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WALNUT (Juglans)

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Originally appearing in Volume V28, Page 288 of the 1911 Encyclopedia Britannica.
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WALNUT (Juglans) , a botanical genus of about ten See also:species (nat. ord. Juglandaceae), natives of the temperate regions of the See also:northern hemisphere, extending into See also:Mexico, the See also:West Indies and tropical See also:South See also:America. They are all trees, usually of large See also:size, with alternate stalked, unequally pinnate leaves, and abounding in an aromatic resinous juice. The scars See also:left by the fallen leaves are unusually large and prominent. The buds are not unlike those of the ash; and it frequently happens that in the axils of the leaves, instead of one, several buds may be formed. The utility of this is seen in seasons when the shoot produced from the first bud is killed by See also:frost; then one of the supplementary buds starts into growth, and thus replaces the injured shoot. The See also:flowers are unisexual and monoecious, the numerous See also:males See also:borne in thick catkins proceeding from the See also:side of last See also:year's shoot. The See also:female flowers are solitary or few in number, and borne on See also:short terminal spikes of the See also:present See also:season's growth. In the male See also:flower the receptacle is " See also:con-See also:crescent " or inseparate from the bract in whose axil it originates. The receptacle is, in consequence, extended more or less See also:horizon-See also:tally so that the flowers appear to be placed on the upper See also:surface of horizontally spreading stalks. The perianth consists of five or six oblong greenish lobes, within which is found a tuft, consisting of a large number of stamens, each of which has a very short filament and an oblong two-lobed anther bursting longitudinally, and surmounted by an oblong See also:lobe, which is the projecting end of the connective. There is usually no trace of ovary in the male flowers, though by exception one may occasionally be formed.

The female flower consists of a See also:

cup-like receptacle, inseparate from the ovary, and bearing at its upper See also:part a bract and two bracteoles. From the margin springs a perianth of four short lobes. The one-celled ovary is immersed within the receptacular See also:tube, and is surmounted by a short See also:style with two short ribbon-like stigmatic branches. The solitary ovule springs erect from the See also:base of the ovarian cavity. The See also:fruit is a See also:kind of drupe, the fleshy husk of which is the dilated receptacular tube, while the two-valved See also:stone represents the two carpels. The solitary See also:seed has no perisperm or albumen, but has two large and curiously crumpled cotyledons concealing the plumule, the leaves of which, even at this See also:early See also:stage, show traces of pinnae. The species best known is J. regia, the See also:common walnut, a native of the mountains of See also:Greece, of See also:Armenia, of See also:Afghanistan and the See also:north-west Himalayas. Traces of the former existence of this or of a very closely allied species are found in the See also:Post-See also:Tertiary deposits of See also:Provence and elsewhere, proving the formermuch wider See also:extension of the species. At the present See also:day the See also:tree is largely cultivated in most temperate countries for the See also:sake of its See also:timber or for its edible nuts. The timber is specially valued for See also:furniture and See also:cabinet See also:work and for gunstocks, the beauty of its markings rendering it desirable for the first-named purpose, while its strength and See also:elasticity See also:fit it for the second. The leaves and husk of the fruit are resinous and astringent, and are sometimes used medicinally as well as for See also:dyeing purposes. A Spiritus Nucis Juglandis is given as an antispasmodic.

It doubtless owes its properties to the See also:

alcohol which it contains. See also:Sugar is also prepared from the See also:sap in a similar manner to that obtained from the See also:maple. The See also:young fruits are used for pick-See also:ling. When ripe the seeds are much esteemed as a delicacy, while in See also:France much oil of See also:fine quality is extracted from them by pressure. There are several varieties in cultivation, varying in the degree of hardihood, See also:time of ripening, thickness of See also:shell, size and other particulars. In the See also:climate of See also:Great See also:Britain a See also:late variety is preferable, as securing the young shoots against injury from frost, to which otherwise they are very subject. The See also:kernel of the large-fruited variety is of very indifferent quality, but its large shells are made use of by the See also:French as trinket cases. The walnut is mentioned in the earliest See also:British botanical writings, and is supposed to have been introduced by the See also:Romans. It grows well, and ripens its fruit in the See also:southern and midland counties of See also:England; but large trees may be seen as far north as See also:Ross-See also:shire in sheltered places. The tree succeeds in deep, sandy or calcareous loarns, and in stiff loarns resting on a gravelly bottom. It requires See also:free exposure to See also:air and See also:light. It is propagated by seeds, and occasionally by budding, grafting or inarchiiig for the perpetuation of See also:special varieties.

Seedlings should be protected from frost during the first See also:

winter. The trees See also:form their heads naturally, and therefore little pruning is required, it being merely necessary to cut off straggling growths, and to prevent the branches from interlacing. The best time for performing this is in the autumn, just after the fall of the See also:leaf. See also:Plants raised from the seed seldom become productive till they are twenty years old. The fruit is produced at the extremities of the shoots of the preceding year; and therefore, in gathering the See also:crop, care should be taken not to injure the young See also:wood. In some parts of England the trees are thrashed with rods or poles to obtain the nuts, but this is not a commendable mode of See also:collecting them. Among the See also:American species J. See also:nigra, the See also:black walnut, is especially noteworthy as a very handsome tree, whose timber is of great value for furniture purposes, but which is now becoming scarce. In Britain it forms a magnificent tree. The See also:white walnut or butternut, J. cinerea, is a smaller tree, though it sometimes reaches See also:loo ft. in height; its inner bark yields an extractive, juglandin, given as an hepatic stimulant and cathartic in doses of 2-5 grains. Closely allied to the walnuts, and sometimes confounded with them, are the hickories.

End of Article: WALNUT (Juglans)

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