Limber pine

Description

Pinus flexilis, the limber pine, is a species of pine tree-the family Pinaceae that occurs in the mountains of the Western United States, Mexico, and Canada. It is also called Rocky Mountain white pine. A limber pine in Eagle Cap Wilderness, Oregon has been documented as over 2,000 years old, and another one was confirmed at 1140 years old. Another candidate for the oldest limber pine was identified in 2006 near the Alta Ski Area in Utah; called "Twister", the tree was confirmed to be at least 1,700 years old and thought to be even older. Its pliant branches gives it the common name "limber" and specific epithet flexilis. Its needles are about 8 centimeters (3+1⁄4 in) long and a dark, blueish green. Its bark is heavily creased and dark grey. Its pale wood is lightweight and soft. Pinus flexilis is typically a high-elevation pine, often marking the tree line either on its own, or with whitebark pine (Pinus albicaulis), either of the bristlecone pines, or lodgepole pine (Pinus contorta). In favorable conditions, it makes a tree to 20 metres (65 feet), rarely 25 m (80 ft) tall. On exposed tree line sites, mature trees are much smaller, reaching heights of only 5–10 m (15–35 ft). In steeply-sloping, rocky, and windswept terrain in the Rocky Mountains of southern Alberta, limber pine is even more stunted, occurring in old stands where mature trees are consistently less than 3 m (10 ft) in height. One of the world's oldest living limber pine trees grows on the banks of the upper North Saskatchewan River at Whirlpool Point in Alberta. Recent measurements give a maximum girth of 185". In 1986, a core sample 10 cm was retrieved by two researchers who counted 400 rings. Extrapolating his data gives an age close to 3,000 years.