Pseudotsuga menziesii var. menziesii

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Coast Douglas-fir
Douglas Firs Mount Hood National Forest.jpg
Old-growth coast Douglas-fir (Pseudotsuga menziesii var. menziesii) forest in the Mount Hood National Forest, Oregon
Scientific classification OOjs UI icon edit-ltr.svg
Kingdom: Plantae
Clade: Tracheophytes
Clade: Gymnospermae
Division: Pinophyta
Class: Pinopsida
Order: Pinales
Family: Pinaceae
Genus: Pseudotsuga
Species:
Variety:
P. m. var. menziesii
Trinomial name
Pseudotsuga menziesii var. menziesii
Synonyms [1]
List
    • Abies californicaSteud.
    • Abies douglasii(Sabine ex D.Don) Lindl.
    • Abies drummondiiGordon & Glend.
    • Abies mucronataRaf.
    • Abies mucronata var. palustrisRaf.
    • Abies obliquaBong. ex Gordon
    • Abies obliquataRaf. ex Gordon
    • Abies standishianaK.Koch
    • Abies taxifoliaC.Presl
    • Abies taxifoliaPoir.
    • Abietia douglasii(Sabine ex D.Don) A.H.Kent
    • Picea douglasii(Sabine ex D.Don) Link
    • Pinus douglasiiSabine ex D.Don
    • Pseudotsuga douglasii(Sabine ex D.Don) Carrière
    • Pseudotsuga douglasii var. pendula(Neumann) Engelm.
    • Pseudotsuga douglasii var. viridisSchwer.
    • Pseudotsuga menziesii var. viridis(Schwer.) Franco
    • Pseudotsuga menziesii subsp. viridis(Schwer.) Silba
    • Pseudotsuga taxifolia(Lindl.) Britton
    • Pseudotsuga taxifolia var. elongataLemmon
    • Pseudotsuga taxifolia var. palustris(Raf.) Lemmon
    • Pseudotsuga vancouverensisFlous
    • Tsuga douglasii(Sabine ex D.Don) Carrière

Pseudotsuga menziesii var. menziesii, commonly known as Coast Douglas-fir, Pacific 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. [2] In the Sierra Nevada it ranges as far south as the Yosemite region. It occurs from near sea level along the coast to 1,800 metres (5,900 ft) 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.

Contents

Description

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, [3] and maximum heights of 100–120 metres (330–390 ft) and diameters up to 4.5–5.5 metres (15–18 ft) have been documented. [4] :1–10 The tallest living specimen is the Doerner Fir, (previously known as the Brummit fir), 99.76 m (327 ft 4 in) tall, at East Fork Brummit Creek in Coos County, Oregon, the stoutest is the Queets Fir, 4.85 m (15 ft 11 in) diameter, in the Queets River valley, Olympic National Park, Washington. The tallest specimen ever was probably the Nooksack Giant, with a height of 142 metres as measured by tape after the tree was cut down. [5] [6] Coast Douglas-fir commonly lives more than 500 years and occasionally more than 1,000 years. [7]

Coast Douglas-fir cone, from a tree grown from seed collected by David Douglas. Note the thin 3 fingered bracts . Pseudotsuga menziesii cone.jpg
Coast Douglas-fir cone, from a tree grown from seed collected by David Douglas. Note the thin 3 fingered bracts .

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, 4–8 mm (316516 in) 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, 2–3.5 cm (341+38 in) 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. [8]

The mature female seed cones are pendent, 5–8 cm (2–3+14 in) long, 2–3 cm (341+14 in) broad when closed, opening to 4 cm (1+12 in) broad. They are produced in spring, green at first, maturing orange-brown in the autumn 6–7 months later. The seeds are 5–6 mm (31614 in) long and 3–4 mm (18316 in) broad, with a 12–15 mm (12916 in) wing. The male (pollen) cones are 2–3 cm (341+14 in) long, dispersing yellow pollen in spring. [8]

In forest conditions, old individuals typically have a narrow, cylindric crown beginning 20–40 metres (66–131 ft) 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 5 metres (16 ft) and 100 years to be clear to a height of 10 metres (33 ft). [8]

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 to 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.

Ecology

A young coast Douglas-fir stand in Anacortes Community Forest Lands, Washington Pseudotsuga menziesii 28236.JPG
A young coast Douglas-fir stand in Anacortes Community Forest Lands, Washington

The rooting habit of coast Douglas-fir is not particularly deep, with the roots tending to be shallower than those of same-aged Ponderosa pine, sugar pine, or California incense-cedar, though deeper than Sitka spruce. Some roots are commonly found in organic soil layers or near the mineral soil surface. However, Douglas-fir exhibits considerable morphological plasticity, and on drier sites coast Douglas-fir will generate deeper taproots. [8]

Douglas-fir snags are abundant in forests older than 100–150 years and provide cavity-nesting habitat for numerous forest birds. [8] Mature or "old-growth" Douglas-fir forest is the primary habitat of the red tree vole (Arborimus longicaudus) and the spotted owl (Strix occidentalis). Home range requirements for breeding pairs of spotted owls are at least 400 ha (4 square kilometres (990 acres) of old-growth. Red tree voles may also be found in immature forests if Douglas-fir is a significant component. This animal nests almost exclusively in the foliage of Douglas-fir trees. Nests are located 2–50 metres (6.6–164.0 ft) above the ground. The red tree vole's diet consists chiefly of common [9] Douglas-fir needles. A parasitic plant sometimes utilizing P. menziesii is Arceuthobium douglasii Commonly known as Douglas-fir dwarf mistletoe.

Its seedlings are not a preferred browse of black-tailed deer (Odocoileus hemionus columbianus) and elk (Cervus canadensis), but can be an important food source for these animals during the winter when other preferred forages are lacking. In many areas, coast Douglas-fir needles are a staple in the spring diet of blue grouse (Dendragapus). In the winter, New World porcupines primarily eat the inner bark of young conifers, among which they prefer Douglas-fir. [8]

Douglas-fir seeds are an extremely important food for small mammals. Mice, voles, shrews, and chipmunks consumed an estimated 65 percent of a Douglas-fir seed crop following dispersal in western Oregon. The Douglas squirrel (Tamiasciurus douglasii) harvests and caches great quantities of Douglas-fir cones for later use. They also eat mature pollen cones, developing inner bark, terminal shoots, and tender young needles. The seeds are also important in the diets of several seed-eating birds. These include most importantly American sparrows (Emberizidae) dark-eyed junco (Junco hyemalis), song sparrow (Melospiza melodia), golden-crowned sparrow (Zonotrichia atricapilla) and white-crowned sparrow (Z. leucophrys) and true finches (Fringillidae) pine siskin (Carduelis pinus), purple finch ("Carpodacus" purpureus), and the Douglas-fir red crossbill (Loxia curvirostra neogaea) which is uniquely adapted to foraging for P. menziesii seeds. [8]

The coast Douglas-fir variety is the dominant tree west of the Cascade Mountains in the Pacific Northwest, occurring in nearly all forest types, competes well on most parent materials, aspects, and slopes. Adapted to a moist, mild climate, it grows larger and faster than Rocky Mountain Douglas-fir. Associated trees include western hemlock, Sitka spruce, sugar pine, western white pine, Ponderosa pine, grand fir, coast redwood, western redcedar, California incense-cedar, Lawson's cypress, tanoak, bigleaf maple and several others. Pure stands are also common, particularly north of the Umpqua River in Oregon.

Shrub associates in the central and northern part of Coast Douglas-fir's range include vine maple (Acer circinatum), salal (Gaultheria shallon), Pacific rhododendron (Rhododendron macrophyllum), Oregon-grape (Mahonia aquifolium), red huckleberry (Vaccinium parvifolium), and salmonberry (Rubus spectabilis). In the drier, southern portion of its range shrub associates include California hazel (Corylus cornuta var. californica), oceanspray (Holodiscus discolor), creeping snowberry (Symphoricarpos mollis), western poison-oak ( Toxicodendron diversilobum ), ceanothus (Ceanothus spp.), and manzanita (Arctostaphylos spp.). In wet coastal forests, nearly every surface of old-growth coast Douglas-fir is covered by epiphytic mosses and lichens.

Forest succession

The Red Creek Fir, ca.15 km from Port Renfrew, BC, measures 43.7ft around its base and stretches 242 ft high Red Creek Fir.jpg
The Red Creek Fir, ca.15 km from Port Renfrew, BC, measures 43.7ft around its base and stretches 242 ft high

The shade-intolerance of Douglas-fir plays a large role in the forest succession of lowland old-growth forest communities of the Pacific Northwest. While mature stands of lowland old-growth forest contain many western hemlock (Tsuga heterophylla) seedlings, and some western redcedar (Thuja plicata) seedlings, Douglas-fir dominated stands contain almost no Douglas-fir seedlings. This seeming contradiction occurs because Douglas-firs are intolerant of deep shade and rarely survive for long within the shaded understory. When a tree dies in a mature forest the canopy opens up and sunlight becomes available as a source of energy for new growth. The shade-tolerant western hemlock and western redcedar seedlings that establish beneath the canopy have a head-start on other seedlings. This competitive advantage allows western hemlock to rapidly fill the canopy gap, pre-empting other species that may invade, including Douglas-fir. Long-term forest dynamics plots show that the annual mortality of large Douglas-fir is only about 1%. [10] Thus, over centuries, western hemlock and western redcedar will come to dominate the canopy.

Douglas-fir is a seral species in the wet forests of western British Columbia, Washington, Oregon, and California. In these areas, it requires a large disturbance, such as fire or a large landslide, to open the forest and expose mineral soil where its seedlings prefer to establish. [11] It has a faster growth rate than most other trees, giving the Douglas-fir a competitive advantage when it overtops slower growing species during re-establishment of the canopy. The tree ring ages of dominant Douglas-fir trees can indicate the date of the last stand-replacing fire. [12] Because Douglas-fir is long-lived, it can remain dominant in the forest for more than 300-years following the last fire. A history of fluctuating climate resulted in synchronous fire episodes across western Washington and Oregon, thus many Douglas-fir stands date to a warm-dry periods in the late 1400s and early 1500s, while few date to a cool-wet period from 1650 to 1800. [13]

Douglas-fir is also particularly well adapted to fires: once they reach around 100 years in age they have thick enough bark that protects the cambium layer of the tree from heat damage. [11] Large Douglas-fir often survive low intensity forest fires. Such sites, common in western Oregon, have two or three cohorts of Douglas-fir, adding to the complexity of the old-growth forest. [14] Fire is increasingly rare northward towards the central coast of British Columbia where Douglas-fir is a minor component of the forest.

The logging practices of the last 200 years created artificial disturbances that allowed Douglas-fir to thrive. The Douglas-fir's useful wood and its quick growth make it the crop of choice for many timber companies, which typically replant a clear-cut area with Douglas-fir seedlings. The high-light conditions that exist within a clear-cut also naturally favor the regeneration of Douglas-fir, though in wet coastal climates alders and shrubs compete with Douglas-fir seedlings. Because of clear-cut logging, almost all of the forests west of the Cascade Range not strictly set aside for protection are today dominated by Douglas-fir, while the normally dominant climax species, such as western hemlock and western redcedar are less common. On drier sites in California, where Douglas-fir behaves as a climax species in the absence of fire, Douglas-fir has become somewhat invasive following fire suppression practices of the twentieth and twenty-first centuries; it is becoming a dominant species in many oak woodlands, in which it was previously a minor component. [15]

Uses

Tree rings and heartwood Douglasie2.jpg
Tree rings and heartwood

Coast Douglas-fir is one of the world's best timber producers and yields more timber than any other tree in North America. The wood is used for dimensional lumber, timbers, pilings, and plywood. Creosote treated pilings and decking are used in marine structures. The wood is also made into railroad ties, mine timbers, house logs, posts and poles, flooring, pulp, and furniture. Coast Douglas-fir is used extensively in landscaping. It is planted as a specimen tree or in mass screenings. It is also a popular Christmas tree. [8]

Largest trees

As of 1995, coast Douglas fir was the second-tallest conifer in the world (after coast redwood). [4] :1–10 Extant coast Douglas fir trees 60–75 m (195–245 ft) or more in height and 1.5–2 m (4.9–6.6 ft) in diameter are common in old growth stands, [3] and maximum heights of 100–120 m (330–395 ft) and diameters up to 4.5–5.5 m (15–18 ft) have been documented. [4] :1–10 The tallest living specimen is the "Doerner Fir", previously known as the Brummit Fir, 99.8 m (327.3 ft) tall, [16] at East Fork Brummit Creek in Coos County, Oregon, the stoutest is the "Queets Fir", 4.85 m (15 ft 11 in) in diameter, in the Queets River valley of Olympic National Park in Washington. The largest at 349 cubic metres (12,300 cu ft) is the Red Creek fir in British Columbia, Canada.[ citation needed ] Douglas firs commonly live more than 500 years and occasionally more than 1,000 years. [17] The tallest well-documented conifer was 393 feet (120 m), the Mineral Tree (Mineral, Washington), a coast Douglas fir, measured in 1924 by Dr. Richard E. McArdle, [4] :3–4 former chief of the U.S. Forest Service. [18] The volume of that tree was 515 cubic metres (18,190 cu ft). Research suggests Douglas fir could grow to a maximum height of between 430 to 476 feet (131 to 145 m), at which point water supply would fail. [19] [20]

Unconfirmed reports of even taller individuals may be found in historic records. [21]

The tallest tree in the United Kingdom is a coast Douglas-fir. The tree, growing near Ardentinny in Scotland stands at 68.4 m (224 ft). [27]

See also

Related Research Articles

<i>Pseudotsuga</i> Genus of conifers in the family Pinaceae

Pseudotsuga is a genus of evergreen coniferous trees in the family Pinaceae. Common names for species in the genus include Douglas fir, Douglas-fir, Douglas tree, Oregon pine and Bigcone spruce. Pseudotsuga menziesii is widespread in western North America and is an important source of timber. The number of species has long been debated, but two in western North America and two to four in eastern Asia are commonly acknowledged.

<i>Pseudotsuga macrocarpa</i> Species of conifer

Pseudotsuga macrocarpa, commonly called the bigcone spruce or bigcone Douglas-fir, is an evergreen conifer native to the mountains of southern California. It is notable for having the largest cones in the genus Pseudotsuga, hence the name.

<span class="mw-page-title-main">Douglas fir</span> Species of tree

The Douglas fir is an evergreen conifer species in the pine family, Pinaceae. It is native to western North America and is also known as Douglas-fir, Douglas spruce, Oregon pine, and Columbian pine. There are three varieties: coast Douglas-fir, Rocky Mountain Douglas-fir and Mexican Douglas-fir.

<i>Pseudotsuga menziesii <span style="font-style:normal;">var.</span> glauca</i> Variety of plants

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. The range is continuous in the northern Rocky Mountains south to eastern Washington, eastern Oregon, Idaho, western and south-central Montana and western Wyoming, but becomes discontinuous further south, confined to "sky islands" on the higher mountains in Utah, Colorado, Arizona and New Mexico, with only very isolated small populations in eastern Nevada, westernmost Texas, and northern Mexico. It occurs from 600 m altitude in the north of the range, up to 3,000 m, rarely 3,200 m, in the south. Further west towards the Pacific coast, it is replaced by the related coast Douglas-fir, and to the south, it is replaced by Mexican Douglas-fir in high mountains as far south as Oaxaca. Some botanists have grouped Mexican Douglas-fir with P. menziesii var. glauca, but genetic and morphological evidence suggest that Mexican populations should be considered a different variety.

<i>Alnus rubra</i> Species of tree

Alnus rubra, the red alder, is a deciduous broadleaf tree native to western North America.

<i>Thuja plicata</i> Species of conifer

Thuja plicata is a large evergreen coniferous tree in the family Cupressaceae, native to the Pacific Northwest of North America. Its common name is western redcedar in the U.S. or western red cedar in the UK, and it is also called pacific red cedar, giant arborvitae, western arborvitae, just cedar, giant cedar, or shinglewood. It is not a true cedar of the genus Cedrus. T. plicata is the largest species in the genus Thuja, growing up to 70 metres (230 ft) tall and 7 m (23 ft) in diameter. It mostly grows in areas that experience a mild climate with plentiful rainfall, although it is sometimes present in drier areas on sites where water is available year-round, such as wet valley bottoms and mountain streamsides. The species is shade-tolerant and able to establish in forest understories and is thus considered a climax species. It is a very long-lived tree, with some specimens reaching ages of well over 1,000 years.

<span class="mw-page-title-main">Temperate rainforest</span> Forests in the temperate zone

Temperate rainforests are rainforests with coniferous or broadleaf forests that occur in the temperate zone and receive heavy rain.

<span class="mw-page-title-main">Pacific temperate rainforests</span> Temperate rainforest in the Pacific Northwest

The Pacific temperate rainforests of western North America is the largest temperate rain forest region on the planet as defined by the World Wildlife Fund. The Pacific temperate rainforests lie along the western side of the Pacific Coast Ranges along the Pacific Northwest Coast of North America from the Prince William Sound in Alaska through the British Columbia Coast to Northern California, and are part of the Nearctic realm, as also defined by the World Wildlife Fund. The Pacific temperate rain forests are characterized by a high amount of rainfall, in some areas more than 300 cm (10 ft) per year and moderate temperatures in both the summer and winter months.

<i>Arbutus menziesii</i> Species of evergreen tree

Arbutus menziesii or Pacific madrone, is a species of broadleaf evergreen tree in the family Ericaceae. It has waxy foliage, a contorted growth habit, and flaky bark.

<i>Abies grandis</i> Species of conifer tree

Abies grandis is a fir native to western North America, occurring at altitudes of sea level to 1,700 metres (5,600 ft). It is a major constituent of the Grand Fir/Douglas Fir Ecoregion of the Cascade Range.

<i>Abies concolor</i> Species of conifer tree

Abies concolor, the white fir, concolor fir, or Colorado fir, is a coniferous tree in the pine family Pinaceae. This tree is native to the mountains of western North America, including the Sierra Nevada and southern Rocky Mountains, and into the isolated mountain ranges of southern Arizona, New Mexico, and Northern Mexico. It naturally occurs at elevations between 900 and 3,400 metres.

<i>Tsuga heterophylla</i> Species of conifer

Tsuga heterophylla, the western hemlock or western hemlock-spruce, is a species of hemlock native to the west coast of North America, with its northwestern limit on the Kenai Peninsula, Alaska, and its southeastern limit in northern Sonoma County, California. The Latin species name means 'variable leaves'.

<i>Tsuga mertensiana</i> Species of tree found in western North America

Tsuga mertensiana, known as mountain hemlock, is a species of hemlock native to the west coast of North America, found between Southcentral Alaska and south-central California.

<i>Abies procera</i> Species of conifer

Abies procera, the noble fir, also called red fir and Christmas tree, is a species of fir native to the Cascade Range and Pacific Coast Ranges of the northwestern Pacific Coast of the United States. It occurs at altitudes of 300–1,500 meters (980–4,920 ft).

<span class="mw-page-title-main">Northern California coastal forests</span> Temperate coniferous forests ecoregion in northern California and southwestern Oregon

The Northern California coastal forests are a temperate coniferous forests ecoregion of coastal Northern California and southwestern Oregon.

<i>Abies amabilis</i> Species of conifer

Abies amabilis, commonly known as the Pacific silver fir, is a fir native to the Pacific Northwest of North America, occurring in the Pacific Coast Ranges and the Cascade Range. It is also commonly referred to in English as the white fir, red fir, lovely fir, amabilis fir, Cascades fir, or silver fir. The species name is Latin for 'lovely'.

<span class="mw-page-title-main">Red tree vole</span> Species of rodent

The red tree vole is a rodent of the Pacific Northwest, found in the US states of Oregon and California. They were formerly known as Phenacomys longicaudus and have also been called the red tree mouse.

<span class="mw-page-title-main">Coast Range (EPA ecoregion)</span> Coastal ecoregion in the Western United States

The Coast Range ecoregion is a Level III ecoregion designated by the Environmental Protection Agency (EPA) in the U.S. states of Washington, Oregon, and California. It stretches along the Pacific Coast from the tip of the Olympic Peninsula in the north to the San Francisco Bay in the south, including Grays Harbor, Willapa Bay, and the Long Beach Peninsula in Washington, the entire length of the Oregon Coast, and the Northern California Coast. Named for the Coast Range mountains, it encompasses the lower elevations of the Olympic Mountains, the Oregon Coast Range, the Californian North Coast Ranges, and surrounding lowlands.

<span class="mw-page-title-main">Doerner Fir</span> 100m tall Coast Douglas-fir in Oregon, US

The Doerner Fir, also known as the Brummitt Fir, is a record-setting Coast Douglas-fir in Oregon, is one of the tallest known trees in the world which is not a redwood (Sequoioideae), at 327 feet (99.7 m).

The Lynn Valley Tree was one of the tallest known Coast Douglas-fir, at a measured height of 126.5 meters (415 ft). It was cut down by the Tremblay Brothers, at Argyle Road in 1902 on the property of Alfred John Nye in Lynn Valley, now part of metropolitan Vancouver, B.C. It measured 4.34 meters (14.2 ft) across the butt, and the bark was 13.5 inches in thickness. Since that time, in the lower valley where the tree grew, the entire old-growth forest has been logged, including another tree felled in the same valley that was said to have measured 107 m tall.

References

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  2. James R. Griffin (September 1964). "A New Douglas-Fir Locality in Southern California". Forest Science: 317–319. Retrieved 2010-12-31.
  3. 1 2 McArdle, Richard E. (1930). The Yield of Douglas Fir in the Pacific Northwest. United States Department of Agriculture. Technical Bulletin No. 201. p. 7. Retrieved 17 March 2023.
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  10. Franklin, Jerry F.; DeBell, Dean S. (1988-05-01). "Thirty-six years of tree population change in an old-growth Pseudotsuga–Tsuga forest". Canadian Journal of Forest Research. 18 (5): 633–639. doi:10.1139/x88-093. ISSN   0045-5067. S2CID   36514639.
  11. 1 2 "Pseudotsuga menziesii var. menziesii". www.fs.fed.us. Retrieved 2017-10-26.
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  20. "Douglas-fir: A 350-foot-long Drinking Straw is As Long As It Gets". Oregon State University. August 11, 2008. Archived from the original on October 8, 2008.
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