Trees that are several thousand years old in California's Sequoia National Park are in danger of being destroyed in this month's wildfires. Things are currently so bad that the base of some of the world's largest trees are being wrapped in aluminum fire-resistant blankets.
The trees being wrapped are giant sequoias, and the largest tree of all is called General Sherman. This tree is about 2200 to 2700 years old, 275 feet tall, over 36 feet in diameter at the base, and with a circumference of 102.6 at the base. (Almost as tall as the Statue of Liberty!).
Giant sequoia trees are adapted to fire, but both drought conditions and fires are getting more intense (climate change!) and can overwhelm them. Last year's Castle Fire destroyed an estimated 7500 to 10,600 mature giant sequoia trees that ranged in age from hundreds to 3000 years old. This is about 10 to 14% of these trees on Earth!
As flames crept closer to California’s cherished sequoia trees firefighters took an unusual step to protect them, wrapping the giant bases in fire-resistant blankets.
The shiny material that helps quell flames, commonly used to protect structures, is rarely applied to natural features, but crews fighting the KNP Complex fire in the Sequoia national park said they are doing everything possible to protect the iconic trees.
The KNP Complex fire – which consists of two lightning-sparked blazes burning together – forced the evacuation of the park this week, and parts of the town of Three Rivers outside the main entrance remained evacuated Thursday. The wildfires are among the latest in a long summer of blazes that have scorched nearly 9,195 sq km in California, destroying hundreds of homes.
By Friday morning, the KNP Complex fire had grown to more than 11,300 acres, and was within a mile of the famed Giant Forest. The General Sherman tree was among the sequoias that were wrapped, along with the Giant Forest museum and other buildings, Paterson said.
The General Sherman tree is the largest in the world by volume, at 1,487 cubic meters, according to the National Park Service. It towers 84 meters high and has a circumference of 31 meters at ground level.
The wrapping was applied only to the base of the tall trees that stretch hundreds of meters into the sky. “It is just being applied by firefighters on the ground so it is not possible to put it 100 feet up or anything,” Paterson said. “The idea is to keep ground fire from getting at the tree where it is most likely to burn, which is close to the ground.”
The Colony fire, one of two burning in Sequoia national park, had grown toward the Giant Forest, a grove of 2,000 sequoias, but firefighters have so far been able to keep the blaze out of the grove. Paterson said conditions on the ground are aiding in the firefight and that officials are hopeful the trees will stay safe.
Giant sequoias are adapted to fire, which can help them thrive by releasing seeds from their cones and creating clearings that allow young sequoias to grow. But the extraordinary intensity of fires – fueled by climate change – can overwhelm the trees. That happened last year when the Castle fire killed 7,500 to 10,600 large sequoias, according to the National Park Service.
A historic drought and heat waves tied to climate change have made wildfires harder to fight in the American west. Scientists say climate change has made the region much warmer and drier in the past 30 years and will continue to make weather more extreme and wildfires more frequent and destructive.