An upward view of giant sequoias in Sequoia National Park, California.
CNN  — 

A San Francisco conservation group has kicked off a public fundraising campaign to buy and protect the world’s largest remaining privately owned giant sequoia forest. It just needs $15 million.

Save the Redwoods League announced Tuesday that it has reached an agreement to purchase the 530-acre property, known as Alder Creek, from the current owners if it raises the funds.

The forest is home to some massive trees, including the world’s fifth largest, known as the Stagg Tree.

And here’s a fun fact: Giant sequoias are the third longest-lived tree species on the planet, the National Park Service says. (The oldest known tree was 3,266 years old.)

The property is about 200 miles from Los Angeles and is surrounded by the Giant Sequoia National Monument, the league said.

It was these kinds of massive trees that inspired the national conservation movement more than 150 years ago, beginning with the protection of Mariposa Grove in Yosemite National Park, President and CEO of Save the Redwoods League Sam Hodder said.

“Today, Save the Redwoods League has the opportunity to continue this conservation legacy by permanently protecting Alder Creek and its hundreds of giant sequoia trees,” Hodder said.

‘The need is urgent’

Hodder calls Alder Creek Grove a “crown jewel of giant sequoia forests,” in a post on the organization’s website.

“The beauty of this place is beyond words,” Hodder wrote. “Alder Creek Grove is a suspended, mountain bowl of lush, surreal vibrancy of deep greens, of flowers of all colors, of that deep blue sierra sky that makes monstrous silhouettes of the sequoia that surround you at every turn.

Hodder is asking for the public’s help to raise the required $15.65 million by the end of the year to “fully protect this remarkable grove forever.”

“The need is urgent. If we don’t buy this property, we don’t know who will, or what they’ll do with it,” Hodder said in the post. “Walking among these trees that have been growing since the earliest human civilizations changes your understanding of the world and your place in it. We have to save this place.”

An anonymous donor has offered to match dollar-for-dollar each donation received by December 31, up to $500,000, the league said.

“This is perhaps the most significant sequoia conservation opportunity in the last 65 years,” said Becky Bremser, director of land protection for the league. “By protecting this property, we will safeguard the biological richness and ecological resilience of a forest unlike any other on Earth – with giant sequoia trees that are thousands of years old, and nearly 500 with diameters six feet or larger.”

“We also will create the opportunity for this extraordinary mountain forest to inspire the public in a truly special way,” Bremser added.

Last year, the organization bought Red Hill, one of the two largest unprotected giant sequoia forests in the world, after raising $4 million.

That 160-acre property provides a “critical habitat” for many animals, the organization said and is “one of the great natural gems of the Sierra Nevada,” Hodder added.