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{{Unreferenced|date=January 2007}}
{{Otheruses}}
{{Taxobox
| color = lightgreen
| name = Pear
| image = Pears.jpg
| image_caption = [[European Pear]] branch with fruit
| regnum = [[Plant]]ae
| divisio = [[Flowering plant|Magnoliophyta]]
| classis = [[Magnoliopsida]]
| ordo = [[Rosales]]
| familia = [[Rosaceae]]
| subfamilia = [[Maloideae]]
| genus = '''''Pyrus'''''
| genus_authority = [[Carolus Linnaeus|L.]]
| subdivision_ranks = [[Species]]
| subdivision =
About 30 species; see text
}}
A '''pear''' is a [[tree]] of the [[genus]] ''Pyrus'' and the juicy [[fruit]] of that tree, edible in some species. The English word ''pear'' is probably from Common [[West Germanic]] ''*pera'', probably a loanword of [[Vulgar Latin]] ''pira'', the plural of ''pirum'', which is itself of unknown origin. See also [[Peorð]]. The [[Perry (disambiguation)|place name ''Perry'']] can indicate the historical presence of pear trees. The term "pyriform" is sometimes used to describe something which is "pear-shaped".
The pear is classified within [[Maloideae]], a subfamily within [[Rosaceae]]. The [[apple]] (''Malus ''×''domestica'') which it resembles in floral structure, is also a member of this subfamily. In both cases the so-called fruit is composed of the receptacle or upper end of the flower-stalk (the so-called [[calyx (botany)|calyx]] tube) greatly dilated, and enclosing within its cellular flesh the five [[cartilaginous]] [[carpels]] which constitute the "core" and are really the true fruit. From the upper rim of the receptacle are given off the five [[sepal]]s, the five [[petal]]s, and the very numerous [[stamen]]s. Another major relative of the pear (and thus the apple) is the [[quince]].
The form of the pear and of the apple respectively, although usually characteristic enough, is not by itself sufficient to distinguish them, for there are pears which cannot by form alone be distinguished from apples, and apples which cannot by superficial appearance be recognized from pears. A major distinction is the occurrence in the tissue of the fruit, or beneath the rind, of clusters of lignified cells known as "grit" in the case of the pear, while in the apple no such formation of woody cells takes place. The appearance of the tree—the bark, the foliage, the type of inflorescence (i.e. form of the flower cluster) —is, however, usually quite characteristic in the two species.
The genus is thought to have originated in present-day western China in the foothills of the Tian Shan Mountains, and to have spread to the east and west along mountain chains, evolving into a diverse group of over 20 widely recognized primary species. The cultivated European pear (''Pyrus communis'')''', '''whose number is enormous, are without doubt derived from one or two wild species (''P. pyraster'' and ''P. caucasica'''''), '''widely distributed throughout Europe, and sometimes forming part of the natural vegetation of the forests. In [[England]], where the pear is sometimes considered wild, there is always the doubt that it may not really be so, but the produce of some seed of a cultivated tree deposited by birds or otherwise, which has degenerated into wild spine-bearing trees. Asian species with medium to large edible fruit include ''P. pyrifolia'', ''P. ussuriensis'', ''P. ×bretschneideri'', ''P. ×sinkiangensis'', and ''P. pashia.'' Other small-fruited species are frequently used as rootstocks for the cultivated species.
The cultivation of the pear extends to the remotest antiquity. Traces of it have been found in the Swiss lake-dwellings; it is mentioned in the oldest Greek writings, and was cultivated by the Romans. The word "pear" or its equivalent occurs in all the Celtic languages, while in Slavonic and other dialects different appellations, but still referring to the same thing, are found–a diversity and multiplicity of nomenclature which led [[Alphonse de Candolle]] to infer a very ancient cultivation of the tree from the shores of the Caspian to those of the Atlantic. A certain race of pears, with white down on the under surface of their leaves, is supposed to have originated from ''P. nivalis'', and their fruit is chiefly used in France in the manufacture of [[Perry]] (see [[Cider]]). Other small-fruited pears, distinguished by their precocity and apple-like fruit, may be referred to ''P. cordata'', a species found wild in western [[France]], and in [[Devon|Devonshire]] and [[Cornwall]]. Pears have been cultivated in China for approximately 3000 years.
==Botany==
Pears are native to coastal and mildly temperate regions of the [[Old World]], from western [[Europe]] and north [[Africa]] east right across [[Asia]]. They are medium sized trees, reaching 10-17 m tall, often with a tall, narrow crown; a few species are [[shrub]]by. The [[leaf|leaves]] are alternately arranged, simple, 2-12 cm long, glossy green on some species, densely silvery-hairy in some others; leaf shape varies from broad oval to narrow lanceolate. Most pears are [[deciduous]], but one or two species in southeast Asia are [[evergreen]]. Most are cold-hardy, withstanding temperatures between −25 °C and −40 °C in winter, except for the evergreen species, which only tolerate temperatures down to about −15 °C.
The [[flower]]s are white, rarely tinted yellow or pink, 2-4 cm diameter, and have five petals. Like that of the related [[apple]], the pear fruit is a [[pome]], in most wild species 1-4 cm diameter, but in some cultivated forms up to 18 cm long and 8 cm broad; the shape varies in most species from oblate or globose, to the classic pyriform '[[pear shaped|pear-shape]]' of the [[European Pear]] with an elongated basal portion and a bulbous end.
The pear is very similar to the [[apple]] in cultivation, [[Fruit tree propagation|propagation]] and [[Fruit tree pollination|pollination]].
There are about 30 primary species, major subspecies, and naturally occurring interspecific hybrid of pears.
===Major recognized taxa===
{|
|- valign=top
|
*''[[Pyrus amygdaliformis]]'' – Almond-leafed Pear
*''[[Pyrus armeniacifolia]]''
*''[[Pyrus betulifolia]]''
*''[[Pyrus boissieriana]]''
*''[[Pyrus ×bretschneideri]]'' - Chinese white pear; also classified as a subspecies of ''Pyrus pyrifolia''
*''[[Callery Pear|Pyrus calleryana]]'' – Callery Pear
*''[[European Pear|Pyrus communis]]'' – European Pear
*''Pyrus communis '' subsp. ''caucasica''
*''Pyrus communis'' subsp. ''pyraster'' - Wild European Pear
*''[[Pyrus cordata]]'' – Plymouth Pear
*''[[Pyrus cossonii]]'' – Algerian Pear
*''[[Pyrus dimorphophylla]]''
*''[[Pyrus elaeagrifolia]]'' – Oleaster-leafed Pear <!--[[tr:Pyrus elaeagrifolia]]-->
*''[[Pyrus fauriei]]''
*''[[Pyrus gharbiana]]''
*''[[Pyrus glabra]]''
*''Pyrus hondoensis''
*''[[Pyrus koehnei]]'' - Evergreen pear of southern China and Taiwan
*''[[Pyrus korshinskyi]]''
*''[[Pyrus mamorensis]]''
*''[[Pyrus nivalis]]'' – Snow Pear
*''[[Pyrus pashia]]'' – Afghan Pear
*''[[Pyrus ×phaeocarpa]]''
*''[[Pyrus pseudopashia]]''
*''[[Nashi Pear|Pyrus pyrifolia]]'' – Nashi Pear, Sha Li
*''[[Pyrus regelii]]''
*''[[Pyrus salicifolia]]'' – Willow-leafed Pear
*''[[Pyrus ×serrulata]]''
*''[[Pyrus ×sinkiangensis]]'' - thought to be an interspecific hybrid between ''P. ''×''bretschneideri'', ''Pyrus ussuriensis'' and ''Pyrus communis''
*''[[Pyrus syriaca]]''
*''[[Pyrus ussuriensis]]'' – Siberian Pear, Chinese fragrant pear
*''[[Pyrus xerophila]]''
|}
[Note: Species names preceded by "×" indicate an interspecific hybrid species.]
==Cultivation==
<!-- <br clear="all"> -->
{{nutritionalvalue | name=Pear, raw | kJ=242 | protein=0.38 g | fat=0.12 g | carbs=15.46 g | fiber=3.1 g | | sugars=9.80 g | iron_mg=0.17 | calcium_mg=9 | magnesium_mg=7 | phosphorus_mg=11 | potassium_mg=119 | zinc_mg=0.10 | vitC_mg=4.2 | pantothenic_mg=0.048 | vitB6_mg=0.028 | folate_ug=7 | thiamin_mg=0.012 | riboflavin_mg=0.025 | niacin_mg=0.157 | right=1 | source_usda=1 }}
The pear may be readily raised by sowing the pips of ordinary cultivated or of wilding kinds, these forming what are known as free or pear stocks, on which the choicer varieties are [[grafted]] for increase. For new varieties the flowers should be fertilized with a view to combine, in the seedlings which result from the union, the desirable qualities of the parents.
===Grafting===
The dwarf and pyramid trees of the European pear, more usually planted in gardens, are obtained by grafting on the quince stock, the Quince A, C, or Provence quince being the best; but these rootstocks, from their surface-rooting habit, are most suitable for soils of a cold damp nature. These trees will be 50 to 70 percent of the size of trees on common pear roostock, will bear fruit earlier, increase yield, and, in some cases, increase fruit size. Some of the finer pears do not unite readily with the quince, and in this case double working is resorted to; that is to say, a graft-compatible pear, usually 'Old Home' or 'Buerre Hardy' is first grafted on the quince, and then the choicer pear is grafted on the pear introduced as its foster parent. Several cultivars, including the prized 'Doyenne du Comice', are compatible directly on quince. Common pear rootstock (''P. communis''), having an inclination to send its roots down deeper into the soil, is the best for light dry soils, as the plants are not then so likely to suffer in dry seasons. Seedling rootstocks have been replaced with clonally propagated rootstocks, including the 'Old Home' × 'Farmingdale' series, 'Pyriam', and others. While generally, not as dwarfing as quince, some of these rootstocks will reduce tree size to 60 to 80 percent of a standard tree on seedling rootstock.
===Planting Young Trees===
In selecting young pear trees for walls or espaliers, some persons prefer plants one year old from the graft, but trees two or three years trained are equally good. The trees should be planted immediately before or after the fall of the leaf. The wall trees require to be planted from 25 to 30 ft. apart when on free stocks, and from 15 to 20 ft. when dwarfed. Where the trees are trained as pyramids or columns they may stand 8 or 10 ft. apart, but standards in orchards should be allowed at least 30 ft., and dwarf bush trees half that distance.
In the formation of the trees the same plan may be adopted as in the case of the apple. For the pear orchard a warm situation is very desirable, with a soil deep, substantial, and thoroughly drained. Any good free loam is suitable, but a calcareous loam is the best. Pear trees worked on the quince should have the stock covered up to its junction with the graft. This is effected by raising up a small mound of rich compost around it, a contrivance which induces the graft to emit roots into the surface soil.
===Training and Pruning===
The fruit of the pear is produced on spurs, which appear on shoots more than one year old. The mode most commonly adopted of training wall pear-trees is the horizontal. For the slender twiggy sorts the fan form is to be preferred, while for strong growers the half-fan or the horizontal is more suitable. In the latter form old trees, the summer pruning of which has been neglected, are apt to acquire an undue projection from the wall and become scraggy, to avoid which a portion of the old spurs should be cut out annually.
The summer pruning of established wall or [[espalier]]-rail trees consists chiefly in the timely displacing, shortening back, or rubbing off of the superfluous shoots, so that the winter pruning, in horizontal training, is little more than adjusting the leading shoots and thinning out the spurs, which should be kept close to the wall and allowed to retain but two or at most three buds. In fan-training the subordinate branches must be regulated, the spurs thinned out, and the young laterals finally established in their places. When horizontal trees have fallen into disorder, the branches may be cut back to within 9 in. of the vertical stem and branch, and trained in afresh, or they may be grafted with other sorts, if a variety of kinds is wanted.
[[Image:2005pear_and_quince.PNG|300px|thumb|left|Pear and [[quince]] output in 2005]]
===Harvest===
Summer and autumn pears should be gathered before they are fully ripe, while they are still green, but snap off when lifted. If left to ripen and turn yellow on the tree, the sugars will turn to starch crystals and the pear will have gritty texture inside. The 'Jargonelle' should be allowed to remain on the tree and be pulled daily as wanted, the fruit from standard trees thus succeeding the produce of the wall trees. In the case of the 'Passe Crassane', long the favored winter pear in France, the crop should be gathered at three different times, the first a fortnight or more before it is ripe, the second a week or ten days after that, and the third when fully ripe. The first gathering will come into eating latest, and thus the season of the fruit may be considerably prolonged. It is evident that the same method may be followed with other sorts which continue only a short time in a mature state.
===Diseases and pests===
{{Main|List of pear diseases}}
{{main|List of Lepidoptera which feed on Pear trees}}
==Uses==
[[Image:Bradford 9288.JPG|right|thumb|[[Callery Pear]]s in flower]]
Three species account for the vast majority of edible fruit production, the [[European Pear]] ''Pyrus communis'' cultivated mainly in Europe and [[North America]], the Chinese white pear (bai li) ''Pyrus ×bretschneideri'', and the [[Nashi Pear]] ''Pyrus pyrifolia'' (also known as Asian Pear or Apple Pear), both grown mainly in eastern Asia. There are thousands of [[cultivar]]s of these three species. A species grown in western China, ''P. sinkiangensis'', and ''P. pashia'', grown in southern China and south Asia, are also produced to a lesser degree.
Other species are used as [[rootstock]]s for European and Asian pears and as [[ornamental plant|ornamental trees]]. The [[Siberian Pear]], ''Pyrus ussuriensis'' (which produces unpalatable fruit) has been crossed with ''Pyrus communis'' to breed hardier pear cultivars. The [[Callery Pear|Bradford Pear]] (''Pyrus calleryana'' 'Bradford') in particular has become widespread in North America and is used only for decoration. The [[Willow-leafed Pear]] (''Pyrus salicifolia'') is grown for its attractive slender, densely silvery-hairy leaves. <br clear = left>
Pears are consumed fresh, canned, as [[juice]], and [[dried fruit|dried]]. The juice can also be used in [[Jelly (fruit preserves)|jellies]] and [[jam]]s, usually in combination with other fruits or berries. Fermented pear juice is called [[perry]].
Pears will ripen faster if placed next to [[banana]]s in a fruit bowl. They stay fresh for longer if kept in a [[fridge]].
Pears are the least [[allergenic]] of all fruits. Along with [[lamb]] and [[soya]] formula, pears form part of the strictest exclusion diet for allergy sufferers.
Pear [[wood]] is one of the preferred materials in the manufacture of high-quality [[woodwind]] instruments and [[furniture]]. It is also used for wood carving, and as a [[firewood]] to produce aromatic smoke for smoking meat or [[tobacco]].
In some Eastern cultures, pears are also known as the fruit of planning. People who consume pears are believed to have superior organizational skills.
==References==
{{1911}}
==External links==
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|{{Wiktionary}}
|}
{| align="right" cellspacing="0" cellpadding="0" style="clear:right; margin-bottom: .5em; float: right; padding: .5em 0 .8em 1.4em; background: none;"
|{{Commons2|Pear}}
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|{{Cookbook|Pear}}
|}
* [http://www.usapears.com/pears/varieties.asp USA Pears] - descriptions of pear cultivars from a U.S. advocacy group.
* [http://www.uga.edu/fruit/pear.html University of Georgia Pear Page] - History of cultivation and commerce.
[[Category:Maloideae]]
[[Category:Pears| ]]
[[Category:Flora of Asia]]
[[Category:Flora of Europe]]
[[Category:Symbols of Oregon]]
[[Category:Fruit]]
