Old Tjikko

Old Tjikko is an approximately 9,568-year-old Norway spruce, located in the Dalarna province in Sweden. Old Tjikko originally gained fame as the "world's oldest tree". Old Tjikko is, however, a clonal tree that has regenerated new trunks, branches and roots over millennia rather than an individual tree of great age. Old Tjikko is recognized as the oldest living Picea abies and the fourth-oldest known clonal tree.

The age of the tree was determined by carbon dating of genetically matched plant material collected from under the tree, as dendrochronology does not work for clonal trees. The trunk itself is estimated to be only a few centuries old, but the plant has survived for much longer due to a process known as layering (when a branch comes in contact with the ground, it sprouts a new root), or vegetative cloning (when the trunk dies but the root system is still alive, it may sprout a new trunk).

Discovery and details

The root system of Old Tjikko is estimated to be 9,568 years old, making it the world's oldest known Norway spruce. It stands 5 metres (16 ft) tall and is located on Fulufjället Mountain of Dalarna province in Sweden. For millennia, the tree appeared in a stunted shrub formation (also known as a krummholz formation) due to the harsh extremes of the environment in which it lives. During the warming of the 20th century, the tree sprouted into a normal tree formation. The husband and wife who discovered the tree, Leif Kullman (professor of physical geography at Umeå University), and Lisa Öberg (tree scientist with a doctorate in biology and ecology from Mid Sweden University) attributed this growth spurt to global warming and named the tree "Old Tjikko", after their late dog.