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Old Tjikko is a 9,550 year old Norway Spruce tree, located on Fulufjället Mountain of Dalarna province in Sweden. Old Tjikko is the world's oldest living individual clonal tree, however, there are many examples of much older clonal colonies (multiple trees connected by a common root system), such as "Pando", estimated to be over 80,000 years old. The age of the tree was determined by carbon dating of the root system under the tree, not by dendrochronology, or counting tree rings. The trunk itself is estimated to be only a few hundred years old, but the tree as a whole may have 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). The oldest living non-clonal tree, verified by dendrochronology, is "Methuselah" (4,800 years old), a Great Basin Bristlecone Pine in California. Vegetative cloning and reproduction is common in many plants, such as the creosote bush (see "King Clone", estimated from growth rate to be almost 12,000 years old). Many other plants also may take advantage of this process either exclusively or in tandem with sexual reproduction, but dating or estimating the age of these organisms may not be possible without evidence (e.g., old roots, ancient remains, consistent growth rates).