The first reports of smoke came to the Yosemite Emergency Communications Center at 2:04 pm on July 7, 2022. Only eight days had passed since the National Park Service (NPS) had declared “fire season” in Yosemite. Although every fire in Yosemite brings anxiety, this one would be of special concern on account of its location: the southwest boundary of the Mariposa Grove of Giant Sequoias. Even the US President had been briefed about the fire’s threat to the Grove according to a Tweet by White House assistant press secretary Abdullah Hasan.
The Grove, one of the largest stands of Giant Sequoias in the world, contains over 500 mature redwood trees. It stirs awe and wonder within all those contem- plating their height, girth, and ancient origins. Even though redwood trees benefit from fire for seed dispersion and germination and possess a measure of protec- tion from fire as a result of the tannic acid within their fibrous bark, high-severity fires can be fatal to individual trees.
For example, the Castle Fire alone (2020) in Sequoia National Forest killed between 7,500 to 10,600 Giant Sequoias according to the NPS. The combined loss from the KNP Complex and Windy Fires (2021) near and in Sequoia National Park/Forest “is estimated to be 2,261 to 3,637 large sequoias that have already been killed or will die in the next three to five years” according to that same NPS report. So, despite its benefits, fire can pose a serious threat to these majestic conifers.
The fire that started in Yosemite on July 7th, called the Washburn Fire, would pose a similar threat to the Mariposa Grove. Its origin occurred near the Washburn Trail, hence the name. This trail, a short 1.8-mile (2.9 km) hike to the Grove, starts at the east end of the parking lot at the Mariposa Grove of Giant Sequoias Welcome Plaza. The Washburn Trail can be used instead of the shuttle service for those who wish to walk to the Grove or when the shuttle buses are not in service (e.g., in the winter months). Despite not possessing grand views like other notable trails in Yosemite, it serves a vital purpose in maintaining access to the Mariposa Grove.
From the trail the fire spread northward toward the Grove. The LA Times reported that “two battalion chiefs were teaching a chainsaw class” to a large group of firefighters nearby in Wawona, allowing for a quick response to the fire. Consequently, by the time the fire had reached half an acre, two engine trucks and a helicopter had been dispatched to the area. The Grove had to be evacuated, and according to the LA Times article, “park rangers enlisted civilian tour bus drivers to evacuate more than 450 visitors from the Grove.” The complete evacuation from the Grove ‘wrapped up’ within 90 minutes allowing firefighters to focus on protecting the Giant Sequoias.
As fires often do, this one spread quickly under hot and dry conditions, consuming 250 acres by the next day. By July 10, the fire had burnt 1,591 acres with 0% containment and had reached into the south and west boundaries of the Grove..
In the Castle Fire, protective foil-like sheathing had been wrapped around endangered redwoods and structures. However, the Mariposa Grove and the area around the Grove had received prescribed burns over the years, reducing the threat from ground fuels that could cause a more severe canopy fire. So, tactical measures for the trees, the Grizzly Giant in particular, included installing sprinklers at its base to increase the humidity and moisture content of the decaying ground vegetation. This lowered the risk of high-severity burns that destroyed so many redwoods in the Sequoia fires.
Although the Mariposa Grove giants received no foil-like ‘wrap’ at their base, one historic structure located amidst the upper grove of Sequoias did require ‘wrapping.’ The log cabin, built in 1930 and known officially as the Mariposa Grove Museum, replaced a similar styled cabin made by the famed “Guardian of Yosemite” Galen Clark in the 1860s. Clark's cabin (see photo below) acted as an informational center for visitors and promoted the preservation of the Sequoia trees. Many still refer to the 1930 structure as the Galen Clark Cabin.
Placed on the National Register of Historic Places in December 1978, the 1930 cabin was boarded up during the Grove’s three-year renovation project from 2015 to 2018.
Although still boarded up (see photo below), the peaceful cabin remains an important reminder of the historic first encounters of visitors to Yosemite and their contribution to the preservation of the Grove of Giant Sequoias. Consequently, the cabin received special attention during the fire.
As a protective measure, the NPS and Yosemite Fire opted to utilize the fire-resistant “blanket” to safeguard the wooden structure from fire damage. The foil-like covering, known as “Aluminized Structure Wrap”, provides a protective shield for structures in high-severity wildfires. When the same wrap was used in the Castle Fire to shield the Kern Canyon Ranger Station in Sequoia National Forest, the building remained unscathed.
After completing the wrap of Kern Canyon Ranger Station, one unnamed firefighter noted (on a Facebook post) that the wrapped “structure stood tall in the center of the clearing, sparkling and reflecting the sunlight. A truly incredible sight. It had been entirely wrapped and secured in structure-wrap (similar looking to aluminum foil) . . . I couldn’t help but to feel like I was wrapping Christmas presents for my family,” he wrote.
Surely those firefighters assigned to “wrap” the Mariposa Grove Museum felt similarly when they completed their assignment. No doubt they, and the many visitors who have sat on the veranda of that cabin, sensed much relief knowing it would be protected against any fire that made it to the upper Grove. They could even confidently say to themselves “that’s a wrap” when seeing the cabin completely covered and reflecting the sun.
As for “wrapping up” the Washburn fire, 100% containment occurred on August 3, 2022. The fire completely extinguished itself when a late summer rain fell on September 19, 2022. A total of 4,886 acres burned to the west, north, and northeast of the Grove. According to Wildfire Today, approximately 340 acres burned within the Mariposa Grove itself.
Although full containment on any fire is met with celebration, it was still too early to say completely “that’s a wrap” on the Washburn Fire. Like smoldering embers and lingering smoke, one issue remained: How did the fire get started?
Please read Part 2 coming soon as I address that question.
Photo below: Burnt areas of Mariposa Grove of Giant Sequoias
near a western portion of the Grizzly Giant Loop Trail (One year after Washburn Fire).
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