A NASA-funded study has found that the giant sequoias, the world’s tallest tree species, were nearly four times more likely to survive extreme wildfires in forests that were managed with controlled burns.
A recent study examined how sequoia populations were affected by ‘historically unprecedented’ wildfires in 2020-2021, where a record 6.8 million acres burned in California.
Giant sequoias are only naturally found on the western slopes of the Sierra Nevada mountain range and can reach more than 300 feet in height and more than 30 feet in diameter.
They are keystones of the ecosystem and serve as carbon sinks, water filters, and structural habitats for birds, insects, and small mammals.
Using a variety of modelling techniques to understand the fires and trees
Examining data on 26,403 giant sequoias across 19 groves in Sequoia and Kings Canyon National Parks over the two year period of intense wildfires, the team found that 19% of the total mature giant seqouia population across the area was destroyed.
Recent wildfires have caused far more deaths among giant sequoias than usual, threatening their future.
The team combined lidar, stem maps, high-resolution imagery, and modelling techniques to estimate giant sequoia mortality in relation to forest management practices and found that prescribed burns saved roughly 1,800 giant sequoias.
Prescribed, or “controlled” burns help the trees by thinning underbrush, dead wood, and other dry fuels, reducing the likelihood of mortality from high-intensity wildfires.
