Photograph by Gary Kazanjian, AP
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Sequoia trees in Grant Grove are charred in Kings Canyon National Park, California, on September 12, 2015.

Photograph by Gary Kazanjian, AP

Sequoias and Historic Stump in Path of California Wildfire

But the massive trees are well-adapted to survive flames, say experts.

While 20,000 people are evacuated in the wake of several massive wildfires burning across Northern and central California, firefighters are scrambling to protect some of the state’s natural treasures.

The largest active fire in the state, the Rough Fire, has burned 138,053 acres in and around Sequoia and King’s Canyon National Parks in the Sierra Nevada. More than 3,200 personnel are battling the blaze, which is at 40-percent containment, according to the U.S. Forest Service.

Media reports have focused on how the blaze may threaten giant sequoias and a famous trunk called the Chicago Stump, which was shown at the Chicago World’s Fair more than a century ago. The stump is all that remains of the huge General Noble sequoia, which was cut up in 1897 for transport to the fair.

But as of Monday the Chicago Stump “is in really good shape,” says John Nichols, a Forest Service information officer assigned to the Rough Fire. “It’s wrapped in fire-resistant material and has three sprinklers on it.”

The blaze is on a slow creep in the vicinity of the stump, which is now anchored into the ground and would be too difficult to move, Nichols says.

Living sequoias, some of which are several thousand years old, also are weathering the blaze well.

“They are a fire-dependent species that are well adapted to survive burns,” says Nichols. “In fact, fire helps them get the next generation of sequoias started.” That’s because fire encourages the trees to drop their cones en masse. The blaze knocks out competition from other plants and provides a great shot of fertilizer in the form of ash. (Learn more about sequoias and fire.)

Watch: Learn more about wildfires and sequoias.

Tough Trees

Sequoias have fibrous, fire-resistant bark that can grow up to two-feet thick, insulating them from damage, says Stephen C. Sillett, a Humboldt State University ecologist who has received grants from the National Geographic Society to study the giants in Sequoia National Park. The trees’ massive size and canopy also help cut down on undergrowth around them, which reduces fuel for fires.

"The big trees are going to be fine," says Sillett.

Giant sequoias are the world's largest single trees by volume. They reach an average height of 160 to 279 feet (50 to 85 meters) and average diameter of 20 to 26 feet (6 to 8 meters). Record trees have been identified at 311 feet (94.8 meters) and 56 feet (17 meters) in diameter. The oldest known giant sequoia is estimated at 3,500 years old. (See "Giant Sequoias Grow Faster With Age.") The huge trees live in about 70 groves that are spread along the western slopes of the Sierra Nevada.

Watch: Fighting wildfires.

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