By Dcrjsr - Own work, CC BY-SA 3.0, Link
Pinus longaeva (commonly referred to as the Great Basin bristlecone pine, intermountain bristlecone pine, or western bristlecone pine) is a long-living species of bristlecone pine tree found in the higher mountains of California, Nevada, and Utah. One member of this species, at 5067 years old, is the oldest known living non-clonal organism on Earth. In 1987, the bristlecone pine was designated one of Nevada's state trees.
A specimen of this species, located in the White Mountains of California was measured by Tom Harlan, a researcher with the Laboratory of Tree-Ring Research, to be 5,062 years old in 2012. The identity of the specimen is being kept secret by Harlan. This is the oldest known tree in North America, and the oldest known individual tree in the world, although a clonal individual, nicknamed "Old Tjikko", a Norway spruce in Sweden is 9,550 years old.
The previously oldest named specimen of this species, "Methuselah", is also located in the Ancient Bristlecone Pine Forest of the White Mountains. Methuselah is 4,844 years old, as measured by annual ring count on a small core has taken with an increment borer. Its exact location is also kept secret.
Among the White Mountain specimens, the oldest trees are found on north-facing slopes, with an average of 2,000 years, as compared to the 1,000 year average on the southern slopes. The climate and the durability of their wood can preserve them long after death, with dead trees as old as 7,000 years persisting next to live ones.