A conservation group has closed a $15.65 million deal to buy the largest privately owned giant sequoia grove left on Earth, an ancient forest with hundreds of the endangered trees that can live for 3,000 years and rise nearly as tall as the Statue of Liberty. Due to its size, health and age diversity — with sequoias ranging from seedlings to Methuselahs — this grove represents "the most consequential giant sequoia conservation project of our lifetime," according to the group's president.

Known as Alder Creek, the grove covers a seemingly modest 530 acres (2 square kilometers), but that's a big deal for giant sequoias. The iconic trees once lived throughout the Northern Hemisphere, but they now exist in only 73 isolated groves, all located on the western slopes of California's Sierra Nevada mountains. This particular grove of Sequoiadendron giganteum packs a lot into its 530 acres, including 483 sequoias with trunks at least 6 feet (1.8 meters) in diameter, along with a few hundred smaller sequoias of varying ages.

That age range is a big reason why this grove is so valuable, according to Sam Hodder, president and CEO of Save the Redwoods League (SRL), a century-old California nonprofit that's been working to acquire Alder Creek for more than 20 years.

"Many giant sequoia groves are just a single age class, usually in the thousands," Hodder told MNN when the deal was announced in September 2019. "In this one, a real indication of its health and resilience is that there are giant sequoia of all age ranges." While any remaining giant sequoia grove is a rarity, he adds, "it's rarer still to have multiple age classes, and such a healthy forest ecosystem."

SRL signed a purchase agreement with the Rouch family, which has owned the grove since the 1940s. That was a big step after two decades, but the sale wasn't official — until now. There was the small matter of $15.65 million, which SRL had to raise by Dec. 31 before it could take ownership. The group did that with a public fundraising drive on its website that rallied for help right up to the deadline. Donations rolled in from more than 8,500 donors from all 50 states and around the world.

'A thoughtful process'

The Stagg Tree, located in Alder Creek, is the fifth-largest tree in the world. Max Forster/Save the Redwoods League

Alder Creek is an island of private property surrounded by Giant Sequoia National Monument, which spans about 328,000 acres (1,327 square km) and connects to the even larger Sequoia National Forest. The Rouch family has long used the grove for commercial logging, Hodder says, and even cut down giant sequoias in the early days, although since the 1960s they've reportedly only logged non-sequoia species like sugar pine and white fir. SRL plans to eventually transfer ownership to the U.S. Forest Service, so the sequoias can join the federally protected wilderness around them.

That won't happen for a while, though, since SRL expects to hold the property for five to 10 years. That's partly because this kind of public-acquisition process moves slowly, Hodder says, but also because SRL wants time to study the grove and implement a plan for good stewardship, making sure the trees are healthy and ready before handing them over to the public.

As part of that preparation, the group plans to open Alder Creek for public access even before giving it to the Forest Service, hoping to help the ecosystem ease into an unfamiliar role as a host for human visitors. "This property has been in private ownership, and it has never had public access," Hodder says. "We want to go through a thoughtful process to plan out public access, so when it does get conveyed into the national monument, it's ready for its public purpose."

Trial by fire

'Our focus will be on protecting the magnificent forest that already exists at Alder Creek,' Hodder says, along with planning for public access. Max Forster/Save the Redwoods League

Although people logged some giant sequoia groves in the late 1800s and early 1900s, the species' modern decline is largely due to misguided efforts last century to suppress natural forest fires. Giant sequoias are adapted to regular, low-burning fires, which help their seedlings by generating nutrient-rich soil, thinning the canopy to let more sunlight reach the forest floor, and creating open areas with less competition from faster-growing plants. Scientists have since realized the folly of suppressing natural wildfires, but despite phasing out that practice, the legacy of fire suppression still haunts the giant sequoia.

"Because we've been suppressing forest fires that used to occur on a regular basis in this landscape, all the species that would be kind of culled by a natural, low-burning fire have been allowed to grow to maturity in an unnatural way," Hodder says. "So one of the challenges in stewardship of giant sequoia is finding a way to address that unnatural buildup of combustible fuels."

The logging of other species at Alder Creek might have inadvertently helped the giant sequoia, Hodder adds, replicating the effect natural fires would've had if they weren't suppressed. "They eliminated some of the sequoia's competition, and as a result the sequoia themselves are remarkably healthy, and the property has lower fuel loads than the landscape around it."

That could be a significant advantage for the Alder Creek sequoias, since even this fire-adapted species seems to be increasingly at risk from wildfires. As climate change raises temperatures and worsens droughts in California, including the decline of Sierra Nevada snowpack, the lingering effects of past fire suppression have left many forests primed to erupt.

While the purchase ensures Alder Creek won't be sold to a developer, it will be much harder to protect these or any sequoias from the effects of climate change. Still, on top of reducing other risks and generally nurturing the forest's health, Hodder hopes the grove can serve as a kind of living laboratory, helping us learn whatever we can to help these ancient trees survive.

"This gives us the opportunity to understand what's going on with these new threats and exposures, and to do the forest management that needs to be done," he says. "Science-driven forest stewardship to reduce the fuel load in a way that restores the natural balance for the giant sequoia. To help prepare these groves for the hotter, drier fires that are coming."