The Great Basin Bristlecone Pines, or Pinus longaeva, is a long-living species of tree found in the higher mountains of the southwest United States. Bristlecone pines grow in isolated groves in the arid mountain regions of six western states of America, but the oldest are found in the Ancient Bristlecone Pine Forest in the White Mountains of California. These trees have a remarkable ability to survive in extremely harsh and challenging environment. In fact, they are believed to be the some of oldest living organisms in the world, with lifespans in excess of 5,000 years.

Bristlecone pines grow just below the tree line, between 5,000 and 10,000 feet of elevation. At these great heights, the wind blows almost constantly and the temperatures can dip to well below zero. The soil is dry receiving less than a foot of rainfall a year. Because of these extreme conditions, the trees grow very slowly, and in some years don't even add a ring of growth. Even the tree's needles, which grow in bunches of five, can remain green for forty years.

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