Page:Encyclopædia Britannica, Ninth Edition, v. 2.djvu/337

Rh ARBORICULTURE 317 afford an adequate return for the number of years they have stood on the ground. Accordingly, we find that the Governments both of France and England grow this descrip tion of timber largely in national forests. The wood of the oak is applicable to a greater number of uses than that of most other trees. Houses, ships, furniture, and machines may be formed almost entirely of oak, and consequently there is a ready sale for this timber almost everywhere. Hence there is more inducement to plant it in Britain than any other hard-wood tree. It is easily raised from acorns, which ought to be collected from the most vigorous trees. The British oak is a native of most parts of Europe, but not of Asia, Africa, or America. The ASH (Fraxinus excelsior, L.) is in Britain next in value to the oak as a timber-tree. It requires a good deep loam with gravelly subsoil, and a situation naturally sheltered, such as the steep banks of glens, rivers, or lakes ; in cold and wet clay it does not succeed. As the value of the timber depends chiefly on its toughness and elasticity, it is best grown in masses where the soil is good ; the trunk is thus drawn up free from large side-branches. The tree is a native of Central Europe, and is easily propagated from seeds. It throws up strong root shoots. The ash requires much light, but grows rapidly, and its terminal shoots pierce easily through thickets of beech, with which it is often associated. Unmixed ash plantations are seldom satisfac tory, because the foliage does not sufficiently cover the ground; but when mixed with beech it grows well, and attains great height and girth. Coppice shoots yield excellent hop-poles, crates, hoops, whip-handles, &c. The timber is much used for agricultural implements, and by coach-builders and wheelwrights. The supply of this valuable timber is annually becoming more limited on account of the decreasing use of hedgerow trees. Of the ELM there are two species, the common or narrow- leaved elm (Ulmus campestris, L.), and the Wych or broad- leaved elm (Ulmus montana, L.) There are many varieties, such as the Dutch elm and the smooth-leaved or Huntingdon elm, the latter much valued for its timber. The narrow- leaved elm is not very common in Scotland, but in the central districts of England it becomes a handsome tree ; and the timber is used for important purposes in ship building, as well as in the construction of machines and agricultural buildings. The Wych elm is a hardy tree, of rapid growth ; but, unless planted in masses, it seldom produces a straight handsome trunk. It strikes from layers with great facility, and when a branch touches the ground it is sure to take root. Few trees are more difficult to uproot than Ulmus montana, and it is rare to see it thrown over by the wind. It has a wide-spreading head, often sloping to one side, and lashing its neighbours with such force that it is sometimes interdicted in mixed plantations. Its timber is more durable than that of the English elm, or of any of the hybrids. It is much used in agricultural carpentry, in rural machinery, and in household furniture. The Wych elm produces abundance of seeds, which, if sown as soon as they are gathered, often come up the same year ; but the English elm and the hybrids produce seeds spar ingly, and are usually propagated by layers or by grafting on the Wych elm. One remarkable difference between the English and Wych elms may be noticed, viz., that the latter never throws up suckers from its roots ; and it is therefore peculiarly valuable as a stock for the English elm, and for those varieties which do throw up suckers. There are other species and varieties of European elms, and several kinds of American elms, but none are deserving of culture in Britain as timber-trees. The elm is subject to the ravages cf several insects, especially Scolytus destructor. The BEECH (Fagus sylvatica, L.) is one of the largest British trees, particularly on chalky or sandy soils. It is a handsome tree in every stage of its growth, but is more injuri ous to plants under its drip than other trees, so that shade- bearing trees, as holly, yew, and thuja, suffer. Its leaves, however, enrich the soil. In England and America the beech has a remarkable power of holding the ground where the soil is congenial, and the deep shade prevents the growth of other trees. It is often and most usefully mixed with oak and Scotch fir. The timber is not remark able either for strength or durability. It was formerly much used in mill-work and turnery ; but its principal use at present is in the manufacture of chairs, bedsteads, and a variety of minor articles. It is a native of the south of England, and of various parts of the continent of Europe. There are some varieties, particularly the purple and weep ing beech; and there are one or two species natives of North America, but none of them deserve notice as timber- trees. It is propagated by its mast, which is produced plentifully in fine seasons. The HORNBEAM (Carp i nits Betulus,TLi.} is an indigenous, moderate-sized, slow-growing tree, bearing a general resem blance to the beech, though of less value. It coppices well, and along with beech is valued for making hedges, as these trees retain their leaves a great part of the winter. The hornbeam is propagated by its nuts, which are produced in abundance. The wood is used for tool-handles, cog wheels, and screws. Selby (British Forest Trees] recom mends the use of the hornbeam as a nurse-tree. The SWEET CHESTNUT (CWajieavwtyam, Lam.) is a large, long-lived, deciduous tree, of rapid growth while young, and attaining a vast size in South Europe (e.g., the renowned chestnut of Mount Etna). It was early introduced to Eng land, and is one of its most ornamental trees. The timber bears a striking resemblance to that of the oak, which has been mistaken for chestnut; but it may be distinguished by the numerous fine medullary rays. Unlike oak, the wood is more valuable while young than old. When not more than fifty years old it forms durable posts for fences and gates; but at that age it often begins to deteriorate, having ring-shakes and central hollows. In a young state, when the stems are not above 2 inches in diameter at the ground, the chestnut is found to make durable hoops for casks and props for vines ; and of a larger size it makes good hop-poles. It is a native of Asia, North Africa, and North America. In Spain and Italy it is grown for its fruit, in Britain, for ornament. In the south of England in warm seasons it ripens its fruit, from which plants are easily raised. None of the other Continental or American species are cultivated in Britain for their timber. The COMMON SYCAMORE or false plane (Acer Pseudo- Platanus, L.), the plane-tree of Scotland, is a large tree naturalised in Britain, though seldom attaining the height of those already mentioned. It withstands the sea and mountain breezes better than most other timber trees, and is often planted near farm-houses and cottages in exposed localities for the sake of its dense foliage. Its wood is valued in turnery, for cups, bowls, and pattern blocks. It produces abundance of seeds, and is easily raised, but it requires good and tolerably dry soil ; it will not thrive on stiff clays nor on dry sands or chalks. The Norway maple (A. platanoides, L.) is a hardy tree, used as a breakwind in exposed situations on the east coast ; but neither it nor the other species from Europe or America seems to deserve cultivation for the sake of its timber. The sugar maple (A. sacchariniim, L.) forms extensive forests in North America. It has been introduced into Britain for a cen tury, but is rather tender, and requires a dry sheltered situation. It is propagated by imported seeds, and it is doubtful if it can be profitably cultivated in this country. The COMMON BIRCH (Betula alba, L.) is a tree of the second rank, worthy of culture in inferior soils and situa-