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{{Taxobox
| color = green
| name = Douglas-fir
| image = Pseudotsuga_menziesii_28236.JPG
| image_width = 250px
| image_caption = ''Pseudotsuga menziesii'' subsp. ''menziesii'' in [[Anacortes Community Forest Lands]], [[Washington]]
| regnum = [[Plant]]ae
| divisio = [[Pinophyta]]
| classis = [[Pinophyta|Pinopsida]]
| ordo = [[Pinales]]
| familia = [[Pinaceae]]
| genus = '''''Pseudotsuga'''''
| genus_authority = [[Elie-Abel Carrière|Carrière]]
| subdivision_ranks = Species
| subdivision = See text
}}

'''Douglas-fir''' is the common name applied to [[Pinophyta|coniferous]] [[tree]]s of the [[genus]] ''Pseudotsuga'' in the family [[Pinaceae]]. There are five species, two in western [[North America]], one in [[Mexico]] and two in eastern [[Asia]]. The Douglas-firs gave 19th century botanists problems due to their similarity to various other conifers better known at the time; they have at times been classified in [[pine|''Pinus'']], [[spruce|''Picea'']], [[fir|''Abies'']], ''[[Tsuga]]'', and even [[Coast Redwood|''Sequoia'']]. Because of the distinctive cones, Douglas-firs were finally placed in the new genus ''Pseudotsuga'' (meaning "false [[Tsuga]]") by the [[France|French]] botanist [[Elie-Abel Carrière|Carrière]] in 1867.

The common name honours [[David Douglas]], the [[Scotland|Scottish]] [[botanist]] who first introduced the tree into cultivation in 1826. Douglas is known for introducing many North American native conifers to [[Europe]]. The [[hyphen]] in the common name indicates that Douglas-firs are not true firs; i.e. they are not members of the genus ''Abies''.<ref>{{cite book|last=Little|first=E. L.|date=1953|title=Check List of native and naturalized trees of the United States (including Alaska)|id=USDA Agricultural Handbook 41|publisher=U.S. Department of Agriculture|location=Washington D.C.}}</ref>

The Douglas-firs are medium-size to large or very large [[evergreen]] [[tree]]s, to 20-100 m tall. The [[leaf|leaves]] are flat and needle-like, generally resembling those of the [[fir]]s. The female [[Conifer cone|cones]] are pendulous, with persistent scales (unlike true firs), and are distinct in having a long tridentine (three-pointed) [[bract]] that protrudes prominently above each scale.

Douglas-firs are used as food plants by the [[larva]]e of some [[Lepidoptera]] species including [[Autumnal Moth]], [[Bordered White]], [[Engrailed|The Engrailed]], [[Pine Beauty]], [[Turnip Moth]] and the [[Gelechiidae|gelechiids]] ''[[Chionodes|Chionodes abella]]'' and ''[[Chionodes|Chionodes periculella]]'' which have both been recorded on ''P. menziesii''.

A Californian [[Native Americans in the United States|Native American]] myth explains that each of the three-ended bracts are a tail and two tiny legs of the [[mouse|mice]] who hid inside the scales of the tree's cones, which was kind enough to be the enduring sanctuary for them during forest fires.

==Species and varieties==
[[Image:Pseudotsuga menziesii cone.jpg|thumb|[[Coast Douglas-fir]] cone, from a tree grown from seed collected by [[David Douglas]]]]
By far the best-known is the very widespread and abundant [[North America]]n species ''Pseudotsuga menziesii'', a taxonomically complex species<ref>{{cite journal|first=Peng|last=Li|coauthors=W. T. Adams|title=Rangewide patterns of allozyme variation in Douglas-fir|quotes=no|journal=Canad. J. Forest Res.|volume=19|pages=149-161|date=1989}}</ref> divided into two major subspecies (treated as distinct species by some botanists); [[Coast Douglas-fir]] or 'Green Douglas-fir', on the [[Pacific]] coast; and [[Rocky Mountain Douglas-fir]] or 'Interior Douglas-fir', in the interior west of the continent. The latter is in turn divided into two varieties, 'Blue Douglas-fir' or 'Colorado Douglas-fir' (var. ''glauca'') in the southern Rocky Mountains, and 'Gray Douglas-fir' or 'Fraser River Douglas-fir' (var. ''caesia'') in the northern Rocky Mountains. The species as a whole is generally known as simply 'Douglas-fir', or as 'Common Douglas-fir'; other less widely used names include 'Oregon Douglas-fir', 'Douglas Tree', and 'Oregon Pine'. It can attain heights of 100 m (330 ft), second only to the [[Coast Redwood]] (old claims of trees up to 126 m (415 ft) have never been verified), and is the [[List of U.S. state trees|state tree]] of [[Oregon]]. The specific name, ''menziesii'', is after [[Archibald Menzies]], a Scottish physician and rival [[Natural history|naturalist]] to [[David Douglas]], who first discovered the tree on [[Vancouver Island]] in 1791. Away from its native area, it is also extensively used in [[forestry]] as a [[plantation]] tree for [[timber]] in [[Europe]], [[New Zealand]], southern [[South America]] and elsewhere. It is also [[naturalisation (biology)|naturalised]] in Ireland and Britain, [[Chile]] and [[New Zealand]], sometimes to the extent of becoming an [[invasive species]] subject to control measures.

[[Image:Douglas Fir branch-750px.JPG|right|thumb|Coast Douglas-fir branch]]
[[Image:Pseudotsuga 01.jpg|right|thumb|Rocky Mountain Douglas-fir twig]]
[[Image:Douglas Fir buds.jpg|right|frame|The buds of a Coast Douglas-fir]]
All of the other species are of restricted range and little-known outside of their respective native environments, and even there are often rare and only of very scattered occurrence, occurring in mixed forests; all are listed as being of unfavourable [[conservation status]].

;North America
* [[Coast Douglas-fir]], ''Pseudotsuga menziesii'' subsp. ''menziesii''
** [[Rocky Mountain Douglas-fir]], ''Pseudotsuga menziesii'' subsp. ''glauca''
* [[Mexican Douglas-fir]], ''Pseudotsuga lindleyana''
* [[Bigcone Douglas-fir]], ''Pseudotsuga macrocarpa''

;Asia
* [[Japanese Douglas-fir]], ''Pseudotsuga japonica''
* [[Chinese Douglas-fir]], ''Pseudotsuga sinensis'' var. ''sinensis''
** [[Chinese Douglas-fir|Narrow-cone Chinese Douglas-fir]], ''Pseudotsuga sinensis'' var. ''gaussenii''
** [[Chinese Douglas-fir|Short-leaf Chinese Douglas-fir]], ''Pseudotsuga sinensis'' var. ''brevifolia''
** [[Chinese Douglas-fir|Yunnan Douglas-fir]], ''Pseudotsuga sinensis'' var. ''forrestii''
** [[Chinese Douglas-fir|Taiwan Douglas-fir]], ''Pseudotsuga sinensis'' var. ''wilsoniana''

== Uses ==
Douglas-fir [[wood]] is used for structural applications that are required to withstand high loads. It is used extensively in the construction industry. Other examples include its use for homebuilt [[aircraft]]. Very often, these aircraft were designed to utilise [[Sitka Spruce]], which is getting increasingly difficult to source in aviation quality grades.
Douglas-fir were also formerly bought as more unconventional Christmas trees. Their scraggly appearance has led them to be less desirable, however, and they are now much harder to find.{{Fact|date=September 2007}}

==Diseases==
{{Main|List of douglas-fir diseases}}

==Trivia==
* The tallest tree in the [[United Kingdom]] is a Douglas-fir (''Pseudotsuga menziesii''). The tree, growing in Reelig Glen by [[Inverness]] is called Dughall Mor and stands at 64 m. It was measured in 2005 by Tony Kirkham and Jon Hammerton from the [[Royal_Botanic_Gardens%2C_Kew|Royal Botanic Gardens, Kew]], the late Jim Paterson from [[The Tree Register]] and David Jardine of [[Forestry_Commission|The Forestry Commission]].<sup>[3]</sup>

*On [[May 14]] [[2001]], a Douglas-fir was planted in honor of [[Douglas Adams]] after his death on [[May 11]] [[2001]]. They are also sometimes planted on [[Towel Day]].

==References==
{{reflist}}
* <sup>[3]</sup> The Trees That Made Britain, BBC Wales.

==External links==
{{commons|Pseudotsuga}}
* [http://www.pinetum.org/cones/PScones.htm Arboretum de Villardebelle - cone photos] Images of cones of selected species
* [http://www.conifers.org/pi/ps/index.htm Gymnosperm Database]
* [http://www.forestry.gov.uk/forestry/INFD-6UELAN Dughall Mor at Forestry Commission]
* [http://www.tree-register.org/ The Tree Register]

{{Pinaceae}}

[[Category:Pinaceae]]
[[Category:Trees_of_Northwestern_United_States]]

Douglas-fir - Revision history

MediaWiki default at 12:35, 5 November 2007