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{{otheruses}}
{{Taxobox
| color = lightgreen
| name = Pine
| image = Pinus pinaster.jpg
| image_width = 250px
| image_caption = Maritime Pine (''Pinus pinaster'')
| regnum = [[Plant]]ae
| divisio = [[Pinophyta]]
| classis = [[Pinophyta|Pinopsida]]
| ordo = [[Pinales]]
| familia = [[Pinaceae]]
| genus = '''''Pinus'''''
| genus_authority = [[Carolus Linnaeus|L.]]
| subdivision_ranks = Subgenera
| subdivision =
* Subgenus ''[[Pinus classification|Strobus]]''
* Subgenus ''[[Pinus classification|Ducampopinus]]''
* Subgenus ''[[Pinus classification|Pinus]]''
See '''[[Pinus classification]]''' for complete taxonomy to species level. See '''[[list of pines by region]]''' for list of species by geographical distribution.
}}

A '''pine''' is a [[Pinophyta|coniferous]] [[tree]] in the [[genus]] '''''Pinus''''', in the [[family (biology)|family]] [[Pinaceae]]. They make up the [[monotypic]] [[subfamily]] '''Pinoideae'''. There are about 115 [[species]] of pine, although different authors accept anything from 105 to 125 species.

==Distribution==
Pines are native to most of the [[Northern Hemisphere]]. In [[Eurasia]], they range from the [[Canary Islands]] and [[Scotland]] east to the [[Russia|Russian Far East]], and the [[Philippines]], north to just over 70°N in [[Norway]] ([[Scots Pine]]) and eastern [[Siberia]] ([[Siberian Dwarf Pine]]), and south to northernmost [[Africa]], the [[Himalaya]] and [[Southeast Asia]], with one species ([[Sumatran Pine]]) just crossing the [[Equator]] in [[Sumatra]] to 2°S. In [[North America]], they range from 66°N in [[Canada]] ([[Jack Pine]]) south to 12°N in [[Nicaragua]] ([[Caribbean Pine]]). The highest diversity in the genus occurs in [[Mexico]] and [[California]].

Pines have been introduced in subtropical and temperate portions of the [[Southern Hemisphere]], including [[Chile]], [[Brazil]], [[Australia]], and [[New Zealand]], where they are grown widely as a source of timber, and some are becoming [[invasive species]].

==Morphology==
[[Image:Pinus pinea.jpg|thumb|left|Juvenile (left) and adult foliage of [[Stone Pine]] (''Pinus pinea''); note dark brown scale leaves as well as needles on adult shoot]]
Pines are [[evergreen]] and [[resin]]ous [[tree]]s (rarely [[shrub]]s) growing to 3–80 m tall, with the majority of species reaching between 15-45 m tall. The smallest are [[Siberian Dwarf Pine]] and [[Potosi Pinyon]], and the tallest, [[Sugar Pine]]. Pines are long-lived, typically reaching ages of 100–1,000 years, and some even longer; the longest-lived is [[Great Basin Bristlecone Pine]], where one individual at 4,839 years (2007) is the [[List of long-living organisms|oldest living organism]] in the world.

The [[bark]] of most pines is thick and scaly, but some species have thin, flaking bark. The branches are produced in regular "pseudowhorls", actually a very tight [[spiral]] but appearing like a ring of branches arising from the same point. Many pines are ''uninodal'', producing just one such whorl of branches each year, from [[bud]]s at the tip of the year's new [[plant stem|shoot]], but others are ''multinodal'', producing two or more whorls of branches per year. The spiral growth of branches, needles and cone scales are arranged in [[Fibonacci number]] ratios. The new spring shoots are sometimes called "candles"; they are covered in brown or whitish bud scales and point upward at first, then later turn green and spread outward. These "candles" offer [[forester]]s a means to evaluate [[fertility]] of the soil and vigour of the trees.

===Foliage===
Pines have four types of [[leaf|leaves]]:
#''Seed leaves'' ([[cotyledon]]s) on seedlings, borne in a whorl of 4-24.
#''Juvenile leaves'', which follow immediately on seedlings and young plants, 2-6 cm long, single, green or often blue-green, and arranged spirally on the shoot. These are produced for six months to five years, rarely longer (and also produced later in life after injury in some pines).
#''Scale leaves'', similar to bud scales, small, brown and non-photosynthetic, and arranged spirally like the juvenile leaves.
#''Needles'', the adult leaves, which are green ([[photosynthetic]]), bundled in clusters (''fascicles'') of (1-) 2-5 (-6) needles together, each fascicle produced from a small [[bud]] on a dwarf shoot in the axil of a scale leaf. These bud scales often remain on the fascicle as a basal sheath. The needles persist for 1.5-40 years, depending on species. If a shoot is damaged (e.g. eaten by an animal), the needle fascicles just below the damage will generate a bud which can then replace the lost growth.

===Cones===
[[Image:Pineflower9538.jpg|left|thumb|[[Loblolly Pine]] (''Pinus taeda''): male cones]]
[[Image:Pine cone edit.jpg|right|thumb|A fully mature [[Monterey Pine]] cone on the forest floor.]]
Pines are mostly [[Plant sexuality|monoecious]], having the male and female [[Conifer cone|cones]] on the same tree, though a few species are [[Plant sexuality|sub-dioecious]] with individuals predominantly, but not wholly, single-sex. The male cones are small, typically 1-5 cm long, and only present for a short period (usually in spring, though autumn in a few pines), falling as soon as they have shed their [[pollen]]. The female cones take 1.5-3 years (depending on species) to mature after [[pollination]], with actual fertilization delayed one year. At maturity the cones are 3-60 cm long. Each cone has numerous spirally arranged scales, with two seeds on each fertile scale; the scales at the base and tip of the cone are small and sterile, without seeds. The seeds are mostly small and winged, and are anemophilous (wind-dispersed), but some are larger and have only a vestigial wing, and are [[bird]]-dispersed (see below). At maturity, the cones usually open to release the seeds, but in some of the bird-dispersed species (e.g. [[Whitebark Pine]]), the seeds are only released by the bird breaking the cones open. In others, the ''fire climax pines'' (e.g. [[Monterey Pine]], [[Pond Pine]]), the seeds are stored in closed ("serotinous") cones for many years until a forest fire kills the parent tree; the cones are also opened by the heat and the stored seeds are then released in huge numbers to re-populate the burnt ground.

==Classification==
Pines are divided into three subgenera, based on cone, seed and leaf characters:
* Subgenus ''[[Pinus classification|Strobus]]'' (white or soft pines). Cone scale without a sealing band. Umbo terminal. Seedwings adnate. One fibrovascular bundle per leaf.
* Subgenus ''[[Pinus classification|Ducampopinus]]'' (pinyon, lacebark and bristlecone pines). Cone scale without a sealing band. Umbo dorsal. Seedwings articulate. One fibrovascular bundle per leaf.
* Subgenus ''[[Pinus classification|Pinus]]'' (yellow or hard pines). Cone scale with a sealing band. Umbo dorsal. Seedwings articulate. Two fibrovascular bundles per leaf.

==Ecology==
[[Image:Dead pines.jpg|thumb|left|[[Mountain pine beetle]]s killed these [[Lodgepole Pine]]s in [[Prince George, British Columbia]].]]
Pines grow well in acid [[soil]]s, some also on calcareous soils; most require good soil drainage, preferring sandy soils, but a few, e.g. [[Lodgepole Pine]], will tolerate poorly drained wet soils. A few are able to sprout after forest fires, e.g. [[Canary Island Pine]]. Some species of pines, e.g. [[Bishop Pine]], need fire to regenerate and their populations slowly decline under fire suppression regimes. Several species are adapted to extreme conditions imposed by elevation and latitude; see e.g. [[Siberian Dwarf Pine]], [[Mountain Pine]], [[Whitebark Pine]] and the [[bristlecone pine]]s. The [[pinyon pine]]s and a number of others, notably [[Turkish Pine]], are particularly well adapted to growth in hot, dry [[desert|semi-desert]] climates.

The [[seed]]s are commonly eaten by [[bird]]s and [[squirrel]]s. Some birds, notably the [[Spotted Nutcracker]], [[Clark's Nutcracker]] and [[Pinyon Jay]], are of importance in distributing pine seeds to new areas where they can grow. Pine needles are sometimes eaten by some [[Lepidoptera]] species (see [[list of Lepidoptera which feed on Pines]]) and also the [[Symphyta]]n species [[Pine Sawfly]].

==Uses==
[[Image:Young pine trees.jpg|thumb|Commercial planting of young Longleaf Pine (Pinus palustris)]]
Pines are commercially among the most important of species used for [[timber]] and [[wood pulp]] in temperate and tropical regions of the world. This is because they are fast-growing [[softwood]]s that can be planted in relatively dense stands, and because their acidic decaying needles may inhibit the growth of other competing plants in the cropping areas. Commercial pine crops are grown in [[plantation]]s.

The [[resin]] of some species is important as the source of [[turpentine]]. See also [[Pitch (resin)|pitch]].

Many pines are also very attractive ornamental trees planted in [[park]]s and large [[garden]]s. A large number of dwarf [[cultivar]]s have been selected, suitable for planting in smaller gardens. Some pines are also used for [[Christmas tree]]s, and pine cones are also widely used for Christmas decorations. Pine trees are also noted for their pleasant smell.

Pine needles serve as food for various [[Lepidoptera]]. See [[List of Lepidoptera which feed on Pines]].

===Food uses===
[[Image:umbrella.pine.in.rome.arp.jpg|thumb|right|[[Stone Pine]] ''Pinus pinea'' in a [[Rome]] ([[Italy]]) street]]
{{main|Pine nut}}
Some species have large [[seed]]s, called [[pine nut]]s, that are harvested and sold for cooking and baking.

The soft, moist, white inner bark ([[vascular cambium|cambium]]) found clinging to the woody outer [[bark]] is edible and very high in vitamins [[vitamin A|A]] and [[vitamin C|C]]. It can be eaten raw in slices as a snack or dried and ground up into a powder for use as a thickener in stews, soups, and other foods{{Fact|date=August 2007}}. A tea made by steeping young, green pine needles in boiling water (known as "tallstrunt" in Sweden) is high in vitamins A and C as well.

==Etymology==
The modern [[English language|English]] name ''pine'' derives from [[Latin]] ''Pinus'' by way of [[French language|French]] ''pin''; similar names are used in other [[Romance languages]]. In the past (pre-19th century) they were often known as ''fir'', from [[Old Norse language|Old Norse]] ''fyrre'', by way of [[Middle English]] ''firre''. The Old Norse name is still used for pines in some modern north European languages, in [[Danish language|Danish]], ''fyr'', in [[Norwegian language|Norwegian]] and [[Swedish language|Swedish]], ''furu'', and ''Föhre'' in [[German language|German]], but in modern English, "fir" is now restricted to [[Fir]] (''Abies'') and ''[[Douglas-fir]] (''Pseudotsuga'').

==References==
{{Commons|Pinus}}
{{refbegin}}
* Farjon, A. 1984, 2nd edition 2005. ''Pines''. E. J. Brill, Leiden. ISBN 90-04-13916-8
* Little, E. L., Jr., and Critchfield, W. B. 1969. ''Subdivisions of the Genus Pinus (Pines)''. US Department of Agriculture Misc. Publ. 1144 (Superintendent of Documents Number: A 1.38:1144).
* Richardson, D. M. (ed.). 1998. ''Ecology and Biogeography of Pinus''. Cambridge University Press, Cambridge. 530 p. ISBN 0-521-55176-5
* Mirov, N. T. 1967. ''The Genus Pinus''. Ronald Press, New York (out of print).
* [http://www.pinetum.org/Lovett/classification.htm Classification of pines]
* [http://www.conifers.org/pi/pin/index.htm Gymnosperm Database - Pinus]
{{refend}}

{{Pinaceae}}

[[Category:Pinaceae]]
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