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Concept
Bristlecone pine
Résumé
The term bristlecone pine covers three species of pine tree (family Pinaceae, genus Pinus, subsection Balfourianae). All three species are long-lived and highly resilient to harsh weather and bad soils. One of the three species, Pinus longaeva, is among the longest-lived life forms on Earth. The oldest of this species is more than 4,800 years old, making it the oldest known individual of any species.
Despite their potential age and low reproductive rate, bristlecone pines, particularly Pinus longaeva, are usually a first-succession species, tending to occupy new open ground. They generally compete poorly in less-than-harsh environments, making them hard to cultivate. In gardens, they succumb quickly to root rot. They do very well, however, where most other plants cannot even grow, such as in rocky dolomitic soils in areas with virtually no rainfall.
Bristlecone pines grow in scattered subalpine groves at high altitude in arid regions of the Western United States. Bristlecones, along with all related species in class Pinopsida, are cone-bearing seed plants commonly known as conifers; the name comes from the prickles on the female cones.
There are three closely related species of bristlecone pines:
Great Basin bristlecone pine (Pinus longaeva) in Utah, Nevada and eastern California. The famous longest-lived species; often the term bristlecone pine refers to this tree in particular.
Rocky Mountain bristlecone pine (Pinus aristata) in Colorado, New Mexico and Arizona. The most populous species; capable of forming closed canopies and, unlike the other two, is commonly cultivated.
Foxtail pine (Pinus balfouriana) with two disjunct populations found in the Klamath Mountains (subspecies balfouriana) and the southern Sierra Nevada (subspecies austrina). A small outlying population was reported in southern Oregon, but was proven to have been misidentified. Forms the thickest groves of the three.
At least some of the three species can hybridize in cultivation, but the ranges of wild populations do not overlap.
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