On June 16, 2022, fire personnel were completing multiple ignitions in the heart of the Giant Forest of the Sequoia and Kings Canyon National Parks as the Moderate Resolution Imaging Spectroradiometer (MODIS) on board NASA’s Aqua satellite acquired a true-color image of the region. The red “hot spot” marks the areas of actively burning fire in the Tharps-Hazelwood Prescribed Burn. Heavy smoke rises from the fire and blows to the northeast.
The Giant Forest is precious territory, filled will hundreds of monarch sequoia trees including the world’s largest tree (measured by volume), the General Sherman Tree. This tree stands 275 feet (83 m) tall and over 36 feet (11 m) in diameter at the base. These massive, ancient trees were threatened by the severe KNP Fire Complex, which burned 88,307 acres between September 9 and December 16, 2021. The huge, incredibly hot fire killed burned in much of the Sequoia and Kings Canyon National Parks, killing more than a thousand sequoia trees and damaging structures. Thanks to good fire management, including prescribed burns, aggressive fire-fighting techniques, and an element of sheer luck, the Giant Forest was spared serious damage.
Prescribed fires are fires that are deliberately set to manage forest and reduce the danger of potentially catastrophic wildfire. Giant sequoias are a species that have adapted to fire. Their bark is protective and can survive low-grade fires while the seeds germinate in the ash bed left behind a fire. Fire opens the forest canopy, allowing sunlight to reach seedlings. Fires also reduce deadwood, which stops reproduction of sequoia and increase the risk of a devastatingly large wildfire. The National Park Service notes that historically, widespread fires have burned in sequoia groves at average intervals ranging from 6 to 35 years.
Prescribed fires contribute to forest health and public safety. The National Park Service explains that a fire's "prescription" includes detailed analyses of geographic and ecological conditions. A prescription is the window within which a fire may be ignited. These conditions maximize our ability to control the fire and to minimize smoke in local communities. If the weather doesn't meet the prescription, the fire is not ignited.
The Tharps-Hazelwood Prescribed Burn had been originally planned for last spring but was postponed due to site conditions being too dry at the time. InciWeb Incident Information System quotes Superintendent Clay Jordan as saying, “I am relieved we were able to complete this critical prescribed burn. Last year’s KNP Complex Fire demonstrated how important low-intensity recent fire history is in protecting giant sequoia groves from catastrophic wildfire.”
The first ignition of the Tharps-Hazelwood Prescribed Burn occurred on June 9 and the last fire was started on June 16. With ignitions complete, firefighters will continue to patrol the area as vegetation inside the unit burns down. Many trails and areas near the prescribed burn will be closed until further notice, although visitors can still visit many features, including the General Sherman Tree.