California's Castle Fire Killed up to 10,000 Redwood Trees, at Least 10% of World's Supply

A California wildfire that ravaged the southern Sierra Nevada last year resulted in the loss of a tenth of the world's mature giant sequoias, according to a draft report obtained by the Visalia Times-Delta.

The report used satellite imagery and modeling from previous fires, finding that between 10% and 14% of the world's mature giant sequoia population was wiped out, according to the Times-Delta.

"I cannot overemphasize how mind-blowing this is for all of us. These trees have lived for thousands of years. They've survived dozens of wildfires already," Christy Brigham, chief of resources management and science at Sequoia and Kings Canyon National Parks, told the Associated Press.

Forest managers remarked that the loss of the trees would have a significant impact on the environment for years to come. Redwoods are some of the most efficient natural oxygen scrubbers, removing and storing carbon dioxide in the atmosphere. They also serve as essential habitat for wildlife and protect the watershed for farms and communities on the San Joaquin Valley floor.

For more reporting from the Associated Press, see below.

Castle Fire
A structure lies in ruins from a wildfire in the Sequoia National Forest in the southern Sierra Nevada Mountains west of Ridgecrest, CA, August 3, 2000. The fire last year resulted in the loss of a tenth of the world's mature giant sequoias. David McNew/Newsmakers

Brigham, the study's lead author, cautioned that the numbers are preliminary and the research paper has yet to be peer-reviewed. Beginning next week, teams of scientists will hike to the groves that experienced the most fire damage for the first time since the ashes settled.

"I have a vain hope that once we get out on the ground the situation won't be as bad, but that's hope — that's not science," she said.

The newspaper said the extent of the damage to one of the world's most treasured trees is noteworthy because the sequoias themselves are incredibly well adapted to fire. The old-growth trees — some of which are more than 2,000 years old and 250 feet (76 meters) tall — require fire to burst their pine cones and reproduce.

"One-hundred years of fire suppression, combined with climate change-driven hotter droughts, have changed how fires burn in the southern Sierra and that change has been very bad for sequoia," Brigham said.

Sequoia and Kings Canyon have conducted controlled burns since the 1960s, about a thousand acres a year on average. Brigham estimates that the park will need to burn around 30 times that number to get the forest back to a healthy state.

The Castle Fire erupted on Aug. 19 in the Golden Trout Wilderness amid a flurry of lightning strikes. The Shotgun Fire, a much smaller blaze burning nearby, was discovered shortly afterward, and the two were renamed the Sequoia Complex.

Sierra Nevada
FILE - In this April 22, 2021, file photo, provided by the National Park Service, shows a smoldering tree in Sequoia National Park, Calif. The giant sequoia was found smoldering and smoking in an area of the park burned by the 2020 Castle Fire. At least a tenth of the world's mature giant sequoias were destroyed by a single California wildfire that tore through the southern Sierra Nevada last year, according to a draft report prepared by scientists with the National Park Service. Tony Caprio/National Park Service via AP, File