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Douglas-fir is one of the world's best timber-producing species and yields more timber than any other species in North America, making the forestlands of western Oregon, Washington, and British Columbia the most productive on the continent. In 2011, Douglas-fir represented 34.2% of US lumber exports, to a total of 1.053 billion board-feet.
Pseudotsuga / ˌ sj uː d oʊ ˈ t s uː ɡ ə / [1] is a genus of evergreen coniferous trees in the family Pinaceae (subfamily Laricoideae).Common names for species in the genus include Douglas fir, Douglas-fir, Douglas tree, Oregon pine and Bigcone spruce.
Coast Douglas-fir is the second-tallest conifer in the world (after coast redwood), and the third-tallest of all trees, (after Eucalyptus regnans).Currently, coast Douglas-fir trees 60–75 metres (197–246 ft) or more in height and 1.5–2 metres (4.9–6.6 ft) in diameter are common in old growth stands, [4] and maximum heights of 100–120 metres (330–390 ft) and diameters up to 4.5–5. ...
Pseudotsuga menziesii var. glauca, or Rocky Mountain Douglas-fir, is an evergreen conifer native to the interior mountainous regions of western North America, from central British Columbia and southwest Alberta in Canada southward through the United States to the far north of Mexico. [2]
[citation needed] PSL can be made from any wood species, but Douglas fir, southern pine, western hemlock, and yellow poplar are commonly chosen [9] because of their superior strength. The product is manufactured as a 12-by-12-inch (300 mm × 300 mm) or 12-by-18-inch (300 mm × 460 mm) billet in a rectangular cross-section, which is then ...
Timber design or wood design is a subcategory of structural engineering that focuses on the engineering of wood structures. Timber is classified by tree species (e.g., southern pine, douglas fir, etc.) and its strength is graded using numerous coefficients that correspond to the number of knots, the moisture content, the temperature, the grain ...
Some hybrids of Pseudotsuga macrocarpa (Bigcone Douglas-fir) × Pseudotsuga menziesii (Coast Douglas-fir) show promise for planting on drier restoration sites within the P. menziesii−Douglas-fir natural range. These hybrids produce wood of comparable quality to that of Douglas-fir and have the drought tolerance of bigcone Douglas-fir.
Pseudotsuga menziesii var. lindleyana, commonly known as the Mexican Douglas-fir, is a conifer in the genus Pseudotsuga that is endemic to Mexico. [1] DNA sequence [2] and morphological [3] evidence suggests it is most closely related to Rocky Mountain Douglas-fir (P. menziesii var. glauca) and might best be treated as an additional variety within P. menziesii.