Pinus albicaulis Whitebark pine |
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A stand of whitebark pines at Crater Lake National Park, Oregon | |
Scientific classification | |
Kingdom: | Plantae |
Division: | Pinophyta |
Class: | Pinopsida |
Order: | Pinales |
Family: | Pinaceae |
Genus: | Pinus |
Subgenus: | Strobus |
Species: | P. albicaulis |
Binomial name | |
Pinus albicaulis Engelm. |
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Natural range of Pinus albicaulis | |
Synonyms | |
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Pinus albicaulis, whose many common names include whitebark pine, white pine, pitch pine, scrub pine, and creeping pine, grows in the mountains of the western United States and Canada, specifically the subalpine areas of the Sierra Nevada, the Cascade Range, the Pacific Coast Ranges, and the Rocky Mountains from Wyoming northwards. It shares the common name creeping pine with several other "creeping pine" plants.
The whitebark pine is typically the highest-elevation pine tree of these mountains, marking the tree line. Thus, it is often found as krummholz, trees dwarfed by exposure and growing close to the ground. In more favourable conditions, trees may grow to up to 29 meters (95 ft) in height.
Whitebark pine (Pinus albicaulis) is a member of the white pine group, Pinus subgenus Strobus, section Strobus and like all members of that group, the leaves ('needles') are in fascicles (bundles) of five, with a deciduous sheath. This distinguishes whitebark pine and relatives from the lodgepole pine (Pinus contorta), with two needles per fascicle, and ponderosa pine (Pinus ponderosa) and Jeffrey pine (Pinus jeffreyi), which both have three per fascicle; these three all also have a persistent sheath at the base of each fascicle.
Distinguishing whitebark pine (Pinus albicaulis), from the related limber pine (Pinus flexilis), also a "white pine", is much more difficult, and needs seed or pollen cones. In Pinus albicaulis, the cones are 4–7 centimeters (1.6–2.8 in) long, dark purple when immature, and do not open on drying, but the scales easily break when they are removed by Clark's nutcracker (see below) to harvest the seeds; rarely are there intact old cones under them. Its pollen cones are scarlet.