Common Names
Rocky Mountain bristlecone pine.

Habitat
isolated groves at & just below tree-line. In Arizona, found only on the San Francisco Peaks. Common on south and southwest facing slopes above 10,500 feet.

Description
Varies from large and well-formed trees to stunted and windblown. Leaves in bundles of 5 with small resin blisters common on the edges of the leaves. When immature, cones have a small bristle that protrudes from the umbo of the scale. Bark becomes thick and furrowed when mature, lending some fire resistance.

Comments
One species reaches an age far more significant than any other single living organism known, up to nearly 5,000 years. As the tree ages, much of its bark may die; in ancient specimens, often only a narrow strip of living tissue connects the roots to the handful of live branches. Though this species can reach great ages, the oldest are in the drier great basin, and it is not likely that Arizona has many if any specimens over 1000 years in age. This is due to our relatively warm moist summers, which allow for soil pathogens to impact the roots of the older, less vigorous individuals.