Burned Area Rehabilitation projects help save sequoias

Planning for the future. Giant sequoia cones collected from the handful of surviving trees in Board Camp Grove.

NPS / A BISHOP

During 2020 and 2021, two major wildfires burned through twenty-eight different sequoia groves within Sequoia and Kings Canyon National Parks (SEKI). Giant sequoias are one of the most fire-adapted species on earth. Within the wildfires’ footprints, these full suppression wildfires likely provided some ecological benefits to mixed conifer forests and giant sequoia groves that burned at low and moderate severity. However, Burned Area Emergency Response (BAER) planning, as well as follow-up analysis by the park, USFS and United States Geological Survey (USGS) staff, documented some troubling impacts where the wildfires burned at high intensity. According to satellite imagery and field surveys, when combined with losses suffered on adjoining lands from these wildfires, as well as a third wildfire, the 2021 Windy Fire that burned sequoia groves on US Forest Service lands, killed an estimate of up to 14,000 sequoias, or 19%, of all large sequoias on earth.

Board Camp Grove April 2020. Notice the lack of living overstory trees and the large amount of bare soil.

NPS / C BRIGHAM

These losses were unprecedented and revealed a need for new approaches to studying and mitigating for wildfire impacts. The BAER plan allowed the team to identify areas that would be difficult for sequoias to regenerate in due to loss of overstory sequoias and a high potential for erosion that could remove any surviving sequoia seeds. Follow-up field surveys, funded by the NPS Inventory Program, showed large areas of two surveyed groves with little to no sequoia regeneration. Surveys are planned for four more impacted groves.

Burned Area Rehabilitation (BAR) funding, in response to the 2020 Castle Fire and 2021 KNP Complex Fire, allowed park managers to begin planning for sequoia reforestation and funds to begin the work once the planning process is complete. During fiscal year 2022, this funding allowed park staff to work with partners to collect cones from two of the six sequoia groves that burned at high severity, fund cultural resource surveys of these areas to inform reforestation planning, and work with cooperators to begin planning and analysis for all six of the damaged groves.

The window for natural regeneration post-wildfire for giant sequoias is very short; the trees capitalize on the soil conditions and small canopy openings immediately post-wildfire. It’s vital to have seed stock and seedlings to begin planting immediately after planning and analyses are complete. The funding from the BAR program is allowing the parks to do this pre-work while completing the environmental analysis needed to determine what conditions are on the ground and what restoration actions might be needed. A combination of funding from NPS BAR and NPS Inventory Program was used, coordination across multiple divisions within the parks, NPS programs, and other agencies like the USGS and USFS, makes this process possible.

This work is ground-breaking in its effort to address ecological damage to forests caused by a combination of more than a century of wildfire suppression and exclusion and hotter droughts in the Southern Sierra Nevada driven from climate change. As these BAR projects continue into fiscal year 2023, the staff at the parks hope that their efforts will allow giant sequoia groves to recover from these impacts of wildfire and continue to thrill generations of visitors to come.