Why mystery surrounds what may be Earth’s oldest tree

What might be the world’s oldest tree – a bristlecone pine named Methuselah that is thousands of years old – is hidden in plain sight somewhere along the 4.5-mile Methuselah Trail in the Inyo National Forest in California. Even photos of it are rare – the internet is littered with pictures of old and gnarled bristlecone pines mislabeled as Methuselah.

More than a half-century of word of mouth, amplified in recent years by the internet, has eroded the secret of Methuselah’s location in the Eastern Sierras. Yet uncertainty persists, even among some experts.

Maintaining as much mystery as possible has become essential to keeping overenthusiastic tourists away from Methuselah and trees like it. But tourists aren’t the only threat – the West’s worst drought in more than 1,200 years has killed bristlecone pines near Methuselah, while bark beetles are threatening other ancient bristlecone.

These trees have survived hot and dry periods in the past, said Constance Millar, a scientist emerita at the U.S. Forest Service. But she worries human-induced climate change could create a “perfect storm” of threats to some of them with extreme heat, drought and an increased risk of forest fires.

Generally, tree age is determined by taking core samples with boring tools that remove a piece of the tree about the diameter of a pencil, which researchers can use to count tree rings.

In 1957, after gathering initial cores from Methuselah, Edmund Schulman, then a scientist at the Laboratory of Tree-Ring Research, estimated that the gnarled bristlecone pine was more than 4,600 years old. He also found that relatively small bristlecone pines – most of the ones Schulman studied were only 10 to 30 feet tall – were older than giant sequoias, which previously had been thought to be the longest-living trees.

Salzer recently re-examined Schulman’s Methuselah cores and got a count close to 4,600 years, although some rings were difficult to tally. Reportedly, a core from Methuselah with more rings visible was later found in the laboratory’s tree core archive, but Salzer and colleagues have not been able to find it. This has led to confusion about Methuselah’s age. Wikipedia and many other sites and publications list it as 4,854 years old, but the basis for that age is the rumored “missing” core, which has never been scientifically documented.

Across the globe, there are legends of trees older than Methuselah, including Iran’s Sarv-e Abarkuh and the Llangernyw Yew in Wales, both rumored to be between 4,000 and 5,000 years old. The estimates are based primarily on local lore and have not been verified.

Then there are clonal trees, genetically identical trees that share a root system such as Sweden’s Old Tjikko and the Pando colony of aspens in Utah. Although these trees have root systems older than the oldest trees, the trees themselves are clones and generally much younger than Methusaleh and other ancients.

In the archive of the Laboratory of Tree-Ring Research, a core sample from an unnamed tree gathered by Schulman in the 1950s was found years later to be more than 4,800 years old. A more recent challenger to Methuselah’s claim has emerged in Chile, where researchers estimate that a massive and famous alerce or Patagonian Cypress tree called Alerce Milenario, or Gran Abuelo (great-grandfather), is 5,400 years old.

Because the tree is more than 12 feet in diameter, the researchers obtained only a partial core sample, but they determined that the tree is at least 2,400 years old based on its tree rings. They then used tree-ring information from other old alerces and computer modeling to calculate an additional 3,000 years.

The tree-ring record contained in old bristlecones has helped scientists refine carbon dating and provides an important history of the Earth’s climate. The trees might also offer insight into the aging process.

There is urgency to these protection efforts, as Alerce Milenario has long been a tourist destination. Visitors walking around the tree in recent years have damaged its roots. “The tree is in a really, really bad state,” Barichivich said. “It’s like a lion in a cage in a zoo.”

Barichivich’s concern for the tree’s health is part of what makes determining its age without models difficult. Although existing coring tools are too small to get to the center of a tree the size of Alerce Milenario, a longer tool could be custom manufactured. But Barichivich, who is Chilean, does not want to do this out of fear of harming the tree.

His grandfather discovered the tree in the 1970s, and his grandparents, mother and uncle worked in the park where it lives. Barichivich sees himself as a third-generation protector of the tree and identifies with the Indigenous Mapuche people and their concept of the “spirit of the forest.”

Tales of otherworldly protection also surround bristlecone pines. Stories of a curse began after several bristlecone pine researchers, Schulman included, died young. Schulman suffered a stroke and passed away at 49.

Salzer is skeptical of such tales, but acknowledged: “It is useful from a preservation point of view to say, ‘Don’t mess with the trees or you’ll be cursed.’ ”