Bristlecone pine

There are two related species. The Rocky Mountain bristlecone pine (Pinus aristata) is found in Utah and Colorado, and specimens have been found up to 3,000 years old.

The recordholder, however, is the Great Basin bristlecone pine (Pinus longaeva). One of them, named "Prometheus", was cut down in 1964, in the area now protected by Great Basin National Park in Nevada. Its rings were counted (not easy because the trunks are very twisted and distorted), and was determined to be about 4,900 years old. Currently, the oldest living bristlecone, Methuselah, is believed to be about 4,700 years old, although there are certainly older specimens in remote areas of Nevada.

Prometheus did not die just to have its rings counted. The carbon content of the wood from its various rings was analyzed, thus providing an important calibration for radiocarbon dating.

Bristlecones grow in isolated groves just below treeline. Between cold temperatures, high winds, and short seasons, the trees grow very slowly. The wood is very dense and thus resistant to invasion by insects, fungi, etc. As the tree ages, much of its bark dies, typically leaving only a few strips to connect the roots to the handful of live branches.