Written by: Bhavyaa Chauhan

Wildfires have been a hot topic in the mainstream media in the past decade. Forests, specifically those in California, have been prone to intense wildfires, creating threats to biodiversity and the climate. The giant Californian native, is no stranger to fires. In its 2,200 years of life, it has been exposed to over 100 prescribed burns. Prescribed burns are controlled fires that are planned out by scientists to help trees build resistance and, for sequoias, better reproduction. Even though this year’s fires making their way across the Sierra Nevada serve serious threats, The General Sherman and its grove is protected with prescribed fires since the 1960s. Luckily, The General Sherman, the largest tree in the world, has been protected with “a fireproof blanket”.

Figure 1

Wildland firefighters creating a controlled fire line in a mixed conifer forest

NPS/Anthony Caprio

The KNP Complex: A Possible Threat to Sequoias

The KNP (Kings Canyon National Park) complex fire is one of four active fires currently burning in the southern Sierra Nevada which is a mountain range on the west coast that contains the majority of the world’s Sequoias. These fires were caused by a lightning storm, and so far, they have burned over 28,421 acres of land. 

The closest flames to the Giant Forest were only a mile away. However, the Giant Forest is well prepared to withstand any fires that come its way. The main problem that creates a threat to the forest  is the  damage that can happen to the foliage of the trees. Sequoias have thick bark that can buffer high intensity fires, however, the intensity of the KNP complex and the warming climate could mean hotter and taller fires that the trees are not prepared to withstand. Taller fires could mean that the Sequoias’ foliage, hundreds of feet above the ground, could burn and cause severe damage to the tree’s main hydraulic system, causing the tree to die. Fortunately, scientists have quickly recognized this imminent threat and raked away any debris close to the border of the grove. The debris could catch on fire and create an even more intense fire. The fire has so far only had minor contact with 4 of the Sequoias from the Giant grove. 

Figure 2

The red dots indicate hotspot perimeters of wildfires.

Source: San Francisco Chronicle: California Fire Map & Tracker

Should we be Worried? 

At first glance, it seems that the Sequoia groves are well protected and do not need much attention. But, the real threat lies for groves other than the Giant Forest which are not well prepared to handle fires and are in remote areas that are difficult to access. These trees are surrounded by smaller trees that have had no controlled fires or treatments over the years. Since the smaller trees block the sequoia groves, scientists have a difficult time reaching the sequoias to conduct controlled fires. If the smaller unprescribed trees catch on fire, there is a better chance that the flames could spread to the Sequoias faster.

History of Fire and Prescribed Burning.

Fires behave differently now than they did a few hundred years ago. Due to the warming of the climate and human caused fires, wildfires have become much more aggressive. Before the West was colonized, Native Americans used fire to manage and shape landscapes. In fact, “prescribed burning” originated from Indigenous tribes. The regular fires kept the forest healthy and allowed Sequoias to produce seeds faster. Prescribed burning was done by tribes like the Yurok, Karuk and Hoopa Tribes of Northern California in order to have richer harvests and support life cycles of the trees. When you have a prescribed fire, it helps make the trunks of trees more resistant to fire and assists in delivering more nutrients to the canopy of the trees. 

However, the white settlers from the East completely misunderstood the practice, and by the 1900s, there were laws put in place that ordered all and any fires to be terminated. Additionally, logging practices created more debris making the forest more prone to wildfires. Charcoal remnants in tree rings tell scientists about the progression of fire frequency. These suppression rules primed forests for intense wildfires that could’ve been prevented if they allowed prescribed burns. These laws eventually changed and allied wildlife scientists to conduct prescribed fires and help save many of our world’s largest trees including the Sequoia.

Figure 3

A tree set ablaze.

Source: Noah Berger/Los Angeles Times

Drying out of the West

California has been one of the largest victims to historic drought and extremely dry climates. Climate change is only speeding up the process between droughts in California. Furthermore, wildfires and human activity combined are creating a disproportionate amount of greenhouse gases, which are the driving force behind climate change.

             If rapid intense wildfires continue through the West coast, it could mean the extinction of several plant and animal species—including the Sequoia. As of now, scientists have done everything possible to protect and care for General Sherman, but as wildfires are increasing, it can become harder to protect these giant trees. 

References and Sources

Borunda, A. (2021, September 22). Wildfires threaten the world’s oldest trees-but prescribed

burns are protecting them. Retrieved October 22, 2021, from

https://www.nationalgeographic.com/environment/article/wildfires-threaten-the-worlds-o

dest-trees-but-prescribed-burns-are-protecting-them

InciWeb developed and maintained by USDA Forest Service, F. (2021, October 21). KNP

complex. Retrieved October 22, 2021, from https://inciweb.nwcg.gov/incident/7838/

Marlon, J. R., Bartlein, P. J., Gavin, D. G., Long, C. J., Anderson, R. S., Briles, C. E., . . . Walsh,

1. K. (2012). Long-term perspective on wildfires in the Western USA. Proceedings of

The National Academy of Sciences, 109(9). doi:10.1073/pnas.1112839109

Press, T. (2021). Sequoia National Park’s Giant Forest unscathed by wildfire. Retrieved October

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https://abcnews.go.com/Technology/wireStory/sequoia-national-parks-giant-forest-unsca

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Team, C. (2021, October 21). California fire map: Tracking wildfires burning across the State.

Retrieved October 22, 2021, from https://www.sfchronicle.com/projects/california-fire-map/