Firefighters extinguish hot spots from the Washburn fire in Yosemite National Park, California, on July 11.
Nic Coury / AFP via Getty Images
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Nic Coury / AFP via Getty Images
Firefighters extinguish hot spots from the Washburn fire in Yosemite National Park, California, on July 11.
Nic Coury / AFP via Getty Images
BERKELEY, California – The iconic grove of ancient and giant Sequoia trees in California’s Yosemite National Park is no longer directly threatened by the wildfires still burning across the southern portion of the park. and the nearby Sierra National Forest.
The Washburn Fire is more than 50% under control, and officials said Sunday that residents of the mountain community of Wawona can begin returning to their homes.
But it takes more than the hard work of firefighters in the wilderness, luck or a change of wind to protect the majestic trees of Mariposa Grove, many of which are 2,000 years old, of which There is a Grizzly Giant well over 3,000 years old.
Instead, foresters and ecologists say that a half-century of intentional burning or ”regulatory fires” in and around the area has significantly reduced ” fuel. ” the forest is there, allowing the fire to pass through the forest without the trees being harmed.
“The fire has penetrated the forest and fortunately we have a 50-year history of prescribed fires,” said Garrett Dickman, a forest ecologist with Yosemite National Park. The park began to regularly see intentional fires in the area in the early 1970s. “So it could have been a very different outcome if we hadn’t prepared for this fire for decades. century,” he said.
Indeed, the Sequoia controversies have grown old in recent years was not so lucky.
Native American tribes He has been cultivating for a long time and continues to win Practice intentional fires to reduce fuel consumption. This ”good fire” along with other mechanical measures and forest thinning are important tools Fire ecologists say to help avoid catastrophic wildfires. That’s because these purported fires reduce ”the amount of” combustible fuel that has accumulated in a centuries-old policy that prioritizes extinguishing almost any wildfire.
Climate change threatens giant trees
Caused by man Climate change is only getting worse Experts say the danger posed by these accumulated fuels is that they are making droughts worse, temperatures higher and contributing to increasingly unstable weather.
The Washburn Fire was fueled by dry, accumulating forest fuel. But as the fire swept into Mariposa Grove, the largest and best-known of the park’s three clusters of aging sequoia trees, it plunged into the area of the most recent fire, slowing progress and raging. .
Once it hits that area, “the intensity of the fire is greatly reduced, the rate of spread is reduced, and firefighters can quickly get involved and begin immediately laying down hoses and hoses and threading.” direct the fires around the forest,” says ecologist Dickman.
The fire brigade also set up a large sprinkler system, removing smaller trees that could help the fire spread and clearing debris to protect the forest.
But the “good flame” is probably the biggest factor. Dickman uses a donut analogy. Mariposa Grove and the immediate surrounding area is the donut pit, where they have focused their prescribed fire program for decades. But the outside area of the donut, he said, hasn’t burned in more than 100 to 130 years.
The Washburn Fire burns near the south entrance of Yosemite National Park on July 11 near Oakhurst, Calif.
Eric Paul Zamora / The Fresno Bee / Tribune News Service via Getty Images
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Eric Paul Zamora / The Fresno Bee / Tribune News Service via Getty Images
The Washburn Fire burns near the south entrance of Yosemite National Park on July 11 near Oakhurst, Calif.
Eric Paul Zamora / The Fresno Bee / Tribune News Service via Getty Images
So it’s impressive to go beyond the grove, into the squishy part of the “donut”, if you will, the fuel is much larger and the burning behavior is more intense, spreading and volatile.
“The length of the flame that we see inside [Washburn] The fire was tens of meters high, if not hundreds of meters, he said. a plane almost got hit by a bullet fire fighting.
“That’s a lot of heat to get the branches into the air. The firefighters couldn’t really get in when, you know, there’s 125 tons of fuel burning,” Dickman said. “This way, this way, it’s too hot.”
Old sequoias are one of the most fire-resistant and fire-adapted plants on Earth. They are built to withstand fire and need it to regenerate. But today’s fires are usually larger, burn hotter, and move faster due to global warming and the fuel loads from that wildfire extinguishing history.
“The fires they evolved to withstand were very, very different from the fires of today,” says Dickman.
Sequoias need fire, just not so much
The thick bark and trees towering over the forest floor both help protect them from wildfires. And they rely on low-intensity wildfires to reproduce as the heat opens their cones and scatters their seeds to the forest floor below to restart their life cycle.
But the reality of “high-severity fires” now is putting California’s wildfires under increasing threat. Since 2015, a series of devastating wildfires, including deadly campfire, has devastated the state, destroyed houses, businesses, life and many old trees. In the last two years alone, fires have killed nearly 20% of all adult giants.
Experts say the successful defense of Mariposa Grove is an outstanding example and potential case study of the power of consistent purposeful fire.
In contrast, thousands of large Sequoias were killed in the 2020 Castle Fire in Sequoia National Forest and in fires in other parts of the state, including Fire KNP Complex and Windy Flame. Some of those areas have a history of fires that are regulated to reduce the amount of forest fuel. But the difference is that in those areas it’s not done as often or as widely and consistently as it is in the Mariposa Grove area, Dickman said.
“The groves [in the Castle fire] worms in the wild. No very good access. It’s very difficult to get firepower on the ground … from a straightforward logistical point of view,” he said.
If there’s one silver lining from this fire, says Dickman, it’s federal, state and NGO organizations. work harder now more than ever sharing information, lessons learned, and research tools and techniques on intentional burning and how to help reduce the risk of catastrophic wildfires and preserve these spectacular trees.
“We’re all working together to try to do what we can to take more of the action that we know we need to do to protect these giant sequoias in the future.”
Another federal agency for land, the Forest Service, has stopped all regulated fires across the United States for a 90-day safety review after New Mexico’s intentional fire is out of control and caused the largest wildfires in that state’s recorded history. Critics have called it a nationwide pause a politically directed overreaction also highlights how the agency’s wildfire policies are out of sync with the reality of the climate change fires that ravage the West every year. Ecologists are calling on the Forest Service to accelerate the speed, scale and support of their targeted firefighting program.
