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Whitebark Pine
Pinus albicuaulis
Engelm.

Located on Lolo Trail 16 Sep 1905. (Source)

Whitebark pine is a slow growing, long-lived, ectomycorrhizal, native conifer characteristic of tree line. Trees often reach 400 to 700 years of age.  Growing at the uppermost limits of growth, trees usually are dwarfed or contorted. At upper tree line this species takes on a spreading krummholz growth form and grows in isolated cushions of "alpine scrub" 1 to 3 feet. The largest reported whitebark pine in the United States is in the Sawtooth Range of central Idaho and is 69 feet in height and 9.5 feet in d.b.h.  Whitebark pine trees commonly have two or more trunks that are often partially fused at the base. Two or more trunks of what appears to be a single tree are indeed separate trees with distinct genotypes. Several mature trees can arise from single seed caches and that seeds cached by Clark's nutcrackers are instrumental in the establishment of trees. Trees develop a deep and spreading root system on most sites.

Whitebark pine grows on dry rocky sites on high mountains between 6,000 and 10,000 feet (1,800 and 3,030 m). Whitebark pine is an important component of high-elevation forests in Idaho, Montana, and Wyoming between 5,900 and 10,500 feet. Trees occur on dry rocky, subalpine slopes, and exposed ridges. Stands are generally open with an undergrowth of low shrubs, forbs, and grasses. Sites where whitebark pine occurs as a climax are drier than those where it is seral. Whitebark pine is important in areas where the mean annual precipitation is 24 to 70 inches. The climate is characterized by cool summers and cold winters with deep snowpack. Trees have high frost resistance and low shade tolerance. (Source)

Food Uses:
The inner bark is sweet flavored and edible in the spring. Young needles are steeped for tea.  The seeds are oil rich and nutritious and were eaten by Native Americans and early settlers. The cones were burned to release the seeds, which were then eaten, ground into meal for making breads and stored for later use. 

Medicinal Uses:
Young needles are a source for vitamin C. Pine needle tea was used to treat fevers and coughs.  The resin is used for cough syrups and ointments for burns and skin infections. 


Value for Animals:
Whitebark pine is a valuable source of food and cover for wildlife. Bears, rodents, and birds consume the seeds. The trunks provide nesting sites for cavity nesters including northern flickers and mountain bluebirds. Blue grouse use the branches for roosting and escape cover.

Whitebark pine ecosystems provide critical habitat for grizzly and black bears.  Whitebark pine seeds are a high-quality bear food. Red and Douglas' squirrels provide an important ecological link between whitebark pine and bears by making the seeds more readily available.  Bear consumption of whitebark pine seed peaks just before hibernation in late October and early November. Bears feeding on whitebark pine seeds tend to feed on nothing else, and a good supply of seeds increases bear fecundity. In Yellowstone National Park, female grizzly bears were less likely to abort, and more likely to have larger litters (3 cubs compared to 1-2 cubs) in good conecrop years. Most importantly, grizzly bear death rate was nearly double when bear consumption of whitebark pine seeds was low.  In Yellowstone National Park, grizzly bear summer and fall movement is related to availability of whitebark pine seed. 

Whitebark pine is a minor browse species for big game, but whitebark pine under stories often provide valuable forage. Rocky Mountain mule deer consume trace amounts of whitebark pine. Many bird species use whitebark pine ecosystems. Whitebark pine provides ecologically critical linkage between Clark's nutcracker and lower-elevation, Clark's nutcracker-dependant pines. (Source)


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