In the Alerce Costero National Park in Chile, there is a very large, very old tree. Alerce trees do not live fast and die young. They grow extremely slowly and live for a very, very long time. As originally mentioned in Science, Jonathan Barichivich says the Alerce Milenario is the oldest tree of all: probably at least 5,000 years old, right after the Bronze Age. This is much older than the previous record holder, a hairy pine in eastern California believed to be 4,853 years old.
Barichivich is an environmental scientist who grew up on his family’s land in front of the park, and in the midst of his passion for other climate science issues, has dedicated his life to studying and protecting wildlife trees.
Alerce Milenario is the largest tree in the rainforest. Because alerce trees grow so slowly, it was suspected that the tree was extremely old because it was so large, with a trunk diameter of over 13 feet.
Such a large tree became a tourist attraction for the park. After investing in road infrastructure in 2012 that improved accessibility, Barichivich said the park has more than 10,000 visitors a year, all of whom wanted to see the Alerce Milenario. There is a platform that surrounds the roots of the tree, but it is not well guarded or underlined, so people often climb off the platform and walk over the roots. The only problem, Barichivich said, is that the tree is very vulnerable. Only 28 percent of the tree is actually alive, most of which is at the roots, so when people walk on nearby ground, they actively destroy the last remaining living parts of the tree.
“To me, this tree is like a family. Seeing it that way breaks my heart, it’s like seeing a lion in a cage at a zoo,” Barichivich said. Newsweek. His family members call themselves guardians of the fields and generations before him were park rangers dedicated to protecting the land and trees. As an environmentalist, the best thing he could do for trees is to prove how important they were to science and that they deserved to be protected.
Usually, the age of a tree is measured using dendrochronology. A perforator is inserted into the core of the trunk and the number of growth rings present corresponds to how old it is. However, the Alerce Milenario is too wide for the typical 2.9-foot punch to reach the inner core, and Barichivich said trees that are often so old have a rotten core anyway. Another option is to use root piercing and date them with carbon, but that would damage the roots, and that’s the last thing Barichivich wants to do.
“The goal is to protect the tree, not to make headlines or break records,” he said. “It does not make sense to make a big hole in the tree just to know that it is the oldest. The scientific challenge is to estimate the age without being too invasive in the tree.”
To measure waking age without destroying it, Barichivich and Antonio Lara, of the Australian University of Chile, used a statistical modeling approach to predict the age of trees based on their knowledge of how they grow when they are young, creating a Bayesian. distribution of the possible age of a given tree using data from 2,400 trees.
Barichivich’s estimated age for Alerce Milenario was 5,484 years. It can be said with almost certainty that the tree is at least 5,000 years old.
As its data and methods have not yet been officially published, there is skepticism in the scientific community about this result, especially since it is a record-breaking prediction.
Baricivic does not mind him. “Alerce is the second longest-lived species, so one would expect to see old trees. My method is verified by studying other trees that can get full growth rings and follow a biological law of growth-longevity trade. Vigilance is where you will “It had to be on the exponential growth curve: it grows slower than the pine, the oldest known tree, which shows that it has to live longer,” he said.
Barichivich hopes his methods can work toward a future tree research where dendrochronology would harm a vulnerable tree like Alerce Milenario, and that his discoveries about his family’s respected tree would push the park authorities to do more to protect the gentle giant.