Page:Encyclopædia Britannica, Ninth Edition, v. 17.djvu/749

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OAK 691 ing became common. At present large quantities of timber are still obtained from hedgerows and copsewoods ; but, although some attempts have been made to renew the royal forests, much of the oak timber employed in Britain is im ported from abroad. Many of the Continental woods are failing to produce their former supply ; the large quantity still obtained from the port of Memel, and formerly drawn from Prussia and nearer Poland, is now brought thither from the distant forests of the Dnieper and the Don. The wood of the British oak, when grown in perfection, is the most valuable produced in temperate climates. The heart -wood varies in colour from dark brown to pale yellowish -brown ; hard, close-grained, and little liable to split accidentally, it is, for a hard wood, easy to work. Under water it excels most woods in durability, and none stand better alternate exposure to drought and moisture, while under cover it is nearly indestructible as long as dry-rot is prevented by free admission of air. Its weight varies from 48 to about 55 lb the cubic foot, but in very hard slowly-grown trunks sometimes approaches 60 ft. The sap-wood is lighter and much more perishable, but is of value for many purposes of rural economy. The relative FIG. 3. Q. sessiliflora ; half natural size. (From Kotschy, op. cit., plate xxxii.) qualities of the two varieties have been the frequent sub ject of debate, the balance of practical testimony seeming to establish the superiority of Q. pedunculatci as far as durability in water is concerned ; but when grown under favourable circumstances the sessile oak is certainly equally lasting if kept dry. The wood of the durmast oak is commonly heavier and of a darker colour, hence the other is sometimes called by woodmen the white oak, and in France is known as the "chcae blanc." The oak of Britain is still in great demand for the construction of merchant shipping, though teak has become in some measure its substitute, and foreign oak of various quality and origin largely takes its place. Its great abundance of curved trunks and boughs rendered the oak peculiarly valuable to the shipwright when the process of bending timber artificially was less understood ; the curved pieces are still useful for knees. The younger oaks are employed by the carpenter, wheelwright, waggon -builder, and for innumerable purposes by the country artisan. The most durable of fences are those formed of small oaks, split lengthwise by the wedge into thin boards. The finely- grained heart-wood is sought by the cabinetmaker for the manufacture of furniture, and high prices are often given for the gnarled and knotted portions of slowly-grown trees, to be sawn into veneers. Oak Avas formerly largely used by wood -carvers, and is still in some demand for those artists, being harder and more durable than lime and other Avoods that yield more readily to the sculptor s tool. Oak was thus applied at a very early date; the shrine of Edward the Confessor, still existing in the abbey at West minster, sound after the lapse of 800 years, is of dark- coloured oak-wood. The wood, of unknown age, found submerged in peat-bogs, and of a black hue, is largely used in decorative art under the name of " bog-oak." The oak grows most luxuriantly on deep strong clays, calcareous marl, or stiff loam, but will flourish in nearly any deep well-drained soil, excepting peat or loose sand ; in marshy or moist places the tree may grow well for a time, but the timber is rarely sound; on hard rocky ground and exposed hillsides the growth is extremely slow and the trees small, but the wood is generally very hard and durable. The oak will not bear exposure to the full force of the sea gale, though in ravines and on sheltered slopes oak woods sometimes extend nearly to the shore. The cultivation of this tree in Europe forms one of the most important branches of the forester s art. It is fre quently raised at once by sowing the acorns on the ground where the trees are required, the fruit being gathered in the autumn as soon as shed, and perfectly ripe seeds selected ; but the risk of destruction by mice and other vermin is so great that transplanting from a nursery-bed is in most cases to be preferred. The acorns should be sown in November on well-prepared ground, and covered to a depth of 1| or 2 inches; the seeds germinate in the spring, and the seedlings are usually transplanted when one or two years old to nursery -beds, where they are allowed to grow from two to four years, till required for the plantation. Some authorities recommend the tap-roots to be cut in the second year, with the view of increasing the ball of fibre ; but, if the trees are removed from the seed bed sufficiently early, the root is best left to its natural development. The oak requires shelter in the early stages of growth ; in England the Scotch pine is thought best for this purpose, though Norway spruce answers as well on suitable ground, and larch and other trees are sometimes substituted. The conifers are allowed to grow to a height of from 3 to 5 feet before the young oaks are planted, and are gradually thinned out as the latter increase in size. The distance between the oaks depends upon the growth intended before thinning the young wood ; usually they are placed from 8 to 12 feet apart, and the superabundant trees cut out as they begin to interfere with each other. The lower branches often require removal, to ensure the formation of a tall straight trunk, and this operation should be performed before the superfluous shoots get too large, or the timber will be injured ; but, as with all trees, un necessary pruning should be avoided, as every branch removed lessens the vigour of growth. Where artificial copsewood is the object, hazel, hornbeam, and other bushes may be planted between the oaks ; but, when large timber is required, the trees are best without undergrowth. The oak, after the trunk is felled, throws up shoots from the cut stump more surely and abundantly than most trees ; hence it is well adapted for the formation of brush wood, of which" great quantities are employed in Britain for the manufacture of crates and hoops, and for many other uses. Where the underwood consists mainly of oak it is generally cut once in twenty years, but in some places fifteen years are thought sufficient, while on poor land thirty years are sometimes allowed to intervene between the cuttings. Oak coppices are generally cut in the spring, because the bark is then more readily separated, and large timber trees are very often felled at the same period ; but winter felling is probably best when sound heart-wood is the chief thing in view. The growth of the oak is slow, though it varies greatly in different trees ; Loudon states that an oak, raised from the acorn in a garden at Sheffield Place, Sussex, became in seventy years 12 feet in circum-