Portions of a report from the Sequoia & Kings Canyon National Parks:
Although some giant sequoia trees have stood for thousands of years and are adapted to withstand frequent low and mixed severity fires, preliminary estimates suggest that the 2020 Castle Fire killed between 31 to 42% of large sequoias within the Castle Fire footprint, or 10 to 14% of all large sequoias across the tree’s natural range in the Sierra Nevada. This translates to an estimated loss of 7,500 to 10,600 large sequoias. These estimates may change as we acquire new data.
Why Did This Happen?
A combination of one hundred years of fire suppression along with climate change driven hotter droughts has resulted in a denser forest with unprecedented levels of fuel loading. These conditions have changed how wildfire burns in the southern Sierra Nevada, resulting in large areas of high severity fire effects and mass fire events that generate their own weather. The Castle Fire of 2020 was one of these megafires.
What Steps Can Be Taken to Protect the Sequoia Groves?
In order to reduce fuels and restore wildfire resilience, we will need all available tools in the toolbox. Prescribed burning remains one of the most important management tools to reduce fuels in sequoia groves, favor regeneration, and increase resilience of these groves to climate change and wildfires. However, smaller burn windows and massive fuel accumulation means that prescribed fire is not able to keep up with the treatment needed and some areas cannot be safely treated with fire. Restorative thinning is an additional too that can be used to help protect the sequoia groves.