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''Pinus albicaulis'', whose many common names include whitebark pine, white pine, pitch pine, scrub pine, and creeping pine, occurs 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 in height, although some can reach up to . ==Characteristics== 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 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. In ''Pinus flexilis'', the cones are long, green when immature, and open to release the seeds; the scales are not fragile. Usually there are intact old cones under them. Their pollen cones are yellow. Whitebark pine (''Pinus albicaulis'') can also be hard to distinguish from western white pine (''Pinus monticola'') in the absence of cones. However, whitebark pine needles are entire (smooth when rubbed gently in either direction), whereas western white pine needles are finely serrated (feeling rough when rubbed gently from tip to base). Whitebark pine needles are also usually shorter, long, overlapping in size with the larger needles of the western white pine. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Pinus albicaulis」の詳細全文を読む スポンサード リンク
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