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YEW (Taxus baccata)

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Originally appearing in Volume V28, Page 919 of the 1911 Encyclopedia Britannica.
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YEW (Taxus baccata), a tree which belongs to a genus of Coniferae (see GYMNOSPERMS), in which the ordinarily woody Yew. 1, shoot with male flowers; 2, leaf and in section; 3, branch bearing two ripe seeds each with its crimson aril; 4, male flowers; 5, stamens; 6, 7, female flower in different stages; 8, section of ripe seed and aril, a. 1, slightly reduced ; 2, and 4 to 8, enlarged. cone is represented by a single seed surrounded by a fleshy cup. Usually it forms a low-growing evergreen tree of very a 8 diverse habit, but generally with dense spreading branches, thickly covered with very dark green linear leaves, which are given off from all sides of the branch, but which, owing to a twist in the base of the leaf, become arranged in a single series on each side of it. The trees are usually dioecious, the male flowers being borne on one individual and the female on another, although instances occur in which flowers of both sexes are formed on the same tree. The male flowers are more or less globular and occur in the axils of the leaves. They consist of a number of overlapping brownish scales, gradually increasing in size from below upwards and surrounding a naked stalk that bears at its summit a head of four to eight stamens. Each stamen has a flat five-lobed top, something like a shield; from its under surface, five, six or more pollen cases hang down, and these open lengthwise to liberate the globose pollen-grains. The female flowers are also placed each separately in the axil of a leaf, and consist of a number of overlapping scales, as in the male. These scales surround a cup which is at first shallow, green and thin (the so-called aril), but which subsequently becomes fleshy and red, while it increases so much in length as almost entirely to conceal the single straight seed. It is clear that the structure of the female flower differs from that of most conifers, from which it is now often separated in a distinct order, Taxacea.e. The poisonous properties, referred to by classical writers such as Caesar, Virgil and Livy, reside chiefly if not entirely in the foliage. This, if eaten by horses or cattle, especially when it has been cut and thrown in heaps so as to undergo a process of fermentation, is very injurious. The leaves have also been used for various medicinal purposes, but are not employed now. An alkaloid taxine, said to depress the circulation, is extracted. It forms white crystals soluble in alcohol and ether. As a timber tree the yew is used for cabinet-work, axle-trees, bows and the like, where strength and durability are required. The yew occurs wild over a large area of the northern hernisphere. In N.E. America and in Japan trees are found of a character so similar that by some botanists they are all ranged under one species. Generally, however, the European yew, T. baccata, is regarded as native of Europe, N. Africa, and Asia as far as the Himalayas and the Amur region, while the American and Japanese forms are considered to represent distinct species. The yew is wild in Great Britain, forming a characteristic feature of the chalk downs of the southern counties and of the vegetation of parts of the Lake District and elsewhere. The evidence of fossil remains, antiquities and place-names indicates that it was formerly more widely spread in Europe than at the present day. The varieties grown in the United Kingdom are numerous, one of the most striking being that known as the Irish yew—a shrub with the pyramidal or columnar habit of a cypress, in which the leaves spread from all sides of the branches, not being twisted, as they usually are, out of their original position. In the ordinary yew the main branches spread more or less horizontally, and the leaves are so arranged as to be conveniently exposed to the influence of the light; but in the variety in question the branches are mostly vertical, and the leaves assume a direction in accordance with the ascending direction of the branches. The plants have all sprung from one of two trees found growing wild more than a hundred years ago on the mountains of Co. Fermanagh in Ireland, and afterwards planted in the garden of Florence Court, a seat of the earl of Enniskillen. The yew is a favourite evergreen tree, either for planting separately or for hedges, for which its dense foliage renders it well suited. Its dense growth when pruned has led to its extensive use in topiary work, which was introduced by John Evelyn and became very prevalent at the close of the 17th and the beginning of the 18th centuries. The wood is very hard, close-grained and of a deep red-brown colour internally. The planting of the yew in churchyards was at one time supposed to have been done with a view to the supply of yew staves. But, while importation from abroad was fostered, there seems to have been no statute enforcing the cultivation of the yew in Great Britain; a statute, however, of Edward I. (cited in The Gardeners' Chronicle, 6th March 1880, p. 306) states that the trees were often planted in churchyards to defend the church from919 high winds. The Crowhurst yew, mentioned by Evelyn as 30 ft. in circumference, still exists. The large yew at Ankerwyke, near Staines, with a trunk 304 ft. in circumference, in sight of which Magna Carta was signed (1215), probably exceeds a thousand years of age. The fine yew in Buckland churchyard, near Dover, was removed in 188o to a distance of 6o yds. The trunk had been split so that it had a direction nearly parallel with the soil. This huge tree was moved with a ball of soil round its roots, 16 ft. 5 in. by 15 ft. 8 in., by 3 ft. 62 in. in depth, the weight of the entire mass being estimated at 56 tons. The dimensions of the tree in 188o were as follows: " circumference of the main trunk, 22 ft.; of the upright portion of the trunk, 6 ft. so in.; second horizontal trunk, 10 ft. 10 in.; do., south limb forking off at 9 ft. from the main trunk, 7 ft. to in.; do., west limb forking off at 9 ft. from the main trunk, 8 ft. 8 in.; extent of branches from centre of main trunk southwards, 30 ft. io in., and from north to south, 48 ft.; they extend from the main trunk. westward 33 ft." The tree was replanted so that the horizontal portions were replaced in their original erect position and the natural symmetry restored. For further details see Veitch, Manual of Coniferae (1900); Elwes and Henry, Trees of Great Britain and Ireland (1906).
End of Article: YEW (Taxus baccata)
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