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''Pseudotsuga menziesii'' var. ''menziesii'', also known as coast Douglas-fir, Oregon pine, or Douglas spruce, is an evergreen conifer native to western North America from west-central British Columbia, Canada southward to central California, United States. In Oregon and Washington its range is continuous from the Cascades crest west to the Pacific Coast Ranges and Pacific Ocean. In California, it is found in the Klamath and California Coast Ranges as far south as the Santa Lucia Mountains with a small stand as far south as the Purisima Hills, Santa Barbara County. In the Sierra Nevada it ranges as far south as the Yosemite region. It occurs from near sea level along the coast to in the California Mountains. Further inland, coast Douglas-fir is replaced by Rocky Mountain or interior Douglas-fir (''P. menziesii'' var. ''glauca''). Interior Douglas-fir intergrades with coast Douglas-fir in the Cascades of northern Washington and southern British Columbia. ==Description== Coast Douglas-fir is currently the second-tallest conifer in the world (after coast redwood), and the third-tallest of all trees (after that and Eucalyptus regnans). Currently, coast Douglas-fir trees or more in height and in diameter are common in old growth stands, and maximum heights of and diameters up to have been documented. The tallest living specimen is the "Doerner Fir", (previously known as the Brummit fir), tall, at East Fork Brummit Creek in Coos County, Oregon, the stoutest is the "Queets Fir", diameter, in the Queets River valley, Olympic National Park, Washington. Coast Douglas-fir commonly lives more than 500 years and occasionally more than 1,000 years.〔(Gymnosperm Database: ''Pseudotsuga menziesii'' var. ''menziesii'' (2006) )〕 The bark on young trees is thin, smooth, gray, and contains numerous resin blisters. On mature trees, it is thick and corky.〔 The shoots are brown to olive-green, turning gray-brown with age, smooth, though not as smooth as fir shoots, and finely pubescent with short dark hairs. The buds are a very distinctive narrow conic shape, long, with red-brown bud scales. The leaves are spirally arranged but slightly twisted at the base to lie in flattish either side of the shoot, needle-like, long, green above with no stomata, and with two whitish stomatal bands below. Unlike the Rocky Mountain Douglas-fir, coast Douglas-fir foliage has a noticeable sweet fruity-resinous scent,〔 particularly if crushed. The mature female seed cones are pendent, long,〔 broad when closed, opening to broad. They are produced in spring, green at first, maturing orange-brown in the autumn 6–7 months later. The seeds are long and broad, with a wing. The male (pollen) cones are long, dispersing yellow pollen in spring. In forest conditions, old individuals typically have a narrow, cylindric crown beginning above a branch-free trunk. Self-pruning is generally slow and trees retain their lower limbs for a long period. Young, open-grown trees typically have branches down to near ground level. It often takes 70–80 years for the trunk to be clear to a height of and 100 years to be clear to a height of . Appreciable seed production begins at 20–30 years in open-grown coast Douglas-fir. Seed production is irregular; over a 5-7 year period, stands usually produce one heavy crop, a few light or medium crops, and one crop failure. Even during heavy seed crop years, only about 25 percent of trees in closed stands produce an appreciable number of cones. Each cone contains around 25 to 50 seeds. Seed size varies; average number of cleaned seeds varies from 70-88/g (32,000-40,000 per pound). Seeds from the northern portion of coast Douglas-fir's range tend to be larger than seed from the south. 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「Pseudotsuga menziesii var. menziesii」の詳細全文を読む スポンサード リンク
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