To see the world's oldest tree, or one of the front-runners for world's oldest tree, one must travel to a mountaintop in Sweden where a spruce tree has kept its tenacious hold on life for nearly 10,000 years.
The spruce tree, which took root at the end of the world's last ice age in about 7542 B.C.E., was discovered by scientists surveying tree species on Fulufjället (Fulu for short) Mountain in Dalarna province in 2004. Carbon dating confirmed its age in 2008.
The type of tree — and its age — came as a surprise to Leif Kullmann, professor of Physical Geography at Sweden's Umeaa University. Kullmann led a team of researchers to a spot near the summit of Fulu Mountain, where they found a cluster of spruce trees over 8,000 years old and, among them, evidence that a single tree had existed for 9,550 years. (Kullman named the tree Old Tjikko, in honor of his late dog.)
Kullman believes that people immigrating across a land mass close to shrinking glaciers may have introduced the spruces. The discovery of the mountain spruce is not without controversy, however.
The tree's remarkable age is attributed to a single root system, which has been alive for at least four generations; the visible part of the tree — the trunk, branches, cones and needles — only lives for about 600 years. When individual tree trunks die, a cloned stem takes root to replace it.
The ability to replace a new trunk from the tree's root system has been key to its lengthy survival, say researchers.
Is a long-living clone growing from a generation-spanning root system still the same tree? It's a question scientists and researchers (and record-book publishers) will need to debate.
One thing, though, is certain: If you consider that all the world's oldest trees have lived anywhere from 5,000 to nearly 10,000 years, they are each a living example of nature's ingenuity.