Wildfire concerns near Yosemite grow as controlled burns nixed

But then there’s the narrow strip of forestland near the southwestern edge of Yosemite National Park, a mere 5 miles from the prized giant sequoias of the Mariposa Grove.  

Goss calls the troubling area a gap because it runs between the boundaries of two recent wildfires — the 2017 Railroad Fire and the 2018 Ferguson Fire. The already burned areas are unlikely to ignite again for at least several years, but the strip in between those fires out near Fish Camp and Oakhurst hasn’t burned in recorded history, and that’s a big problem.

The U.S. Forest Service identified it years ago as a priority for prescribed burns, which are widely regarded as the most important tool for preventing catastrophic fire. The gap is one of several areas within the Sierra National Forest where officials hope to reduce the threat of catastrophic wildfire in the wildland-urban interface, in and around foothill and mountain communities. 

And although they've had some success in getting fire down on the gap’s understory in previous years, the job isn’t done, Goss says. Prescribed burns scheduled for the gap this year had to be put on hold.

“We did have plans to do those this year, but it got too dry,” Goss says. “They’ll be back on the books this fall if we get an opportunity.”

That’s a big if. With the changing climate, the window of opportunity for prescribed burns is shifting and shrinking in California, experts say. Across the state, controlled burns that used to mostly take place in the fall and sometimes the spring have been postponed due to the elongating of the fire season.

“We’re losing the shoulder seasons,” UCLA climate scientist Daniel Swain tells SFGATE. “The time you used to be able to do prescribed burning has really been constrained.”

This year, a new opportunity to do wintertime burns arose thanks to the unusual dryness, Swain says, but fire managers had to contend with rain and snowstorms. And while springtime burns are also an option, they’re not ideal for ecological reasons. “There are new bunnies running around and birds hatching,” Swain says. “You don’t always want to burn the forest then.”

Yosemite National Park has had some of its prescribed burns put on hold this winter and spring, resulting in what Dan Buckley, the park’s chief of fire and aviation, refers to as “chinks in the armor.”

But “we’re pretty well armored,” he tells SFGATE, adding that Yosemite has had an effective prescribed burning program since the early 1970s and that “just about the whole park has had recent fire history within the last 40 to 50 years.”

That’s why, Buckley says, when more than 4 million acres of California burned last year — including the Creek Fire’s near-380,000 acres just to the south of the park — only 9,600 acres inside Yosemite burned. Although lightning set off those fires within the park, they became “resource objective fires,” according to Buckley, meaning that the park allowed the small wildfires to burn within fire-adapted areas to consume understory fuels, much as a prescribed burn would.

Still, there are some areas of concern.

Up near the park’s border with Stanislaus National Forest, fire danger has already been set at high, and that’s come as a shock to some local tour business owners and residents of nearby communities.  

“We are already in the middle of the first red flag warning, and the fire danger in Stanislaus National Forest is set at high,” Elisabeth Barton, co-founder of Echo Adventure Cooperative, says. “In the 12 years I have been running recreation in Yosemite, fire concerns have never crossed my mind in May.”

A prescribed winter burn in Yosemite targeted 2,000 acres near that forest, Buckley says, but it had to be postponed after just 35 acres were completed. “We got snowed out,” he says. “Then we shut down this spring because of the Pacific fisher status.” The small mammal is endangered in the southern Sierra Nevada, which is home to a population of an estimated 100 to 500 individuals.

Over in the Crane Flat area, park officials targeted 1,126 acres north of Big Oak Flat Road, where dead trees and other forest detritus have fallen into “jackstraw piles” resembling oversized games of pick-up sticks. Although a few dozen acres were burned, the project had to be postponed in early April due to an unfavorable weather forecast.

Meanwhile, the crews have turned their attention to Yosemite Valley, where a 439-acre prescribed burn is scheduled for this week. The project focuses on seven parcels east of the El Capitan Crossover, according to Yosemite’s website, with ignition likely to last three days and smoke hanging around the valley — and drifting down canyon in the evenings — for about two weeks.

“We haven’t been able to do as much prescribed burning as we would have liked to,” Buckley says. “We’ve been in and out of [the window for] prescription quite rapidly. It’ll be too dry and too windy. Then we’ll have a storm come and it’ll be too wet and too soggy.” To find the “sweet spot,” he says, “we have to look for opportunities year-round. We have to be ready.”

Apart from prescribed burns, the rapidly approaching fire season has meant firefighting crews in the national forests surrounding Yosemite are already up and running. The crews for Sierra National Forest are providing “initial attack resources” on “new starts,” Goss explains, while continuing to clear roads of debris from the 100 mph Mono wind event that wreaked devastation in January.

“This is the earliest we’ve ever mobilized these crews,” Goss says.

Sierra National Forest actually saw two small fires last week, he added: a campfire that escaped in West Kaiser Campground and a “zombie fire” in the Creek Fire burn area, where a dead tree that had been smoldering for months rekindled. Both fires were quickly contained.

In Yosemite, the fire teams are “training and preparing for the fire season,” according to the park’s public information officer Scott Gediman. “Our new firefighters are coming on board over the next few weeks,” Gediman wrote in an email.

Vacancies in permanent and seasonal firefighting positions are now being filled, Buckley adds, and additional federal dollars have helped build the team from 42 employees last year to an estimated 54 this year. “There’s more of an emphasis from the federal government to establish a more permanent workforce,” he says, which will help bolster the now year-round efforts to fight fire and execute prescribed burns.

Six of those 54 people are an all-female crew provided through a partnership with the California Conservation Corps, which aims to increase diversity and inclusion. They’ll be trained and used as a field crew from June to mid-August, Buckley says.

Based on key indicators like fuel moisture content, experts are estimating that Yosemite and surrounding forestland will hit peak fire season about a month and a half or even two months earlier than usual. At that point, it would only take a lightning strike near Oakhurst or a spark caused by friction on a dragging car near Fish Camp to ignite the unburned gap mere miles from the Mariposa Grove.

One of the park’s prime attractions, the grove includes more than 500 mature giant sequoias that stretch to more than 285 feet high and date back more than 2,000 years. Last year during the Creek Fire, the largest single-source fire in California history, crews mobilized quickly to prepare the grove for fire. They worked long hours in smoke to clear the area of fuels and placed a protective wrap around the Mariposa Grove Museum.

The flames never reached the grove. But this year, Steve Wilensky, the founder of a forestry nonprofit called CHIPS, which provided crews to the grove, wonders if that luck will hold. His crews are now working with many others around Oakhurst to clear out the large amount of biomass and toppled trees left in the wake of the Mono wind event.

Although there are numerous people on the ground and more money than ever has come in for fire season preparation, Wilensky says, he's worried the unprecedented effort won't be enough. 

“Nature is way ahead of us," he says. "If we keep changing the climate, we’re never going to catch up, no matter what we do. But for now, we still have a beautiful Sierra to protect, and we should get on with that."