Conservation Save the Redwoods League group (SRL) has closed a $15.65 million deal to buy the largest privately owned giant sequoia grove left on Earth. Due to its size, health and age diversity.  

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, a century-old California nonprofit that's been working to acquire Alder Creek for more than 20 years.

SRL plans to eventually transfer ownership to the US Forest Service, so the sequoias can join the federally protected wilderness around them, but that won't happen for a while since SRL expects to hold the property for 5-10 years to study the grove and implement a plan for good stewardship, ensuring the trees are healthy and ready before handing them over to the public.