Jacob Margolis 0:00
[wind blowing through trees] There's this one spot high up in the Sierra Nevada mountains in California, where for over 2000 years, you'd come face to face with a giant- [music in] as wide as a bus is long, almost as tall as a football field turned on its side, alive since before Ancient Romans broke ground on the Coliseum, and soft enough that if you gave it a hug, it'd feel like it was hugging you back. Its name: General Sherman- a Giant Sequoia, a tree that's one of the largest on planet Earth.
Christy Brigham 0:39
That's the Sherman tree. This is actually the best view because once you get up close, you can't see the whole thing.
Jacob Margolis 0:47
Walk up to its base and it's the equivalent of being a baby chick, standing at the feet of Shaquille O'Neal.
Christy Brigham 0:54
What you can see is a really fat trunk that's red, and it goes straight up. And then as you get about 100 feet up, it breaks off into several really big branches. And those branches are themselves are bigger than most normal trees.
Jacob Margolis 1:14
This is Christy Brigham. She's the head of Resource Management and Science for Sequoia and Kings Canyon National Parks, which are home to General Sherman. And we should note- the land the Sherman tree is on used to be home to tribes including the Mono, Yokuts, T¸batulabal, Paiute, and Western Shoshone before they were all forcibly removed. The history of the tree is a bit murky, but we do know that it was named after a guy who was a general in the Union Army during the Civil War. Later he led violent campaigns against Native Americans.
Christy Brigham 1:45
But it was owned before that by a colony, like a socialist colony that was trying to have uh idyllic logging and share the profits and they called this the Karl Marx Tree. [JM laughs] But then when the p- [CB laughs] when the government got it, you know, it changed the name.
Jacob Margolis 2:03
For thousands of years, General Sherman has lived in a Sequoia grove with a whole bunch of its buddies. Just hanging out, cleaning the air, fighting climate change as trees do. [music out] But in September 2021, General Sherman faced a new kind of threat. [music in]
KPIX CBS SF Bay Area News Announcer 2:22
Two separate lightning sparked fires have now merged into the KNP complex, marching towards some of the oldest Sequoia groves on the planet.
Jacob Margolis 2:30
Two fires had combined into an even bigger fire. And that fire was marching straight towards General Sherman and all its friends. Christy and others knew they had to get in there to clear debris from around the base of Sherman to keep it from catching on fire.
Christy Brigham 2:44
On a Monday, I was trying to organize a militia, like, a bunch of volunteers from resource management, who could run up here and rake around these trees that we thought were at risk. And we were all ready, and we were texting, and I was like, Okay, I've got 20 people! We're getting the rakes! We're ready to go!
Jacob Margolis 3:05
They had their game plan. All they needed was the green light. [music out]
Christy Brigham 3:11
And then I got a call and they're like, it's not safe. You can't go. And I just, [crying] I cried. And so I was really upset like, like I am now telling you, um because you feel like you've failed, right? The window to do something to protect the trees has passed.
Jacob Margolis 3:29
Still, Christy hoped and waited. [music in] The crazy thing about all this is that we really shouldn't have to worry about Giant Sequoias burning because they're adapted to living with fire. But now, they're getting wiped out left and right. And extreme fire is decimating many of our forests all across the Sierra Nevada. But there is hope. In the first episode, we talked about how overwhelmingly scary and awful wildfires can be. Now, we're going to get into what this new age of wildfire is doing to our forests. We're going to get into the science of why we're seeing such destructive wildfires. And we're going to do that by taking a deep dive into one of the most remarkable tree species on planet Earth... Giant Sequoias. This episode... why trees that have been built to handle fire are now being destroyed by it, and what we can do to save them. This is The Big Burn. I'm Jacob Margolis.
Jacob Margolis 4:40
[footsteps] [car starting and driving off] Back in the early spring, I rented a car with four-wheel drive, picked up Senior Producer Sophia Paliza-Carre, and we set out for Giant Forest. We pulled over at the Visitor Center to pick up Christy Brigham. She was decked out in U.S. Forest Service clothes, just different shades of green from head to toe.
Christy Brigham 5:14
So have any of you been here before?
Jacob Margolis 5:17
Hold on. Don't talk to us yet. [CB laughs] Let me get set up. Don't say anything really awesome. [CB laughs] We're not ready.
Sophia Paliza-Carre 5:28
Okay, I'm rolling.
Jacob Margolis 5:31
What is the meaning of life? [CB and JM laugh]
Christy Brigham 5:34
That's a tough one. Yeah.
Jacob Margolis 5:35
[driving ambi] We drove up a windy road, scraggly dry brown looking Chaparral and Oaks, giving way to taller evergreen trees as we climbed higher and higher up the mountain.
Jacob Margolis 5:48
Alright, so I need you to narrate where we're going.
Christy Brigham 5:51
Okay, so we're at a thousand feet elevation, and we are driving up the General's Highway, and we're gonna go up 5000 feet in elevation, and this is one of the steepest parts of the Sierra Nevada. So this much elevation gain crammed into such a short distance is pretty unusual and really different.
Sophia Paliza-Carre 6:12
We're up high!
Jacob Margolis 6:13
Anyone feel like they're gonna puke? Everybody doing ok?
Sophia Paliza-Carre 6:16
A little bit, I'm not gonna lie. [everyone laughs]
Jacob Margolis 6:21
Even from inside the car, I could feel the air getting cooler as we climbed. Soon, we were driving past small patches of dirty snow on the side of the road, and the trees started to get bigger and bigger. I thought the Incense Cedars were impossibly large, but then, the Giant Sequoias came into view.
Christy Brigham 6:40
Their canopies are not like the drawing you make of a Christmas tree that's pointy with little spiky pieces. They're like kooky broccolis with one fat arm, and they're so much bigger than anything else. They're the spokes trees of the forest to speak for all the trees that nobody notices.
Jacob Margolis 6:59
They're pretty overwhelming. Like I, I can't imagine the first people to come across uh, Giant Sequoias- what that, that feeling must have been like.
Christy Brigham 7:08
Yeah, the native people who lived here knew they were special. And, and the first Europeans who encountered them were blown away and no one believed them. So then they had to of course, cut one down and peel all its bark off and send it back east to a world's fair.
Jacob Margolis 7:24
[car coming to a stop and door closing] They were even more impressive up close.
Jacob Margolis 7:33
[footsteps] So big! [laughs]
Sophia Paliza-Carre 7:37
You really have to lean up.
Christy Brigham 7:40
Jacob Margolis 7:41
Gotta lean, lean all the way back to see all the tops. Wow.
Jacob Margolis 7:45
[footsteps] We followed Christy up a paved path with Giant Sequoia needles crunching under our feet. Like the rest of California, wildfires are a natural part of these mountains. And I was looking around trying to spot the signs. I saw some Giant Sequoias had black marks all over their shaggy red bark.
Jacob Margolis 8:05
There seem to be burn holes, like holes that look like they've been burned in the tree. What- [CB: Yeah.] Do you know what those are from?
Christy Brigham 8:10
Those are mostly places where there were branches, [JM: Okay.] and that's a remnant of the branch. And so one of the things that um, fire adapted trees do is that, as the, as the canopy moves up, they drop their lower branches so that they're not there to carry fire into the canopy.
Jacob Margolis 8:30
This is part of the Giant Sequoia's defense system against fire, and it's actually pretty clever. It drops its old, lower-to-the-ground branches, which stops the fire from climbing into the tops of the trees. Because if they burn so bad that their tops burn too, it often means death. But Giant Sequoias aren't just playing a game of defense against fire. They're so well adapted to it that it actually helps them make baby Giant Sequoias. When a fire comes along, the heat warms up their cones, and lots of their seeds drop to the ground.
Christy Brigham 9:00
So these little oatmeal, tiny oatmeal looking things? [JM: Oh, wow.] These are Sequoia seeds. [music in]
Jacob Margolis 9:04
These could all be...
Christy Brigham 9:10
They could all be baby Sequoias. You can see how tiny this is. It doesn't weigh hardly anything. It's really light.
Jacob Margolis 9:17
Some of these seeds will sprout, but only a few will ever turn into the giants around us. And even though it's rare for one single seed to make it big, it's a process that's clearly been working in this Giant Sequoia Eden. This one spot on the western side of the Sierra Nevada is home to 30 of the largest Giant Sequoias on planet Earth- A place that for thousands of years has had the perfect temperature, the perfect amount of rain and snow, and the right kind of fire, which is what the seeds need.
Christy Brigham 9:49
After you have beneficial fire, you often get carpets of these. 90,000, a hectare, like a dense carpet.
Jacob Margolis 9:58
So this idea of beneficial fire, the kind that these trees have lived with, it's a really important concept for us to understand because on the opposite end, there's bad fire. Bad fire has been killing scores of Giant Sequoias that are thousands of years old. So what's the difference between good fire and bad fire? That's after the break. [music out] [break]
Jacob Margolis 10:36
To learn more about good and bad fire, we met up with scientist, Nate Stephenson, in a different part of the forest.
Nate Stephenson 10:42
Have you all been here before?
Jacob Margolis 10:43
Well, we came yesterday with Christy.
Nate Stephenson 10:45
Oh, where'd you go? [JM: Uh-] Do you remember?
Jacob Margolis 10:47
We went to Giant Forest. Giant Forest, right?
Jacob Margolis 10:52
Nate has a white beard and this air of relaxed patience. He's in his 60s and have spent most of his life studying Giant Sequoias.
Jacob Margolis 10:59
Do you love Giant Sequoias?
Nate Stephenson 11:02
Do I love Giant Sequoias? How can anyone not love Giant Sequoias? I am passionately in love with Giant Sequoias.
Jacob Margolis 11:11
[crunching forest leaves] As we walked along a forest path, we were surrounded by the entire lifecycle of Sequoias on both sides. There were baby trees just starting their journey, and others as big as buildings laying on their sides. For years, this forest was shaped by what we're gonna call good fire. [music in] See, not all wildfires are so hot and violent, that they completely destroy everything. You can have a whole range of intensities that fire nerds would classify anywhere from low to moderate to high severity. What we used to see in this area and in a lot of our forests, was mostly low and medium severity fire. [sound of breeze and crackling embers] Imagine fire, dancing along, clearing out brush and leaves and some trees, and leaving Giant Sequoias and other older trees scorched, but still alive. We used to see these types of fires frequently, and they were good because they cleared out fuel buildup, which means debris that naturally builds up in the forest, debris that would otherwise drive more destructive wildfires. These smaller fires also made room for new trees to grow. [pause] So, if a couple 100 years ago, you flew a helicopter above this forest, Nate says that if you looked down, you would see open patches, like holes in a block of Swiss cheese.
Nate Stephenson 12:39
Most of it would be this green canopy, but every once in a while, you'd find a little hole in that canopy where the fire burned extra hot, where there might have been some logs had fallen over, a big tree had fallen over there and created a pile of fuel. Um, those holes would be maybe a quarter of an acre to sometimes as big as one or two acres. Those were the hotspots for Sequoia regeneration because Sequoia seedlings really need uh, an opening in the forest. They need the bare mineral soil that's exposed by fire. Um, the heat pulse from the fire opens the cones, and seeds rain down, and then they don't have a lot of competition in the middle of that hole. Um, the roots from outside trees can't quite reach that area, so there's extra water available in the center of that opening. And they get a lot of sunlight and boy, do they love sunlight. So it's, it's the sweet spot, you know. So the Swiss cheese view that you would see a few 100 years ago was normal. So there's always little holes getting punched in the forest by fires back then. [music out]
Jacob Margolis 13:47
There used to be this balance of fire. But now, it's out of whack, Nate says.
Nate Stephenson 13:53
Now we're seeing these gigantic areas, you know, hundreds of acres at a time, maybe even a thousand, that burned so hot, all or most of the Sequoias are dead. And um, that we think is out of bounds of the way things worked in the past, so it could be a new phenomenon.
Jacob Margolis 14:13
[wind ambi] Nate took us to a spot where Sequoias once stood. Now it was just a bare hillside covered in ash, the trunks of former giants completely blackened, burned matchsticks silhouetted against the sky. [fire ambi] This is the result of a landscape hit by a lot of high severity fire. Flames that aren't helpfully clearing debris, but growing so hot, and so large, that they're incinerating everything. Looking back, Nate says it was the Rough Fire in 2015 that signaled a big shift in his understanding of what Giant Sequoias had in store.
Nate Stephenson 14:53
It was clear pretty early on that that was the most Sequoias I had ever seen killed in a fire. Um, it still didn't concern me that much, because you can always chalk that up as well, that was a fluke. The real gut punch was 2020 in the Castle Wildfire, because the satellite imagery started coming in, a few drone shots started coming in, and the size of areas in which every Sequoia was killed were just mind boggling.
Jacob Margolis 15:29
[music in] Nate knew it was bad even before the pictures arrived. He could see huge smoke plumes from his deck 30 miles away. There was ash drifting down.
Nate Stephenson 15:40
I could look and identify the tree species and I was going, oh my gosh, here's charred Pine needles falling out of the sky, charred Fern needles. Oh, here's Cedar. Look, here's some Oaks. And I saw Sequoia ash falling out of the sky at my house 30 miles from the grove that was burning, and I knew it was bad. It was um, almost you know, disbelief mixed with grief.
Jacob Margolis 16:06
It meant that the trees' defense mechanisms hadn't worked. That their leaves 250 feet up in the air were burning- what's known as a crown fire.. and... it usually means death. An estimated 10,000 Giant Sequoias died in that one fire. Nate says that over the last two summers, we've lost an estimated 13 to 19% of them. And it's not just the Giant Sequoias. High severity fires have become more common over the past several decades across many of our western forests, sometimes hitting the same areas repeatedly, burning landscapes so intensely it's unclear whether they'll recover to become forests again. And it's left me wondering... why now? [music out] It's complicated, but a big part of the answer is climate change. I reached out to Patrick Gonzalez, a climate change scientist who's been studying this stuff for 30 plus years and has had a special focus on our national parks.
Patrick Gonzalez 17:12
Human caused climate change has doubled the area burned by wildfire across the Western U.S. above natural levels.
Jacob Margolis 17:20
Patrick explained there are a few things going on with climate change. [music in] One is that it's causing more intense heat waves, and two, it's making our droughts a whole lot worse. Like right now, parts of the Western U.S. are living through the worst drought in well over half a century. Everything is super dry. And that makes wildfires worse because dry, hot landscapes burn more easily, which is why we generally see our worst fires here at the tail end of summer. But the other thing is, all this extreme weather has caused a huge die off of trees in our forests- over 100 million of them over the past decade. And dead dry fuel burns really well. And as temperatures get hotter, Patrick says things are gonna get worse.
Patrick Gonzalez 18:07
If the United States and the world, if we don't cut carbon pollution from cars, power plants and other human sources, global temperature could increase by four degrees Celsius, which is like eight degrees Fahrenheit. And under that case, the tree mortality in Sierra Nevada could increase by 50%. So we would see a lot more of those stands of dead trees. Another part of the worst case is a potential tripling of the area burned by wildfire, uh, with no climate change action.
Jacob Margolis 18:51
Forests are a really important defense against climate change because they suck up a lot of carbon dioxide, a greenhouse gas, but because of climate change, more of our forests are burning, releasing carbon dioxide into the atmosphere, making climate change worse. We're in this messed up feedback loop, and if these trends continue, we're gonna lose a key tool in our fight against climate change. [music out]
Jacob Margolis 19:22
[forest ambi] Back with Nate, talking about the Giant Sequoias, our forests, the future of everything, was heavy. And I asked him, "How do you even begin to process where things are headed?"
Nate Stephenson 19:37
This landscape, that I thought was timeless, that would always be there, always looking the way it looks now, is changing and is changing rapidly. That's, that's really hard to accept. You know, we all live in this crazy amped up world where things are happening really fast all the time, and it can wear you out. And then you visit a national park, and at least for me and I think for a lot of people, you calm way down, and you realize there's something much bigger than you out there, something more enduring, more permanent. [forest ambi out]
Jacob Margolis 20:15
When I was in my teens, I was lucky enough to go on a backpacking trip here. And at the time, I had a lot going on, you know, having issues with friends, uh, hard time in school, just trying to figure out the kind of person I was- my brain, just a tangle of anxious thoughts. I was really unhappy. [music in] But when I was carrying that heavy backpack, sleeping outside, surrounded by trees and marmots, and just eating so much canned tuna that it now makes me nauseous when I smell it, my mind quieted. And for the first time, in a long time, I felt okay. But being back in Giant Forest, seeing the way it's changed, I just want to so badly know if it'll still be around for me, you know, for my kids, or really for everybody. [pause] Maybe you've felt some of this existential ache too, when landscapes that you grew up with, the ones that brought you joy and peace, are taken away by climate change. There's actually a word for it: solastalgia. It's a combination of the word solace and nostalgia. Sometimes we talk about climate change in terms of projections, like how hot the planet will get, and what we could lose in the future. Solastalgia is the way we feel now about what's already happening. And it's easy to live in this place of darkness in your mind, and I kinda expected to have my dark feelings reinforced by my visit to see, you know, burnt out Giant Sequoias. What I learned is that there's still hope to be found. That it's still possible for us to intervene and save our forests from at least some of the catastrophic fire. [music out] Which brings me back to Christy's fight to save General Sherman. After the break, a wild plan, a window of opportunity... and space blankets. [break]
Jacob Margolis 20:15
[wind through trees ambi] When we left General Sherman, it was defenseless in the face of oncoming fire, and Christy had been told that conditions were too dangerous for a rescue operation. She was gutted.
Christy Brigham 22:39
But then two days later, after that, I got a call at [laughing] 5:30 in the morning. Um, it was hilarious because I don't sleep with my cell phone, my cell phone's downstairs. So they called my husband, who does sleep with his cell phone, and he's like, I hear him go like, Hello? And it was the superintendent, and he's like we've got a window! Where's your militia? [laughs] We're gonna go rake!
Jacob Margolis 22:59
[music in] The pictures are wild- the air filled with smoke, a crew of about 30 people literally raking several feet of pine needles away from the trees. And then... they brought out the giant aluminum blankets.
KPIX CBS SF Bay Area News Announcer 23:16
Firefighters have used an innovative approach to minimize damage to the trees. They've wrapped their base in a fire and heat resistant material and cleared much of the brush from the area. It's a last line of defense, if they're not able to slow the fire down.
Jacob Margolis 23:30
The idea is to prevent embers from burrowing beneath the tree's bark and killing it from the inside out. And so the crew rushed to wrap the base of General Sherman like a chipotle burrito in giant space blankets, hoping to insulate it from the worst to come. [music out]
Christy Brigham 23:43
[forest and wind ambi] Don't you think he looks good? Majestic? A survivor? [JM laughs softly]
Jacob Margolis 24:01
General Sherman made it. There it was- enormous, awesome- in the original sense of the word. Christy let us climb over the fence so we could get close.
Christy Brigham 24:13
I like to hug them. [JM: Can we hug it?] Of course.
Jacob Margolis 24:15
Can we hug? Uh, okay. I gotta hug the tree. [CB laughs]
Sophia Paliza-Carre 24:18
...it's gonna happen. Lifelong dream achieved. [CB: Heck yeah.]
Jacob Margolis 24:22
This is really the only reason I did the podcast [CB laughs] 'cause so we could work our way here to hug the tree.
Jacob Margolis 24:28
Arms wrapped around Sherman, for a bit, the solastalgia went away. And we were just there, being all cheesy, just enjoying the wonders of nature while we still have them.
Christy Brigham 24:40
I love these trees. I mean, they're, they're amazing. They've lived for over a thousand years, and they lived through previous fires and droughts and being around them is really powerful, and it's such a testament to endurance and nature's ability to withstand. And so the loss emotionally of those trees is upsetting and it's also upsetting because it didn't have to be this way.
Jacob Margolis 25:10
The water, the foil, and the fire retardant were worst-case scenario defenses. But there's another part to this story. Even though destructive, high severity fire burned through other parts of the park, killing lots of Giant Sequoias, when it got to Giant Forest, something amazing happened.
Christy Brigham 25:29
Once the wildfire got into the heart of Giant Forest, it really laid down and actually went out.
Jacob Margolis 25:35
Giant Forest did not get destroyed by high severity fire, in part because Giant Forest is different from lots of forests across the Western U.S. [music in] Many of the forests getting decimated by high severity fire have had fuels building up in them for over 150 years. And I can't emphasize this point enough- fuel buildup is a huge deal. And the reason for all this fuel to build up? Instead of letting good low to moderate fire naturally clear out debris, and small trees, for over a century, we've prioritized putting out fires in our forests. I know this sounds counterintuitive but putting out those fires has resulted in worse wildfires. [pause] In Giant Forest though, the National Park Service has been setting their own good fires for decades. [music fades out] So when a bad fire shows up, doesn't have all this extra fuel to burn.
Christy Brigham 25:57
This burn program is amazing. The people h- who've been working here at Sequoia and Kings Canyon for three decades- the work that they have done is amazing and it's saved Giant Forest. But have we done enough of it? Absolutely not. The answer is to actively manage, to do the prescribed burning, to do the restorative thinning. The answer is to manage these forests so that they are fire resilient as they're meant to be. [music in]
Jacob Margolis 27:10
You've probably heard about this before. It's called prescribed burning. Before Europeans showed up, Native American tribes intentionally burned the land for all sorts of reasons- to clear space for food to grow, to hunt game, and yes, to reduce the risk of destructive wildfires. We see that prescribed burning slows down and even helps stop big fires, that forests that have had these treatments are more resilient to heat and water stress in the face of climate change. For me, that's reason to hope. Here's what's wild about all this- this problem of fuel buildup had once been solved in California by the tribes who lived here. And then, about 150 years ago, it all went catastrophically wrong.
When you're running for your life, when you are constantly worried that somebody is going to show up and, and shoot you, that prevents you from being able to do things like cultural burning.
Jacob Margolis 28:17
That's next time on The Big Burn.
Jacob Margolis 28:19
[theme music in] The Big Burn is created, written, reported and hosted by me, Jacob Margolis. Shana Naomi Krochmal is our Vice President of Podcasts. Antonia Cereijido and Leo G are the executive producers for LAist Studios. Our producer is Minju Park. Additional production by Natalie Chudnovsky. Our intern is Bruno Lopez-Vega. Anjuli Sastry Krbecheck is the senior producer. Editing by Sophia Paliza-Carre and Meg Cramer. Fact checking by Caitlin Antonios. Sound design and mixing by E. Scott Kelly. Original music by Andy Clausen. Our website, LAist.com, is designed by Andy Cheatwood and the digital and marketing teams at LAist Studios. The marketing team of LAist Studios created our branding. Artwork for this show by Dan Carino. Thanks to the team at LAist Studios, including Taylor Coffman, Sabir Brara, Kristen Hayford, Kristen Muller, Andy Orozco, Michael Cosentino, and Leo G. Support for this podcast is made possible by Gordon and Dona Crawford, who believe that quality journalism makes Los Angeles a better place to live, the Strelow Family, and by the Corporation for Public Broadcasting, a private corporation funded by the American people. The Big Burn is a production of LAist Studios. Subscribe wherever you get your podcasts. [music out]