When it comes to old trees, the Western U.S. can’t be beat. There are bristlcone pines in the Great Basin over 4,000 years old, giant sequoias that have survived since 1,000 B.C. and coast redwoods that were saplings when Julius Caesar was a boy.
But in Europe, trees that reach 1,000-years-old are a rarity. So the discovery of a Bosnian pine tree (Pinus heldreichii) that is at least 1,075-years-old is a big deal. It stands in a grove in the Pindus Mountains of northern Greece along with of a dozen other pines at or close to the millennia mark. The tree, dubbed Adonis, is believed to be the oldest living tree in Europe.
“It is quite remarkable that this large, complex and impressive organism has survived so long in such an inhospitable environment, in a land that has been civilized for over 3,000 years,” Paul Krusic a member of the expedition that found the tree says in a press release.
Krusic and his team weren’t looking for Europe’s oldest tree, reports Rachel Feltman for The Washington Post. Instead, they were looking to collect tree-ring data from older trees to help track changes in climate. They took a core sample from Adonis, using a method that does not permanently injure the tree. And when they began counting rings, they realized they had a very old piece of wood on their hands. They counted a total of 1,075 rings, but since the core didn't reach the center of the tree and was taken relatively high up its trunk, they expect it to be even older.
There are trees in Europe that are millennia older than Adonis, but they are clonal—reproducing asexually from the same ancient root system. Their trunks and top growth, however, occasionally die back so they are usually only a couple hundred years old. Examples of clonal trees include aspen, spruce and some species of pine. One notorious example is Old Tjikko, a Norway spruce discovered in Sweden in 2004. Its trunk is only about 600 years old, but its root system is over 9,500 years old. Elsewhere, clonal trees can get even older. For instance, Pando, an Aspen clone in Utah, has 47,000 trees connected to its root system and is at least 80,000 years old, though its individual stems or trunks don't live more than a couple hundred years.
Although not clonal, yew trees can also push the limits of arboreal age. The Fortingall Yew in Perthshire, Scotland, is believed to be between 2,000 to 5,000 years old. But this tree's growth pattern also differs from Adonis' single ancient trunk. Yew trees put up fresh shoots that eventually merge with the main trunk, creating buttresses that hold the tree up even if the main trunk dies. The heartwood of the Fortingall Yew decayed centuries ago, making it difficult to get a precise estimate of its age.
“The tree we have stumbled across is a unique individual,” Krusic tells Feltman. “It cannot rely on a mother plant, or the ability to split or clone itself, to survive. Cloning is a very effective evolutionary survival strategy. It’s cool, but it’s not the same. It’s not the same as you or I being left alone to our own devices and living for 1,000 years, like this tree.”
Krusic caught wind of the ancient grove while reading a thesis about the Pindus pine forest a few years ago. The photos of the stunted, gnarled trees reminded him of the ancient bristlecone pines found in the U.S. Southwest and he began to harbor suspicions that these trees were very old. Turns out his hunch was right. Krusic hopes to continue studying both the living and dead trees in the forest, which could contain valuable climate data.
Krusic points out that it’s amazing these trees were never harvested. Though in a remote area of the mountains, it is still very close to areas where humans have lived for thousands of years. “I am impressed, in the context of western civilization, all the human history that has surrounded this tree; all the empires, the Byzantine, the Ottoman, all the people living in this region,” he says in the press release. “So many things could have led to its demise. Fortunately, this forest has been basically untouched for over a thousand years.”