California Sequoias   Photo: Brian Schaller, Wikimedia CC

By Amy Lupica, ODP Contributing Writer

Hundreds of giant sequoia trees were killed in the Castle Fire in California, according to experts. The intensity of recent wildfires has done more damage than the trees can handle, despite sequoias, the world’s most massive trees, being naturally resistant to fire. The fires threaten the lives of thousands more sequoias, some of which are over 3,000 years old. The destruction of giant sequoias in wildfires has become increasingly common since 2015.

Why This Matters: The fiery death of these trees is a canary in a coal mine. Sequoias are not only resistant to fire but usually thrive in it. Their cones, no larger than chicken eggs, burst to release seeds when subjected to large bursts of heat. Their thick bark protects them from heat damage and their elevated branches and leaves usually avoid destruction. The fact that these trees are now facing such destruction is a sign that wildfires are intensifying at an alarming rate due to the increasingly dry climate in the northern part of California. Worse yet, giant sequoia forests serve as massive carbon sinks. According to the U.S. Department of Agriculture, sequoias hold more carbon per tree than any other species on earth. Many carbon sinks are declining worldwide, and losing giant sequoias could cause the release of more carbon into the atmosphere.

History Written in Wood

Sequoia trees can tell experts a lot about previous fires dating back hundreds of years. Charred markings and scars in their rings show fires that moved through the Sierra in years past, some started by lightning or by Indigenous groups in the region. Before the arrival of settlers and federal anti-wildfire policies, these moderate, and even beneficial, fires moved through the forest every 10 to 30 years. Higher intensity fires that occurred allowed new generations of sequoias to take root.

The strongest fire that can be observed by these natural historical records came in 1297. The year took place during what experts call the Medieval Warm Period, a period of higher temperatures in some parts of the globe. The 2020 Castle fire was even worse. Nate Stephenson, a research ecologist with the U.S. Geological Survey, believes that two factors influenced the destruction of the Castle fire: climate change and a lack of controlled burns. “If fire hadn’t been excluded from those groves for so long, the fire effects probably would have been a lot less severe. Just that buildup of fuel,” he said.

Park rangers cite a lack of funding and resources for lacking forest management. Eric La Price, the Sequoia National Forest’s Western Divide District ranger, explained, “We barely have a budget to keep the lights on.” It cost the government more than $100 million to fight the Castle fire. “Imagine if we had $107 million to do reforestation, thinning, and prescribed fire,” said La Price.

Experts and environmentalists agree that the forests are at a crossroads. Kristen Shive, science director for the Save the Redwoods League says a choice must be made, “More and more fire is going to happen on the landscape. We need to decide what kind of fire we want. Do we want fire that is healthy and restorative in our ecosystems, or what we had this year?”