The Limber Pine, of the family Pinaceae and the genus Pinus, is an evergreen gymnosperm native to the Rocky Mountains of Western U.S. and Canada. Limber pines range from 7-12 m in height and 60-90 cm in diameter; they have needle-shaped, dark-green leaves, light-gray bark that becomes red-brown with age, and resinous, flexible branches. They thrive in subalpine habitats (10,000 to 11,500 feet in elevation), but are remarkably adaptable due to their tolerance to cold and drought. They are monoecious, with clustered yellow-brown staminate cones and woody, deep-brown ovulate cones that give rise to winged seeds. The seeds (pine nuts) and inner bark of Limber Pines are food sources for various animals, most notably nutcrackers and squirrels, who in turn aid in seed distribution. The branches of the Limber Pines also serve as a habitat for various animals and rodents, providing protection from predators and adverse weather conditions. Limber Pines can take several hundred years to reach maturity and can live for over 1000 years. Though Limber Pines are evergreen, fertilization of ovulate cones only occurs in late spring, and seed dispersal mainly occurs in the fall. Though Limber Pine wood is not suitable for commercial timber harvesting, its timber has been used for cabins, fencing, mining, and firewood. Limber Pines bear pine nuts, which have a wide variety of culinary applications in foods like pesto, salads, granola, and various baked goods. Not factoring in human activity, the greatest risk to Limber Pine populations is disease: both white pine blister rust (a common fungal disease in pines) and dwarf mistletoe (Arceuthobium Cyanocarpum) are leading causes of Limber Pine mortality.
