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PEAR (Pyrus communis)

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Originally appearing in Volume V21, Page 24 of the 1911 Encyclopedia Britannica.
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PEAR (Pyrus communis) , a member of the natural See also:order See also:Rosaceae, belonging to the same genus as the See also:apple (P.See also:malus), which it resembles in floral structure. In both cases the so-called See also:fruit is composed of the receptacle or upper end of the See also:flower-stalk (the so-called calyx See also:tube) greatly dilated, and en-closing 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 sepals, the five petals, and the very numerous stamens. The See also:form of the pear and of the apple respectively, although usually characteristic enough, is not by itself sufficient to distinguish them, for there are See also:pears which cannot by form alone be distinguished from apples, and apples which cannot by superficial See also:appearance be recognized from pears. The See also:main distinction is the occurrence in the See also:tissue of the fruit, or beneath the rind, of clusters of cells filled with hard woody See also:deposit in the See also:case of the pear, constituting the " grit," while in the apple no such formation of woody cells takes See also:place. The appearance of the See also:tree—the bark, the foliage, the See also:flowers—is, however, usually quite characteristic in the two See also:species. Cultivated pears, whose number is enormous, are without doubt derived from one or two See also:wild species widely distributed throughout See also:Europe and western See also:Asia, and sometimes forming See also:part of the natural vegetation of the forests. In See also: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 See also:seed of a cultivated tree deposited by birds or otherwise, which has degenerated into the wild spine-bearing tree known as Pyrus communis. The cultivation of the pear extends to the remotest antiquity. Traces of it have been found in the Swiss See also:lake-dwellings; it is mentioned in the See also:oldest See also:Greek writings, and was cultivated by the See also:Romans. The word " pear " or its See also:equivalent occurs in all the See also:Celtic See also:languages, while in See also:Slavonic and other dialects different appellations, but still referring to the same thing, are found—a diversity and multiplicity of nomenclature which led See also:Alphonse de See also:Candolle to infer a very See also:ancient cultivation of the tree from the shores of the See also:Caspian to those of the See also:Atlantic. A certain See also:race of pears, with See also:white down on the under See also:surface of their leaves, is supposed to have originated from P. nivalis, and their fruit is chiefly used in See also:France in the manufacture of See also:Perry (see See also:CIDER).

Other small-fruited pears, distinguished by their precocity and apple-like fruit, may be referred to P. See also:

cord ata, a species found wild in western France, and in See also:Devonshire and See also:Cornwall. Karl See also:Koch considered that cultivated pears were the descendants of three species—P. persica (from which the bergamots have descended), P. elaeagrifolia and P. sinensis. J. Decaisne, who made the subject one of See also:critical study for a number of years, and not only investigated the wild forms, but carefully studied the peculiarities of the numerous varieties cultivated in the Jardin See also:des Plantes at See also:Paris, refers all cultivated pears to one species, the individuals of which have in course of See also:time diverged in various directions, so as to form now six races: (I) the Celtic, including P. cordata; (2) the Germanic, including P. communis, P. achras, and P. piraster; (3) the Hellenic, including P. parviflora, P. sinaica and others; (4) the Pontic, including P. elaeagrifolia; (5) the See also:Indian, comprising P. Paschae; and (6) the Mongolic, represented by P. sinensis. With reference to the Celtic race, P. cordata, it is interesting to See also:note its connexion with Arthurian See also:legend and the Isle of See also:Avalon or Isle of Apples. An See also:island in See also:Loch See also:Awe has a Celtic legend containing the See also:principal features of Arthurian See also:story; but in this case the word is " berries " instead of " apples." Dr Phone visited See also:Armorica (See also:Brittany) with a view of investigating these matters, and brought thence fruits of a small See also:berry-like pear, which were identified with the Pyrus cordata of western France. Cultivation.—The pear may be readily raised by See also:sowing the pips of See also:ordinary cultivated or of wilding kinds, these forming what are known as See also:free or pear See also: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 See also:union, the desirable qualities of the parents. The See also:dwarf and See also:pyramid trees, more usually planted in gardens, are obtained by grafting on the See also:quince stock, the See also:Portugal quince being the best; but this stock, from its surface-rooting See also:habit, is most suitable for soils of a See also:cold See also:damp nature. The pear-stock, having an inclination to send its roots down deeper intc the See also:soil, is the best for See also:light dry soils, as the See also:plants are not then so likely to suffer in dry seasons. Some of the finer pears do not unite readily with the quince, and in this case See also:double working is resorted to; that is to say, a vigorous-growing pear is first grafted on the quince, and then the choicer pear is grafted on the pear introduced as its See also:foster See also:parent.

In selecting See also:

young pear trees for walls or espaliers, some persons prefer plants one See also:year old from the See also:graft, but trees two or three years trained are equally See also:good. The trees should be planted immediately before or after the fall of the See also:leaf. The See also: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 ro ft. apart, but See also:standards in orchards should be allowed at least 30 ft., and dwarf See also:bush trees See also:half that distance. In the formation of the trees the same See also:plan may be adopted as in the case of the apple. For the pear See also:orchard a warm situation is very desirable, with a soil deep, substantial, and thoroughly drained. Any good free See also: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 See also:mound of See also:rich compost around it, a contrivance which induces the graft to emit roots into the surface soil, and also keeps the stock from becoming hard or bark-See also:bound. 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 See also:horizontal. For the slender twiggy sorts the See also: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 See also:

apt to acquire an undue See also: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 See also:espalier-See also:rail trees consists chiefly in the timely displacing, shortening back, or rubbing off of the superfluous shoots, so that the See also:winter pruning, in horizontal training, is little more than adjusting the leading shoots and thinning out the spurs, which should be kept See also: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 See also:vertical See also:stem and See also:branch, and trained in afresh, or they may be grafted with other sorts, if a variety of kinds is wanted. Summer and autumn pears should he gathered before they are fully ripe, otherwise they will not in See also:general keep more than a few days. The Jargonelle should be allowed to remain on the tree and be pulled daily as wanted, the fruit from See also:standard trees thus succeeding the produce of the wall trees. In the case of the Crassane the See also:crop should be gathered at three different times, the first a fortnight or more before it is ripe, the second a See also:week or ten days after that, and the third when fully ripe. The first gathering will come into eating latest, and thus the See also: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 See also:short time in a mature See also:state. Diseases.—The pear is subject to several diseases caused by See also:fungi. Gymnosporangium sabinae, one of the rusts (Uredineae) passes one See also:stage ofits See also:life-See also:history on living pear leaves, forming large raised spots or patches which are at first yellow but soon become red and are visible on both faces; on the See also:lower See also:face of each patch is a See also:group of cluster-cups or aecidia containing spores which See also:escape when ripe. This stage in the life-history was formerly regarded as a distinct fungus with the name Roeslelia cancellata; it is now known, however, that the spores germinate on young See also:juniper leaves, in which they give rise to this other stage in the plant's history known as Gymnosporangium.

The gelatinous, generally reddish-See also:

brown masses of spores—the teleutospores—formed on the juniper in the See also:spring germinate and form See also:minute spores—sporidia—which give rise to the aecidium stage on the pear. Diseased pear leaves should be picked off and destroyed before the spores are scattered and the various species of juniper on which the alternate stage is See also:developed should not be allowed near the pear trees. Pear scab is caused by a parasitic fungus, Fusicladium pyrinum, very closely allied and perhaps merely a form of the apple scab fungus, F. dendriticum. As in .e the case of the apple disease it forms large irregular blackish blotches on the fruit and leaves, the injury being often very severe especially in a cool, damp season. The fungus mycelium grows between the cuticle and the epidermis, the former being ultimately ruptured by numerous short branches bearing spores (See also:con- idia) by means of which the disease is spread. As a pre- ventive repeated spraying with dilute See also:Bordeaux mixture is recommended, during the flowering season and See also:early development of the fruit. Similar spraying is recom- (From a specimen in the See also:British Museum.) mended for pear-leaf See also:blister Pear Scab (Fusicladium pyrinum). caused by Taphrina See also:bull¢ta, 1, Leaf showing diseased areas. which forms swollen areas on the 2, See also:Section of leaf surface showing the also b leaves. e attacked yeas may spores or conidia, c, See also:borne on See also:long variety be at See also:insect es a Thus stalks (conidiophores). the younger branches es are Thus the bre often injured by the See also:pearl See also:oyster See also:scale (Aspidiotus ostreaeformis), whichmay be removed by washing in winter with soft See also:soap and hot See also:water. A number of larvae of See also:Lepidoptera feed on the leaves—the remedy is to See also:capture the mature See also:insects when possible. The winter See also:moth (Cheimatobia brumata) must be kept in check by putting greasy bands See also:round the trunks from See also:October till See also:December or See also:January, to catch the wingless See also:females that crawl up and deposit their eggs in the cracks and crevices in the bark. The caterpillars of the See also:leopard moth (Zeuzera pyrina) and of the See also:goat moth (Cossus ligniperda) sometimes See also:bore their way into the trunks and destroy the See also:sap channels. If badly bored, the trees are useless; but in Pear-leaf Cluster-cups (Gymnosporangium sabinae). 1.

Leaf showing See also:

groups of cups or aecidia. 2, Early stage of disease. 3, Cups. the early stages if the entrance of the caterpillars has been detected, a See also:wire should be pushed into the hole. One. of the worst pests of pear trees is the pear midge, known as Diplosis pyrivora or Cecidomyia See also:nigra, the females of which See also:lay their eggs in the flower-buds before they open. The yellow maggots devour the seeds and thus ruin the crop. When deformed fruits are noticed they should be picked off and burned immediately. Species of See also:aphides may be removed by See also:tobacco infusion, soapsuds or other solutions. A See also:gall See also:mite (Phytoptus pyri) sometimes severely injures the leaves, on which it forms blisters—the best remedy is to cut off and See also:burn the diseased leaves. The See also:Alligator or Avocado Pear is Persea gratissima, a member of the natural order Lauraceae, and a native of the See also:West Indies and other parts of tropical See also:America. It is a tree of 25 to 30 ft. high and bears large pear-shaped fruits, See also:green or deep See also:purple in See also:colour, with a See also:firm yellowish-green marrow-like pulp surrounding a large seed. The pulp is much esteemed in the West Indies and is eaten as a See also:salad, usually with the addition of See also:pepper, See also:salt and See also:vinegar.

The pulp contains much oil, which is used for See also:

lighting and soap-making, and the seeds yield a deep indelible See also:black stain which is used for marking See also:linen. Prickly pear is the popular name for species of See also:Opuntia (see See also:CACTUS). The name wooden pear is applied to the fruits of Xylomeluin (nat. ord. Proteaceae), an Australian genus of trees with very thick, woody, inversely pear-shaped fruits which split into two parts when ripe.

End of Article: PEAR (Pyrus communis)

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