
Come Rain or Shine
Managing for Change: California’s Giant Sequoias
Show Notes Transcript

How are extreme events transforming sequoia forests in the western US.? And what are land managers doing about it? Dr. Christy Brigham, Chief of Resources Management and Science at Sequoia and Kings Canyon National Parks, and Dr. Joanna Nelson, Director of science and conservation planning with Save the Redwoods League, visited with us to share their knowledge and experiences working to conserve these iconic trees. Image credit: Pixabay

Relevant links:
Sequoia and Kings Canyon - National Park Service
Save the Redwoods League
Giant Sequoia Lands Coalition

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Come Rain or Shine affiliate links:
DOI Southwest CASC:
https://www.swcasc.arizona.edu/
USDA Southwest Climate Hub:
https://www.climatehubs.usda.gov/hubs/southwest
Sustainable Southwest Beef Project (NIFA Grant #2019-69012-29853):
https://southwestbeef.org/ 

[00:00:00] Emile Elias: Welcome to Come Rain or Shine podcast of the USDA Southwest Climate Hub 

[00:00:05] Sarah LeRoy: and the USGS Southwest Climate Adaptation Science Center or Southwest CASC. I'm Sarah LeRoy, science applications and communications coordinator for the Southwest CASC. 

[00:00:17] Emile Elias: And I'm Emile Elias, director of the Southwest Climate Hub.

Here we highlight stories to share the most recent advances in climate science, weather and climate adaptation and innovative practices to support resilient landscapes and communities. 

[00:00:34] Sarah LeRoy: We believe that sharing some of the most innovative forward thinking and creative climate science and adaptation will strengthen our collective ability to respond to even the most challenging impacts of climate change in one of the hottest and driest regions of the world.

The contents of this podcast are for informational purposes only and should not be interpreted as endorsement for any of the products, technologies, or strategies discussed. 

[00:01:07] Emile Elias: Last month, we talked with Dr. Craig Allen and Dr. Nate Stephenson about ecosystem transformation in the Southwest US with the focus on forests in New Mexico and California.

Dr. Stephenson spoke about the transformation taking place in Sequoia forests, especially after large fires in recent years. Today, we're going to focus our discussion on the transformation taking place in Sequoia forests and the steps people are taking to address this challenge. Dr. Christy Brigham is the chief of resource management and science at Sequoia and Kings Canyon National Parks. Also joining us is Dr. Joanna Nelson, director of science and conservation planning with Save the Redwoods League, a non-profit organization with the mission of protecting and restoring coast Redwood and giant Sequoia trees. Welcome. Christy, could you start us off with a description of the forests you manage and then talk about the changes you've been observing in recent years.

[00:02:11] Christy Brigham: Sure. I'd be happy to. Thanks so much for having us. Since this is a podcast I'll, I'll wax poetic a little bit in the beginning, for those of you that haven't had the pleasure of walking in a giant Sequoia forest, they're really fabulous. Everyone, even people who aren't tree fans love these trees and notice these trees because of their great size, their immense age, and their presence on the landscape. They're really huge. 10 to 30 feet in diameter. It takes many, many people to give a Sequoia a hug and they can live 2000 to 3000 years. They are the largest non clonal living organism on earth. When you walk among them, you really feel their age. Their canopies are very quirky.

They're all funny shaped. And they have like one big arm. And you can tell they've been struck by lightning and survived dozens, if not a hundred previous fires. They're an international destination. So in, in the parks that I work for and manage, we manage 37 groves which is almost half of the total groves there's around 70 groves.

So it's actually a little more than half, depending on how you count. And about 10,000 acres, including the second and third largest Sequoia groves on earth. Giant forest and Redwood mountain. They're really spectacular and I hope everyone gets a chance to come and visit them. Recently, we have seen some really alarming changes in these groves.

As I mentioned, the trees are extremely long lived. That means they're very resilient. They've survived a lot of changing conditions in the past, but recently at the tail end of the climate change driven, hotter drought that we had in California, which was extremely severe in the Southern Sierra Nevada.

We started to see some worrying things. We saw large Monarch trees that shed huge amounts of needles up to 70% of their canopy, in response to that drought. We had individual Monarch sequoias that died at the end of the drought, we think by beetle attack by Western Cedar bark beetles, which has never been previously observed in a hundred years of studying these trees.

And then since 2015, we've had an alarming escalation of loss of these trees in extreme wildfire, which has never been recorded at this scale. These trees are extremely fire adapted. They have survived dozens of previous wildfires. They actually need fire to regenerate. They have extremely thick bark.

Their branches are 200 feet off the ground, but in recent fires we've lost 20%, of the entire population of large sequoias. 

[00:05:04] Emile Elias: And do you have an estimate of what it is about those more recent fires that has led to that? 

[00:05:10] Christy Brigham: Yes. We think it's a combination of factors having to do with previous management.

So we've had a lot of fire suppression in the Sierra Nevada to protect communities and to protect those forests, which was a mistake. They actually need fire to thin the trees and get regeneration and maintain drought resilience. So a combination of fire history that has, I mean, fire suppression, which has made the forest more dense.

And then the drought killed a lot of trees, which increased fuels and drove severe fires. And then we've had droughts continue to have droughts, which has resulted in dry fuels and extreme fire, mass fire with wildfires that generate their own weather and have these crazy flame lengths a hundred to 200 feet high and have really damaged portions of our landscape.

[00:06:08] Emile Elias: Thank you. And Joanna, is there anything you'd like to add about the forest where you work or changes that you've seen? 

[00:06:14] Joanna Nelson: Yeah, I'd like to thank you also for having us. And just note that Christy gave a really comprehensive answer and I'd like to emphasize this major uptick in wildfire, wildfire area, and intensity severity since 2015.

And in particular in a 2020 fire. So the Castle Fire of 2020, and then two fires in the fall of 2021. Within that major uptick from 2015, with those two years of fire, we've lost 20% of giant Sequoia. So that was a 14 month period. And it's 20% of giant Sequoia on the planet. So the changes are right in our face.

And everybody who's already working hard in conservation is redoubling our efforts to work on protection of these ecosystems. 

[00:07:12] Sarah LeRoy: Thank you, Joanna. And thank you Christy for laying out really the challenges that we're facing with managing these forests. In fact, I want to switch gears a little bit to managing. So Christy, what are some of the things that the Park Service is currently doing to address these changes that are so detrimentally affecting giant sequoias?

[00:07:31] Christy Brigham: That's a great question, Sarah. And, and you highlight in your question the most important point, which is that in order to respond to these changes and this crisis, this ecological crisis. We need to actively manage these forests. They did and have existed for thousands of years on their own without our interference, but because of fire suppression and climate change, they need active management.

And so here at Sequoia and Kings Canyon, we're doing several things. We have, we're working with our partners to address Sequoia's range wide in the giant Sequoia Lands Coalition to prioritize areas for treatment. Here in Sequoia Kings Canyon, we're doing restorative thinning of one of our second growth groves that's overly dense. We're also doing prescribed burning of some of our groves that have fuel accumulation to reduce that fuel accumulation and get regeneration. And then in some of our severely damaged forests, specifically Board Camp Grove and perhaps Redwood Mountain Grove, we are undertaking projects to actively replant sequoias in some groves where the majority of the living trees have been killed by fire.

[00:08:49] Sarah LeRoy: Thanks, Christy. Joanna, so what is the role of Save the Redwoods League in this, in managing these forests and how has your organization been taking action? 

[00:08:59] Joanna Nelson: Thanks for that question. Save the Redwoods League works to protect and restore coast redwoods and giant Sequoia throughout their entire range. So for coast redwoods, that's from Big Sur area in California north to the California-Oregon border on the coast and giant Sequoia on the Western slope of the Sierra Nevada. So we work in collaboration with our partners and this fairly new Giant Sequoia Lands Coalition, which is every entity that stewards giant Sequoia in any way that manages them. 

So the Tule river tribe as indigenous stewards, federal and state agencies, and Save the Redwoods as both a non-profit partner and we as a land trust purchase properties that still need protection that may have been in private hands. And one example is the 530 plus acre property in Alder Creek Grove that we are stewarding similar to what Christy said with selective thinning, with prescribed fire, with responding to what's happened.

So doing that selective thinning in the areas that didn't burn in the Castle Fire, and dealing with the really comprehensive destruction on the north and south end of the Grove, where the Castle Fire killed mature trees, killed cones and entire seed crops. So there's a replanting there. Our long-term goals are to ensure the health of the forests and connect people to them wherever possible.

And we're consistently working with indigenous native and tribal communities and nations. And I want to just, again, add to what Christy mentioned that we've had a hundred plus years of federal policy of fire suppression. We have tens of thousands of years before that of indigenous stewardship and tending of these groves.

So there has been, these trees evolved with low to moderate intensity fire, just like Christy said, they need it to reproduce. And there has been both lightning start fire and indigenous tending, using fire as a tool. So it's a fairly recent and really exacerbated problem with excluding fire on the landscape, having increased fuels and then changing warming and drying through climate change and climate disruption.

[00:11:39] Sarah LeRoy: Thank you, Joanna. So you were both co-chairs of the science group for the new Giant Sequoia Lands Coalition. So Joanna, I was hoping maybe you could tell us a little bit about what the coalition is doing for giant Sequoia. 

[00:11:55] Joanna Nelson: The coalition aims to continue the work that we're all doing of protecting and restoring giant Sequoia ecosystems and to advance as quickly as possible, the pace and scale.

And one way we do that is by looking at what is it that we can best do together, right? Every agency or entity has their mandates, their jurisdiction, the good work they're already doing. What is it that we can do as we help each other. And I'll turn it to Christy to add to that. 

[00:12:25] Christy Brigham: Thanks, Joanna. That was really comprehensive.

I don't have much to add. We're just working at the intersection of scientists and managers to address these changing threats and conditions. Beetles, wildfire, climate change. How can we learn and adapt our management to protect and preserve these amazing trees for future generations? 

[00:12:48] Emile Elias: Yeah, building on that.

We're talking a bit about forest transformation and management. In our previous episode on forest transformation, we discussed assisted migration and how it can be used as a way of managing forest change. So Christy, has the park service been thinking about using assisted migration with giant sequoias?

[00:13:09] Christy Brigham: We have been thinking about using assisted migration with giant sequoias and exploring that and talking to the public and drafting some potential plans was actually really high on my work plan until beetles started eating my trees and wildfires started burning them up in the thousands which took precedence but all things in life seem to be circular.

So now we're coming back to that, in that, with these recent fires, it actually makes it incredibly urgent to decide around a couple issues around climate change. One is, assisted adaptation. This idea of using genotypes that are better adapted to what we think the future climate might be. So, not just using the seeds from a particular grove, but including seeds from other groves that are currently growing under hot dry conditions.

So we actually have a pilot project proposed to use some different genotypes in a subset of our board camp restoration. And then the second piece of that is looking at assisted migration. So we have a lot of area that burned at high severity, where we need to consider restoration. And as part of that, what trees will we plant, where, and do we want to consider moving some sequoias uphill or into areas where we expect the snow to persist into the future as an assisted migration experiment. And that would fit within the Park Services general approach to resist, accept, direct response to climate change where assisted migration would be a form of resisting the loss of Sequoia's under climate change.

So it is something that we're actively considering, especially in the context of post fire restoration. 

[00:15:14] Emile Elias: Thanks Christy. Joanna, did you have something you'd like to add? 

[00:15:17] Joanna Nelson: Yeah. I'd like to underscore the good science basis for that work for those choices in assisted adaptation and assisted migration and acknowledge, there's also values and societal choices at the Save the Redwoods League.

We are currently picking seed mixes to replant in Alder Creek Grove in the section that is League property. And just like Christy said. So we're looking at seed mixes from seeds that grow as they do in the, in nature on the trees that may be more drought adapted or arid adapted. So, our seed banks will always include that from the local grove.

And we are working with a conservation geneticist to look at including seed from more Southern groves with wide genetic diversity and a different tactic, more of a regional focus. So we're doing that work right now. This month, choosing seeds to have grown up in the nursery and the League has also initiated and funded a five year research program to map the genome of both coast Redwood and giant Sequoia.

And that foundational science work is done, completing the sequencing of the genome. And there are more steps between research and conservation action to know what traits can respond to the climate changes that we're seeing for giant Sequoia, again, to protect these trees into the future. 

[00:16:51] Emile Elias: Thanks Joanna.

So you've both talked a bit about this onslaught of different threats and trying to prioritize what needs your attention at different times. And also talked a bit about restoration actions and even thinking about the genome and, and the seed mixes that you just mentioned, Joanna. So I'm wondering, how you decide what restoration actions to implement and what that process looks like and what factors into it, if there's anything we missed and we'll go ahead and start with Christy. 

[00:17:24] Christy Brigham: It is very difficult to prioritize and choose actions in the face of uncertainty. And there's a lot of uncertainty about future wildfire behavior, future climate changes, future biotic interactions as the climate changes.

But we do have a lot of tools at our disposal. And I mentioned this concept of resist, accept, direct. And I think Dr. Mark Schwartz will be on the program later. Mark was my thesis advisor and is a good friend and he has developed, with a lot of partners, a really great tool for evaluating the risks of assisted migration.

And we also are working in partnership with the US Forest Service, who has developed a really great tool to prioritize burn landscapes for restoration. That very explicitly considers areas where wildfire was beneficial, which is a lot of area. We've had many, many groves burn in wildfire. Many of them, we had beneficial effects.

So it considers areas where there were beneficial effects, areas where there were negative effects, and the potential for those restoration investments to be lasting. So under climate change, given slope, given what we think about precipitation, where should we make those investments that are likely to last and, and aid and benefit sequoias as they respond to these changes?

[00:18:55] Joanna Nelson: Great. And I'll add to that really good answer with how do we know what to do. We assess what we know in the scientific literature and reporting, and by definition, that's a snapshot. What do we do right now? What's our level of certainty? What does that mean? Where do we have more of that uncertainty? And then making decisions across science and management groups and appreciating people like Christy, who are scientist managers, there are all kinds of words for it.

I love my work in science to action. Right? So assessing, here's what we know. We have high confidence. Okay. We're gonna go forward with that. Here's where we have more uncertainty and we're going to use this as a proxy or do these experiments and then the opportunity to have different ways of knowing and different forms of science.

So I'm non-indigenous, I'm not speaking for anybody indigenous and it's been my honor to work with different indigenous groups, land trusts, and native stewardship core groups on the landscape to think about what do you see and how do you respond? And that we have a lot of different ways and different sciences.

[00:20:20] Emile Elias: Great. Thanks Joanna. So another question for you and we, we like to tell stories and share examples on our podcast, and this might be a long shot because there haven't been that many assisted migration projects. But I'm wondering if you have any stories or examples about factors that have either hindered or bolstered assisted migration projects in the past.

And we'll start with you Christy. 

[00:20:46] Christy Brigham: We haven't initiated any assisted migration projects to date, but I will say there are a couple factors with giant Sequoia and I spend a lot of time talking to different groups about giant Sequoia. School kids, college students, the community, the press, public meetings.

And one of the things that giant sequoias have going for them is that people love them across the board. And that means that we are willing to consider what might be considered an extraordinary measure to keep these trees on the landscape. So that's a huge benefit and we have generally received positive responses.

When I talk, when I tell people about what's happening with Sequoias, people wanna fix it. They wanna know how do we fix this problem and they're okay if part of the solution means some experimental planting. The other more ecological biological benefit of giant Sequoia as a pilot experiment with assisted migration is that they live a long time and it takes them quite a bit of time to make new seeds.

So you've got about 30 years to figure out whether you made a mistake, which as a scientist manager, I really appreciate. So if we do move forward with an assisted migration project where we actually move trees outside of their native range, we'll have 30 years of monitoring to get a feel for, wow, is this going badly or is this working the way we want it to?

And finally, Because people do love them. They've been planted all over the world and in California, outside of their native range. So we have some clues and indicators of how that might go and what factors might affect them, were we to undertake that? So some clues there, in the stories of people and giant sequoias. 

[00:22:52] Emile Elias: Great. It's like spontaneous common garden studies happening. Excellent. Joanna, is there anything you'd like to add?

[00:23:00] Joanna Nelson: Only that there are these spontaneous common gardens. And then there are experimental common garden studies where seeds from different groves are planted in the same place. So with this different evolutionary history adaptation, local climate, now they're all growing in this same hydrologic regime climate conditions, and we can see how they grow differently.

So there are some, again, really helpful experiments that are, some of them are 30 years in. Some of them are two years in, that give us a window on how this would go. 

[00:23:35] Sarah LeRoy: Both of you have really shown what an iconic species giant sequoias are. And so I imagine that when managing this iconic species, I mean, Christy, you said this, everyone is watching what you do, and everybody is engaged and everybody wants to know what's going on and they wanna be a part of it.

So I imagine it can really help to have public support in your management efforts. And I think you touched on this by, you know, all of the activities that you do with the public and policy makers, but how have you been able to get the public on board with your management and restoration plans?

Or have you have there been times when the public is just not happy with what you're doing and how do you deal with that? 

[00:24:20] Christy Brigham: That's a great question. And, and I think I'll answer it in a couple parts. The good. Every, you know, everything is a double edged sword, right, Sarah, and the fact that people love these trees is a benefit.

And it also means they're concerned, which I totally understand. So the ways in which it has gone, well, I talked briefly about before, but the Park Service has a long history of very careful management of the resources that were entrusted to us. And since the sixties, at least we've had a management policy where we really prefer to let natural processes unfold.

We try not to interfere. That history has built a very trusting relationship with the public. The public loves their national parks. In general, they trust that we're working hard to do our best for these ecosystems, that we don't have any hidden agendas that we care about these places as much as they do.

And that's amazing. I so appreciate that. And I so appreciate the public support and care and value of these places. So that has been a big benefit to us. People love sequoias. They in general, uh, support our prescribed fire program in general. They trust us and are interested in what we might do to keep this species on the landscape.

The part that's a little bit more difficult is that the public can think of nature and national parks as a place where people don't take action as a place where nature takes its course. And we are realizing that people are part of this environment. And we, Joanna has talked about tribal stewardship, indigenous stewardship, and we need people to be part of this stewardship. And that means taking an active role. And it means doing things like restorative thinning and prescribed burning and planting, and maybe even assisted migration. And because people love these trees so much, and they have certain ideas about how national parks function they can become alarmed about some of these more active management approaches. I understand, I love these trees too, and I want what's best for them too. So I'm happy to engage in that dialogue and explain what we're seeing and the data and the changes and our careful approach and why we're proposing what we are proposing so that we can come to agreement about our values and the needed next steps to preserve those values and things like giant sequoias.

[00:27:06] Sarah LeRoy: Thanks Christy. That's really great to hear. And Joanna, I imagine you have a lot to add to this as well. So, has Save the Redwoods been able to help with gaining public support and what approach do you find that generally works best when you're trying to foster public understanding whether it's decision makers, the general public, understanding of the need for certain practices.

[00:27:30] Joanna Nelson: Yes. Thank you. I really appreciate Christy's willingness to engage so many communities and so many questions. And Save the Redwoods League is certainly able to engage the public and get the word out again with this shared experience of the beauty and awe of being in the giant Sequoia. So our members and followers know, that's what we're here for. And that's what we're moving forward and count, count on us and our voice. We've been proactively getting the word out to our tens of thousands of members and followers, as well as working with the media to help them report out this story in their channels.

So both the story of these incredible forests, and of alarming changes that we're seeing right now. The resulting media coverage and response has been extraordinary. It's literally a tenfold increase in the reach of these stories. And again, I had the opportunity to be out mid-November of 2021 with a media outreach event, where Christy led our get out in the field to Redwood mountain Grove to see, both the full destruction from wildfire on the south end, and the Grove where the trees were alive. So ready to get people really out there to see it. And that's really effective. We work on education, helping people understand how did we get to this point? How did we get to this point with forests that are too dense?

That are overcrowded, the role of fire exclusion, the role of climate disruption, and again, with what they can do to help with what active management means and what forest scientists, managers, and fire managers are doing. So those have all been really effective tools. Visuals are always compelling, maps, infographics.

Bringing people in. And again, best of all is, is being out on these landscapes and walking through them to experience what's going on with the trees and the ecosystem. We also are receiving outreach from elected officials who are interested in developing the legislation and the policy to protect these trees because they understand that it's an emergency and that the scientists and managers, for example, in the National Park Service with indigenous tribes who steward sequoia groves, that there are people on the ground who know what needs to happen next, and that we have needs around funding and where that funding gets directed around a skilled workforce with a lot of different ways of managing land and using prescribed fire and cultural burning. And again, with policies that let us go forward and do the work in a timely way and not get strung up on, for example, paperwork that takes a couple years when we have another summer fire season coming in four, five, six months. 

[00:30:41] Sarah LeRoy: Thanks Joanna. So we like to end each of our episodes on a hopeful note and thinking about the future. And so Joanna, I'd like to ask you what gives you hope for the future when thinking about managing for this transformation that we're seeing in Sequoia forests.

[00:31:01] Joanna Nelson: I have a lot of hope around intergenerational action and everybody bringing their skills, wisdom, energy. And also what I love about that is it's different than piling everything on the youth will save us, right on like the teens will hold everything. So I love intergenerational action. I get a lot of hope out of doing the work that I do in the communities that I'm in, right.

That feeling of working on it. I get hope out of working on it because armchair hope doesn't show up for me. And I have a lot of hope as I've mentioned that, dominant culture is doing less marginalizing and shoving to the edges and more listening to sovereign indigenous native communities who have always been here and still are doing the work and the tending.

And there is more exchange and listening and collaborative action. 

[00:32:04] Sarah LeRoy: Christy. What gives you hope for the future? 

[00:32:07] Christy Brigham: Very similar to Joanna. I also have a lot of hope and for me, it comes from three primary areas. The first is the trees themselves. They are tough. They are survivors. They have been here through previous droughts, previous warm spells, previous cold spells.

They migrated in response to previous climate change. I feel like if we could just stop kicking them in the teeth, they, they would be fine. So if we could just stop burning them down and slow the pace of climate change they'll, they'll survive. They are very tough. The second source of hope for me is very similar to Joanna and it is, I get I get, annoyed when with the whole, oh, climate change, the youth have to solve it. It's not true. There's so many of us working so hard right now to get the knowledge and take the action to set up our amazing youth who are committed and care. And really want to address this. So along with our tribal elders and our tribal partners, we are trying to set the future generations of sequoias and people up for success.

And finally, very similar to Joanna. I really like what Rebecca Solnit says about hope, which is that hope comes from acting in the face of uncertainty. Yes, it's uncertain and how do we deal with that? By taking action, by slowing the pace of climate change, by reducing wildfire severity in Sequoia groves, by trying approaches like assisted adaptation and assisted migration.

So we take action together for our values in the face of uncertainty to hopefully get the future outcomes that we want, which are healthy forests, healthy communities, healthy people, all living together. 

[00:34:06] Sarah LeRoy: Wow. What an amazing way to end this episode and Emile and I both appreciate you being here with us today to talk to us about this iconic, beautiful species.

So thank you very much. I'd like to just add Christy mentioned that Dr. Mark Schwartz will be with us on our next episode to talk more about assisted migration in the National Park Service. So thank you.

[00:34:32] Christy Brigham: Thank you all so much for everything you're doing to help people understand climate change and how we can respond.

[00:34:39] Joanna Nelson: Thank you so much. It's such a pleasure to be here today.

[00:34:45] Emile Elias: Thanks for listening to Come, Rain or Shine, podcast of the USDA Southwest Climate Hub 

[00:34:50] Sarah LeRoy: and the USGS Southwest CASC. If you liked this podcast, don't forget to rate or review it and subscribe for more great episodes. A special thanks to our production crew, Skye Aney and Reanna Burnett. If you want more information, have any questions for the speakers, or would like to offer feedback, please reach out to us via our websites.