Chile May Be Home to the World’s Oldest Tree

A long, long time ago, when Stonehenge was a simple earthwork enclosure and the future site of the Egyptian pyramids was nothing but wind-swept desert, a conifer sheltered in a cool, damp ravine in the Andes Mountains of South America was slowly stretching toward the sky. Today, this ancient giant holds court in Chile's Alerce Costero National Park and, according to new estimates, may take the crown as the world’s oldest tree.

“Some species do things that we think should be impossible,” Harald Bugmann, a dendrochronologist at ETH Zürich told Science.org. “There are still mysteries out there in the forest.”

This particular long-lived oddity is a Patagonian cypress (Fitzroya cupressoides), a species known for its slow growth and exceptional size. Nicknamed the Gran Abuelo tree (great-grandfather), it stands nearly 200 feet tall, features a trunk 13 feet thick, and has a perimeter of 36 feet. According to Jonathan Barichivich, a Chilean environmental scientist working at the Climate and Environmental Sciences Laboratory in Paris, the tree may be up to 5,484 years old—an age that would eclipse the current record-holder, a bristlecone pine in eastern California, by more than 600 years.

A Threatened Natural Wonder

While previous research into the age of the Gran Abuelo had estimated its age at over 3,600 years, Barichivich was determined to make a more accurate measurement and shine a brighter international spotlight on the natural wonder. Generations of his family have worked to protect the species, including his grandfather, who first discovered the Gran Abuelo in 1972. Since then, however, tourism has threatened the life of the tree, with over 10,000 people each year able to easily leave a platform surrounding its base and trample over its sensitive roots.

Speaking with Newsweek, Barichivich says only 28% of the tree remains alive, most of which is in the roots. "To me, this tree is like a family member. Seeing him like this is breaking my heart, it's like seeing a lion in a cage in a zoo," he said.

In 2020, just before the pandemic swept across the world, Barichivich and a colleague used a borer to retrieve a core sample from the tree. This process, called dendrochronology, allows researchers to count the individual growth rings present in a tree and accurately gauge its age. The Gran Abuelo is so thick, however, that the team was only able to core a 3-foot sample yielding 2,400 tightly spaced rings. To account for the missing section, they used statistical modeling and completed cores from similar trees to simulate growth rates. That process, which involved some 10,000 simulations, led to an overall estimate of 5,484 years, with an 80% chance that the tree is at least 5,000 years old. 

While that estimate is astonishing, other scientists in the field are holding back for now from fully declaring the Gran Abuelo the world’s oldest. Ed Cook, founding director of the Tree Ring Lab at Columbia University, told Science that dendrochronologically counting the rings is the “ONLY way to truly determine the age of a tree.” Others are waiting for a peer-review paper with all of the details, something Barichivich says he plans to submit in the coming months.

Whatever the outcome, however, Barichivich says there’s little doubt that the Gran Abuelo is an ancient giant deserving of both our reverence and protection for the decades or even centuries of life it may have left.

"The objective is to protect the tree, not to make headlines or break records," he told Newsweek. "It's not the point to make a big hole in the tree just to know that it's the oldest. The scientific challenge is to estimate the age without being too invasive to the tree."