This is why firefighters wrap Sequoia trees in aluminum blankets
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A blanket was recently given to the world's largest tree to protect it from a wildfire. A photo of General Sherman, a sequoia with a base measuring 36 feet in diameter caused a lot of interest about how blankets might be used against flames.
According to the park, the KNP Complex Fire now has burned 23,743 acres. It is now 0% contained. Each day, the fire has increased by thousands of acres.
General Sherman towers over Sequoia National Park's north end of Giant Forest. As the KNP Complex Fire nears the area, firefighters and park officials were on high alert.
To save General Sherman and other high priority trees, firefighters wrapped the sequoias with aluminum-based blankets. They also sheathed the tree's thick bark with synthetic material to ensure they survived.
There are some signs that this strategy worked. The Four Guardsmen, sequoias at the edge the forest, were saved by the team over the weekend.
To protect homes, blankets were used in the past
Jon Wallace, firefighter and chief of operations for the KNP Complex Fire said that the sequoias were "wrapped in house-wrapping material. It's a kind of an aluminum foil fabric that goes around their base."
The blankets are used by firefighters "to prevent embers getting into the tree through the old fire scars," Christy M. Brigham (chief of resources management and science, Sequoia & King Canyon National Parks) told ABC station KGO-TV.
Catfaces or fire scars are a threat because they could open the door to new fires to attack giant trees. Wallace provided an update Monday morning on the efforts to put out fire scars on trees as crews deal with spot fires. To help cover the scars on high-priority trees blankets were used.
Zoomen this image toggle caption Jae C. Hong/AP Jae C. Hong/AP
Brigham stated that fire blankets were used for many years to protect structures.
Brigham explained to CNN that the firefighters were instructed to treat the special sequoias as if they were buildings, wrap them up and then rake and remove the heavy logs.
It's not just about aluminum
Although the shiny fire blankets are attracting a lot of attention, they are not the only tool firefighters use to protect the ancient sequoias.
Also, work crews moved organic matter that was decaying and duff from the forest floor away form the trees.
Wallace stated that they don't want the duff to catch on fire and smolder long-term at the base of these trees, adding that it could "start boiling the roots."
He said, "That's really the thing that's going to hurt them."
Wallace said that extraordinary measures are being taken to preserve the trees due to the extreme dry conditions in the forest.
Firefighting crews also have been digging firelines and performing protective burns in areas around trees, lodges, and other structures within the park. The area has also seen aircraft fly above it, dropping to limit or extinguish flames.
Wallace stated that sprinklers were used almost non-stop to protect the museum, Wallace added.
Access is also crucial. Firefighters were able to use walking trails to battle the blaze in the Giant Forest. Timber cutters were dispatched to clear roads and ensure firefighters have access to the area, as large trees fell on highways.
Controlled burns have been helping sequoias for decades.
Wallace stated, "The good thing is that the Park Service has done quite a bit of prescribed burning there since the 1960s," as he described firefighters' job of protecting the Giant Forest.
He said, "So it's making them job a lot simpler."
Wallace said that when flames ran through the brush, up a slope towards the forest, Wallace also added that their height fell from frightening heights to a more manageable 2 or 3.
Sequoias live for thousands of year, and some of the 68 groves on the Sierra Nevada's west flank have survived for more than 3200 years. Officials are worried about recent wildfires' intensity and frequency. These trees have survived fires before.
Early estimates suggest that the Castle Fire of 2020 caused the death of up to 14% large sequoias within the Sierra Nevada region. This included up to 10,600 trees. This accounts for approximately a third the area of their groves within the Sierra Nevada.
Through a project called Giant Sequoia Lands Coalition, experts are working to determine which sequoia trees are due for controlled burns and most at risk to wildfires. It includes representatives from all levels of government, including the University of California and Tule River Indian Tribe.
Sequoias, also known as "pioneer" trees, rely on fire for reproduction.
According to the California Department of Parks and Recreation, giant sequoia trees need the unpredictable heat of fire for reproduction.
The department states that sequoia seeds must first be freed from their cones before they can reach heights greater than 300 feet. This is done by lighting fires which dry the cones and crack them open. Other ways flames can help are also possible.
According to the department, fire loosens soil and allows seeds to fall into mineral-rich earth. This also gives them the opportunity to absorb moisture previously absorbed by larger plants. Fires are also a way for sequoia seeds to grow by clearing away duff and other growth from the forest floor.
From the late 1800s to the late 1900s, fire was rare in the sequoia forest after the arrival European settlers. According to the National Park Service, this caused "a huge failure of giant sequoia reproduction."
According to the National Park Service, Giant sequoias "are pioneer species. They are among the first plants to take root after a disturbance happens."
