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TREE (0. Eng. treo, treow, cf. Dan. t...

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Originally appearing in Volume V27, Page 235 of the 1911 Encyclopedia Britannica.
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TREE (0. Eng. treo, treow, cf. Dan. tree, Swed. Odd, tree, trd, timber; allied forms are found in Russ. drevo, Gr. opus, oak, and 36pv, spear, Welsh derw, Irish darog, oak, and Skr. dare, wood), the term, applied in a wide sense, to all plants which grow with a permanent single woody stem or trunk of some height, branching out at some distance from the ground. There is a somewhat vague dividing line, in popular nomenclature, between " shrubs " and " trees," the former term being usually applied to plants with several stems, of lower height, and bushy in growth. The various species to which the name " tree " can be given are treated under their individual titles, e.g. oak, ash, elm, &c.; the articles FIR and PINE treat of two large groups of conifers; general information is provided by the articles PLANTS and GYMNOSPERMS; tree cultivation will be found under FORESTS AND FORESTRY and HORTICULTURE; and the various types of tree whose wood is useful for practical purposes under TIMBER. Apart from this general meaning of the word, the chief transferred use is that for a piece of wood used for various specific purposes, as a framework, bar, &c., such as the tree of a saddle, axle-tree, cross-tree, &c. TREE-CREEPER, one of the smallest of British birds, and, regard being had to its requirements, one very generally distributed. It is the Certhia familiaris of ornithology, and is remark-able for the stiffened shafts of its long and pointed tail-feathers, aided by which, and by its comparatively large feet, it climbs the trunks or branches of trees, invariably proceeding upwards or outwards and generally in a spiral direction, as it seeks the small insects that are hidden in the bark and form its chief food. When in the course of its search it nears the end of a branch or the top of a trunk, it flits to another, always alighting lower down than the place it has left, and so continues its work. Inconspicuous in colour—for its upper plumage is mostly of various shades of brown mottled with white, buff and tawny, and beneath it is of a silvery white—the tree-creeper is far more common than the incurious suppose; but, attention once drawn to it, it can be frequently seen and at times heard, for though a shy singer its song is loud and sweet. The nest is neat, generally placed in a chink formed by a half-detached piece of bark, which secures it from observation, and a considerable mass of material is commonly used to stuff up the opening and give a sure foundation for the tiny cup, in which are laid from six to nine eggs of a translucent white, spotted or blotched with rust-colour. The tree-creeper inhabits almost the whole of Europe as well as Algeria and has been traced across Asia to Japan. It is now recognized as an inhabitant of the greater part of North America, though for a time examples from that part of the world, which differed slightly in the tinge of the plumage, were accounted a distinct species (C. americana) and even those from Mexico and Guatemala (C. mexicana) have lately been referred to the same. It therefore occupies an area not exceeded in extent by that of many passerine birds and is one of the strongest witnesses to the close alliance of the so-called Nearctic and Palaearctic regions. Allied to the tree-creeper, but without its lengthened and stiff tail-feathers, is the genus Tichodroma, the single member of which is the wall-creeper (T. muraria) of the Alps and some other mountainous parts of Europe and Asia. It is occasionally seen in Switzerland, fluttering like a big butterfly against the face of a rock conspicuous from the scarlet-crimson of its wing-coverts and its white spotted primaries. Its bright hue is hardly visible when the bird is at rest, and it then presentsadingy appearance of grey and black. It is a species of wide range, extending from Spain to China; and, though but seldom leaving its cliffs, it has wandered even so far as England. Merrett (Pinax, p. 177) in 1667 included it as a British bird, and the correspondence between Marsham and Gilbert White (Prot. Norf. and North. Nat. Society, ii. 18o) proves that an example was shot in Norfolk, on the 3oth of October 1792; while another is reported (Zoologist, and series, p. 4839) to have been killed in Lancashire on the 8th of May 1872. The passerine family Certhiidae contains a number of genera of birds to which the general name "creeper" is applied; they occur in North America, Europe and Asia, the greater part of Africa, and Australia and New Guinea. (A. N.) TREE-FERN. In old and well-grown specimens of some of the familiar ferns of temperate climates the wide-spreading crown of fronds may be observed to rise at a distance often of a good many inches above the ground, and from a stem of consider-able thickness. The common male fern Lastraea (Filix-mas) affords the commonest instance of this; higher and thicker trunks are, however, occasionally presented by the royal fern (Osmunda regalis), in which a height of 2 ft. may be attained, and this with very considerable apparent thickness, due, however, to the origin and descent of a new series of adventitious roots from the bases of each annual set of fronds. Some tropical members and allies of these genera become more 'distinctly tree-like, e.g. Todea; Pterir also has some sub-arboreal forms. Oleandra is branched and shrub-like, while Angiopteris and Maratlia may also rise to 2 ft. or more. But the tree-ferns proper are practically included within the family Cyatheaceae. This includes seven genera (Cyathea, Alsophila, Hemitelia, Dicksonia, Thyrsopteris, Cibotium and Balantium) and nearly 300 species, of which a few are herbaceous, but the majority arboreal and palm-like, reaching frequently a height of 5o ft. or more, Alsophila excelsa of Norfolk Island having sometimes measured 6o to 8o ft. The fronds are rarely simple or simply pinnate, but usually tripinnate or decompound, and may attain a length of 20 ft.,thus forming a splendid crown of foliage. The stem may occasionally branch into many crowns. The genera are of wide geographical range, mostly within the tropics; but South Australia, New Zealand, and the southern Pacific islands all possess their tree-ferns. In Tasmania Alsophila australis has been found up to the snow-level, and in the humid and mountainous regions of the tropics tree-ferns are also found to range up to a considerable altitude. The fronds may either contribute to the apparent thickness of the stem by leaving more or less of-their bases, which become hardened and persistent, or they may be articulated to the stem and fall off, leaving characteristic scars in spiral series upon the stem. The stem is frequently much increased in apparent thickness by the downgrowth of aerial roots, forming a black coating several inches or even a foot in thickness, tut its essential structure differs little in principle from that familiar in the rhizome of the common bracken (Pteris). To the ring or rather netted cylinder of fibrovascular bundles characteristic of all fernstems scattered internal as well as external bundles arising from these are superadded and in a tree-fern the outer bundles give off branches to the descending roots from the region where they pass into the leaves. Tree-ferns are cultivated for their beauty alone; a few, however, are of some economic applications, chiefly as sources of starch. Thus the beautiful Alsophila excelsa of Norfolk Island is said to be threatened with extinction for the sake of its sago-like pith, which is greedily eaten by hogs; Cyathea medullaris also furnishes a kind of sago to the natives of New Zealand, Queensland and the Pacific islands. A Javanese species of Dicksonia (D. chrysotricha) furnishes silky hairs, which have been imported as a styptic, and the long silky or rather woolly hairs, so abundant on the stem and frond-leaves in the various species of Cibotium have not only been put to a similar use, but in the Sandwich Islands furnish wool for stuffing mattresses and cushions, which was formerly an article of export. The " Tartarian lamb," or Agnus scythicus of old travellers' tales in China and Tartary, is simply the woolly stock of Cibotium Barometz, which, when dried and inverted, with all save four of its frond-stalks cut away, has a droll resemblance to a toy sheep.
End of Article: TREE (0. Eng. treo, treow, cf. Dan. tree, Swed. Odd, tree, trd, timber; allied forms are found in Russ. drevo, Gr. opus, oak, and 36pv, spear, Welsh derw, Irish darog, oak, and Skr. dare, wood)
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THOMAS TREDGOLD (1788-1829)
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TREE FROG

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