From the helicopter, Charlie Castro could gaze down into the heart of the tree, a hollowed-out cavity alive with raging red flame.
Just hours earlier, he had been in Montana, where forest fires were racing across the timberland. But when lightning struck one of the giant sequoias in California’s celebrated Grant Grove, sparking a blaze that threatened to spread across its thousand-year-old trees, the National Park Service needed a firefighter who could climb right up to the conifer’s burning crown, succeeding where efforts by land and air had failed.
It was a job that Castro, an Indigenous tree-climber, was uniquely suited for. It would also be one of the greatest challenges of his career.
Part of the last generation born and raised in Yosemite national park, Castro – a member of the Mono Paiute and Miwuk tribes – has witnessed first-hand how fire has reshaped the American west, intensifying into the massive blazes seen today.
He has also been on the front lines of change, watching as public understanding of wildfires has shifted – and with it, park policy.
But on that day in August 1967, Castro alone would face the flames. As he circled high above in the helicopter, Grant Grove stretched out below him, the jewel of Kings Canyon national park.
Some of the largest trees in the world towered under his feet: giant sequoias stout enough for cars to pass through their trunks. One of them, the General Grant Tree, was considered the second-biggest tree in the world, with a trunk volume of 46,608 cubic feet – nearly 50% larger than the cabin of a Boeing 747 airplane.
And in their midst burned a matchstick. Known as the California Tree, the flaming sequoia was spitting hot embers into the air, dangerously close to the General Grant.
Armed with pencil and paper, Castro started to map his plan of attack. Because tomorrow would decide whether the trees could be saved.
Tomorrow, he would start his perilous climb.
Yosemite’s last ‘Indian village’
Even now, at 89 years old, Castro is no stranger to fire. Just two years ago, lightning sparked another blaze that threatened the small town where he lives, advancing up the slopes to Kings Canyon and Sequoia national parks, two adjacent preserves in the Sierra Nevada mountains.
“That was tremendous,” Castro recalled from his robin-egg-blue house in the hills of Three Rivers, California, four hours east of San Francisco. Smoke clouded the air, as firefighters swaddled giant sequoias nearby in shiny, flame-resistant foil.
It was a necessary precaution. Where the flames burned most intensely, no vegetation survived – including thousands of mature sequoias.
Since 1950, California has seen the size of its fires increase dramatically. One blaze alone scorched 1,032,648 acres in 2020, setting a state record.
Experts believe these massive, high-severity wildfires have already decimated up to 20% percent of the adult giant sequoias in the last eight years, endangering an already fragile population that only exists in the Sierra Nevada.
Part of the issue is the climate crisis. With warmer springs come faster snowmelts, lengthening the fire season. And with hotter temperatures, plants can quickly dry into kindling, ripe for a spark.
But another factor is the human relationship with fire – when to extinguish it, when to foster it and how policies of total fire suppression have allowed larger blazes to erupt instead.
Over his 42 years with the park service, from 1952 to 1995, Castro was trained to battle the flames and tend to the trees, as part of the wood crew at the two parks.
It’s a history that has left his hands “in bad shape”, so knotted and arthritic that he can no longer squeeze a climbing rope. But at the height of his career, he was an expert high-climber, one of the few individuals the park service trusted to scale its mightiest trees.
Castro, a short, sturdily built man with a puckish smile, credits his Indigenous ancestors for his athletic streak. Walking into his living room, he gestures to a wall dotted with black-and-white photographs.
That’s his mu’a, he explains, using the Mono term for “grandmother”. And there’s his togo, or grandfather, pictured sitting at the base of a tree, a walking stick clutched between his fingers.
“He was a great, great, great runner,” Castro said. “He used to run mail from Yosemite valley over the Sierra Mountains, run the mail clear over to [the town of] Lee Vining, spend the night and run back the next day.”
His togo was part of a disappearing tradition, though. Ever since settlers entered Yosemite Valley in 1851, waves of militias, miners and merchants had sought to push the Indigenous inhabitants from their lands.
Yosemite’s conversion into parkland in 1890 only expedited the process. Some of the park’s greatest proponents, including the environmentalist John Muir, felt the Indigenous presence clashed with the untouched paradise they perceived among Yosemite’s peaks and meadows.
Muir went so far as to say the Mono people “seemed to have no right place in the landscape”, calling them “mostly ugly” even as he waxed poetic about the “ineffable beauty” of their home terrain.
But Indigenous people nevertheless remained in Yosemite, even forming a part of the nascent tourism industry’s workforce. Up until the 19th century, they were also known to use fire to clear the ground of excess brush – a practice that had the added benefit of removing fuel for larger blazes.
Still, they continued to face pressure to move outside the park. And after the second-to-last Indigenous village was razed to make way for a hospital, all that remained by the 1930s was a cluster of 15 cabins shaded beneath the valley walls.
That was Castro’s childhood home: Wahhoga, Yosemite’s last “Indian village”.
“Our cabins were all close to each other in a great big gigantic circle,” he recalled. In the center sat a building with communal showers, toilets and garbage cans – a favorite destination for the local bears.
Castro remembers it as a tight-knit community, the kind where neighbors would gather to play music together or share meals. For those get-togethers, the local women would grind acorns into patties, and the hunters would contribute deer meat for mulligan stew, simmered over an open fire.
The memory of those meals still makes Castro cry out with excitement – “God dang!” – as his face creases into a smile.
Castro and his friends had a way of dispatching any bears attracted by the leftovers.
“The bears were always there at the Indian village. Always,” Castro said. He and the other children would chase them away by throwing rocks. “We used to really pepper them. We were good with slingshots.”
But when the bears sought refuge in the village trees, that’s when the big guns would come out.
“We had some of those long poles we stole from the Yosemite Park Curry Company,” Castro said with a grin. “We’d get them hot, and we’d poke the bears in the butt.”
The bears could exact revenge, though – even from high up in the canopy. “I mean, bears have got a big bladder and a big belly,” Castro said. “Sometimes they let loose, and you had to make sure that you weren’t underneath.”
It was at Wahhoga that Castro began to develop his climbing skills. As a child, he used to shimmy up the oak trees near the village to build tree houses and swings.
And with recreational climbers flocking to the area to scramble up Yosemite’s granite walls, Castro picked up tips from passersby. They even let him borrow their pitons and carabiners: the spikes and metal rings used to scale the rock face.
“They liked me, those guys,” Castro recalled. “Sometimes I was walking to school and they’d say, ‘Good morning, Charlie!’”
Castro got his first job with the park service through a classmate. The friend’s father, Emil Ernst, was a park service forester, and he hired Castro to help trim back Yosemite’s overgrown gooseberry bushes.
But Castro quickly realized the work wasn’t for him. The heat was so stifling, he felt he could barely breathe. And he feared rattlesnakes lay hidden in the brush.
“Emil, I know you gave me a job,” Castro remembers telling Ernst. “But I’m going to have to quit. I don’t want to be cutting any more gooseberry.”
Ernst shot him a look. “Oh no, you aren’t. You’re not quitting. You come to me Monday morning. I’m going to give you another job.” His new assignment? Climbing and cutting trees with the wood crew. It was the start of a multi-decade career.
‘Every move counted’
Years passed. By 1970, the United States was in the twilight years of its war in Vietnam. The old draft system had been replaced with a lottery, and Steve Sorensen, a college student, was afraid he would be selected to serve.
“The government wanted to send me to Vietnam and kill me, you know?” he recalled thinking.
But Sorensen had concocted a plan: if he could get into the backcountry – the remote wilderness where few dared to go – he could be “completely free”.
Sharp in math, he passed the civil service exam and landed a job as a seasonal laborer at Sequoia and Kings Canyon national parks.
On his first day, he drove to the parks’ headquarters at Ash Mountain. There, a short, dark-haired man in his 30s stood waiting for him: Castro. He had moved to the parks in 1964, leading efforts to remove hazardous trees and limbs.
His work had earned him some renown: Castro said he was deployed across the western United States, from Arizona to Hawaii, to work on park service projects.
“You’re going to have to cut your hair,” Sorensen remembers Castro saying the moment they clapped eyes on each other. At the time, Sorensen’s shaggy locks tumbled past his ears.
But the young recruit was undeterred. If a haircut was the cost of working in the forest, Sorensen thought, so be it.
For the next 14 years, Sorensen worked on and off under Castro’s supervision. “It was paradise for me. I loved it from the first day,” he said. “We had a whole crew of guys like me who were sort of refugees, trying to not get drafted in the military.”
But cutting trees was tough, and Castro was no easy boss. There was a hierarchy to follow.
Newcomers like Sorensen started out as laborers, carrying supplies and hauling fallen branches. The next level up was axman. Only when you could prove you were responsible with a hatchet could you graduate to a chainsaw.
And then came the most dangerous tier: scaling the parks’ massive trees to bring down branches and trunks.
That job required strength, and Sorensen remembers Castro tested recruits by challenging them to one-armed pull-ups.
“Charlie was a superb athlete and just a master of tree climbing. Just graceful. Every move counted. He never made one move that wasn’t important or didn’t need to be done,” Sorensen said.
It was a time of transition at the park service – and Castro and Sorensen were on the front lines. Some of the change was cultural. Sorensen said he and some of the younger workers clashed with park bureaucracy, led by older second world war veterans with military-style efficiency.
Other prominent shifts, however, had to do with fire policy.
The creation of the national parks in the late 1800s coincided with growing fears about wildfire. Some of the deadliest blazes in US history took place at that time: one brush fire in 1871 killed an estimated 1,200 people, a death toll that has yet to be surpassed.
By 1905, the US Forest Service had been created with a mission of near total fire suppression. Fire had to be extinguished with utmost haste.
Early forest service leaders such as Henry Graves explicitly condemned “the custom of Indians and early settlers” to stage controlled burns, which involved purposefully lighting fires to clear away excess vegetation.
This custom resulted in “fearful devastation”, Graves claimed in 1912. “The doctrine of light burning,” he concluded, was “nothing less than the advocacy of forest destruction.”
That perspective endured for much of the 20th century. But by the late 1960s and early 1970s, park leadership had started to question the wisdom of framing fire as the enemy. The foresters at Sequoia and Kings Canyon were at the forefront of the change.
Having observed natural fires burn themselves out in Yosemite, George Briggs, the parks’ chief of resource management, instituted a system of “let burn” zones, where fire could be used to thin the underbrush.
At the same time, other scientists were discovering the crucial role fire played in the life cycles of plants and animals.
Jim Harvey was just a child at the time, but his father, the ecology professor H Thomas Harvey, studied how fire affected the parks’ giant sequoias, some of the oldest and largest trees in the world.
“I still remember one of the great things that ever happened in my life was that my dad gave me a drip torch and said, ‘Jim, walk around this perimeter and start a forest fire,’” recalled Harvey, now a marine ecologist.
Because he was the oldest of his parents’ three children, Harvey had the special privilege of accompanying his father during his research. That’s how he met Castro. Stocky but cat-like, Castro inspired wonder in the young Harvey, who watched him rig a makeshift elevator that rose into the canopy of a 290ft sequoia.
“He was almost mystical to me, because of his ability to do what he did, which was climb trees – big trees,” Harvey recalled.
Harvey himself got a chance to ride once in the elevator, which was little more than a tiny metal cart stabilized with rope and cable. As he rose higher and higher, his father shrank against the forest floor, a pinprick next to the monstrous girth of the tree.
“I’d seen hundreds and hundreds of sequoias by that time in my life,” Harvey explained. But his view from the elevator left him in awe: the limbs he was approaching in the canopy were as thick as trees themselves. “I was going up there, going, ‘Wow.’”
But by that time, in the 20th century, there were fewer and fewer young sequoias sprouting – and scientists like Harvey’s father were starting to realize it was because of fire suppression.
Sequoias had evolved to live with a moderate amount of fire. The policy of extinguishing all fires had cut the trees off from an important part of their life cycle.
The elder Harvey and his colleagues estimated the tree outfitted with the elevator had produced 20,697 new pinecones in 1970 alone. But without fire, many of the tiny walnut-sized cones remained sealed, unable to crack open and release their seeds.
And even if the pine cones did burst open, their seeds had little chance of sprouting. The forest floor was blanketed in leaves and other debris, and smaller trees blocked the sun – impediments that might otherwise have been cleared by natural fires or controlled burns.
“We have restrained fires in a lot of ways because we thought they were destructive and bad,” Jim Harvey explained. “But the reality is the environment before humans were here dealt with fires all the time.”
His father, he remembered, would spend evenings around the campfire with park rangers, imploring them not to tell the public that fire was inherently bad.
Not everyone was easily swayed. And to some, the notion of encouraging burns – or intervening in the park landscape in other ways – was unconscionable.
“People today still don’t get it. They still don’t understand why. Prescribed burning is the only thing that’s going to save California from the disastrous wildfires that we’ve had,” Sorensen said.
Experts warn, however, that prescribed burns are not a cure-all for decades of fire suppression.
“There are a lot of misconceptions about wildfire, and it used to be that all fire was bad,” said the research ecologist Alexandra Syphard of the Conservation Biology Institute. “Now there’s this prevailing message of burn it, manage it, cut it, thin it. And it is inappropriately applied too broadly.”
She warns that fire policy must be tailored to specific ecosystems, to take into account the unique needs of different species – like the giant sequoias Castro specialized in scaling.
‘A towering inferno’
As a climber, Castro lived by a grim maxim: “You make a mistake, it might be your last.”
Every new climb came with risks. Castro knew it. He made sure his crew knew it, too. Just because you’d had one successful ascent didn’t mean the next one would go smoothly.
Castro himself had never fallen. But not everyone he knew was so lucky. On his first big climb, Sorensen found himself in the canopy of Grant Grove as bolts of lightning began to rain down.
“I was scared. I was actually shaking,” Sorensen recalled. A seasoned outdoorsman, Sorensen had experience as a rock climber. Ordinarily, he knew his way around a set of ropes. But this time, his mind had gone blank: “I couldn’t remember how to tie the knot to come down.”
He threaded the rope and unthreaded it, again and again, afraid to trust his weight to it. All the while, the thunderstorm seared the sky with blinding flashes of light.
That’s when Castro’s voice travelled up to him: “Sorensen, you’d better get your ass down out of that tree before the lightning brings you down.”
The words jolted Sorensen back to reality. He knew Castro was trying to encourage him – to get him to focus on the job at hand. And it worked.
“I just tested the knot and in a second was back on the ground,” he recalled. “Charlie knew what was happening.”
But decades later, in April 1990, the worst would happen. Another Indigenous climber, Truman James, plummeted 150ft from a sugar pine in Kings Canyon, where he was trimming dwarf mistletoe.
“I watched him come all the way down. He came down and he was all broken inside,” Castro says quietly.
In the small windowless space of his home office, he points to a photo of a man on his wall, wearing blue jeans and an Oakland Raiders baseball cap. His fist pounds the desk. “He died on the way to the hospital. I’ll never forget that day.”
Across nearly nine decades of life, Castro has experienced his share of loss. Darla, his beloved wife, passed away in 2017. He lost one of his adult children to cancer. Even Wahhoga, his childhood home, has been wiped away, razed by the park service in the 1960s.
Castro wrote letters to protest the demolition. They went unanswered.
“That’s the end of the Indian village, I said, but it’s not the end of the Indians,” Castro remembers writing. Efforts are now under way to restore the village as a site for education and spiritual ceremonies. An oak-and-cedar-beam roundhouse has already started to take shape.
The forests of his past have themselves experienced devastation. The park service estimates that flames consumed more than 85% of the giant sequoia’s territory in the Sierra Nevada between 2015 and 2021, as the climate crisis super-charges the fire season.
Experts fear the intensity of these modern fires is greater than what the sequoias have evolved to withstand. One blaze alone, 2020’s Castle fire, is thought to have killed up to 10,600 giant sequoias with trunks 4ft thick or more – amounting to at least 10% of the total population.
But amid the loss, a story of hope has endured in the Sierra Nevada: of an uncontrollable fire that was doused thanks to the intervention of one man.
On that August morning in 1967, and Castro stood at the base of the burning sequoia, preparing to hoist himself up to the flames.
Helicopters had been deployed to extinguish the fire in the California Tree – but to no avail. Local media reported that even after 13 separate drops, amounting to tons of water, the flames continued to roar in the tree’s canopy and core.
Around 9am, it was time to start the climb. Castro knew better than to begin from a sequoia’s base, though. Their trunks were too broad, their bark too spongy, and their lower sections were generally bare of any branches.
So Castro turned to a nearby fir tree instead. Equipped with little more than some drinking water, a radio and his climbing equipment, Castro started to ball some rope into what he calls a “monkey fist”: a knot with enough weight to sling over the fir tree’s branches.
That allowed him to lift himself into the fir tree, gaining a height of about 170ft – just tall enough for Castro to send another rope into the lofty branches of the sequoia.
He then swung across the chasm between the two trees, arriving at the sequoia’s burning canopy. Even through the bark, Castro could feel the heat from the flames emanating.
“I almost got to the top of that tree, that big California Tree,” Castro recalled.
But as he stopped to take a drink of water, something gave him pause. There was a hum coming from inside the tree. “I said: this damn tree’s vibrating. This tree’s actually vibrating, it was burning so hot in the bottom. It was a towering inferno, and it was just quivering.”
Worried that his ropes might pick up a spark or the wood would crumble beneath his weight, Castro dropped 15ft back down the trunk . His mind started to race: “I wonder how much bark there is in there, between me and the hollow spot where it’s burning.”
But he quickly corralled his thoughts. “I just kept my mind on it. Kept my mind busy about what I had to do with that big tree before that top might collapse.”
With cables and rope, he pulled fire hoses directly into the tree’s canopy, directing the nozzles where others couldn’t reach.
When firefighters on the ground turned the water on full blast, Castro could feel the ropes tighten under the strain. He warned the onlookers below to step back. As water surged into the flame-filled cavity, one of the knots on the trunk looked ready to burst.
“I hollered at them, ‘Get out!’” Castro recalls. A jet of water and flame and debris suddenly exploded from the trunk. “It pushed that great knot out of the trunk of the tree, blew it on down to the ground.”
Castro was soaking wet by the time he set foot on solid land around 9.30 that night, more than 12 hours later. But the flames had been defeated. The chief ranger on site handed Castro a beer.
Castro quickly downed it and proceeded to drink another. Right then and there, he took a vow: “I’m not going to ever climb this tree again.”
The tree miraculously survived. So did the grove. And the name Castro would become inextricably linked with their legacy – and the story of fire in the American west.