ARBORICULTURE. 



bear foliage and fruit, affords indubitable proof of 

 a very remarkable circumstance connected with 

 the vegetable kingdom. In man and all other 

 animals, we find an organisation and a process 

 of life going on, which are destined to cease at 

 a certain period. But it is otherwise with trees. 

 They appear to possess the power of growing 

 on for ever without exhibiting any symptoms 

 of decay, unless from accidental or extraneous 

 causes. ' As there is formed every year a lig- 

 neous deposit, and generally new organs, there is 

 not among the vegetable creation place for that 

 hardness or rigidity, that obstruction of old and 

 permanent organs, which constitute properly the 

 death from age, and, consequently, that being the 

 case, trees can only die from accidental causes. 

 Trees do not die from age, in the true sense of 

 the word : they have no fixed period of existence ; 

 and, consequently, some may be found that have 

 arrived at an extraordinary age.' But although 

 a tree thus possesses in itself the elements of 

 continual strength and youth, numerous causes 

 step in to interrupt or destroy its existence ; so 

 that we are not to be surprised if the number of 

 such vegetable patriarchs should prove exceedingly 

 small, compared with the immense extent of the 

 earth's surface which is covered with forest- 

 growth. 



CLASSIFICATION OF TREES. 



In arboriculture, trees are sometimes classified 

 according to their uses ; for example i. Trees 

 which produce straight timber for masts and long 

 planks as the various tribes of pines. 2. Trees 

 which afford crooked timber for knees or bends 

 in the ribs of ships, &c. as the oak, sweet chest- 

 nut, broad-leaved elm, &c. 3. Trees which give 

 tough pieces of timber as the yew, holly, thorn, 

 ash, hickory, maple, &c. 4. Hard-wood trees 

 as the oak, beech, plane, walnut, and box. 

 5. Soft-wood trees as the poplar, large willow, 

 lime, horse-chestnut, &c. 6. Wood or spray grown 

 for hoops, baskets, besoms, poles, &c. as the 

 dwarf willows and birch. To these may be added 

 woods of foreign growth as rose-wood, satin- 

 wood, and mahogany, which are employed for 

 ornamental purposes. 



According to another classification, trees are 

 arranged as of three kinds coniferous or resinous, 

 hard-wooded, and soft-wooded. For the sake of 

 clearness, we will adopt this simple arrangement, 

 confining ourselves to a few of the more important 

 trees which may be grown in the climate of 

 Britain. 



i. Coniferous Trees. 



The obvious distinction of these trees is the 

 production of cones containing their seeds ; but 

 they present other peculiarities. Their stems are 

 usually tall and straight, bearing symmetrically 

 arranged side-branches ; and the wood-cells or 

 wood-tubes of which their timber is composed, 

 exhibit under the microscope peculiar discs with 

 a central dot as shewn in the accompanying 

 figure which at all times serve to distinguish 

 coniferous timber from that of other families of 

 plants, whether fossil or recent, even in a charred 

 state. 



The Coniferas are not only useful timber-trees, 

 but are also highly ornamental, their lofty trunks 



and pendent branches, clothed with peculiar ever- 

 green foliage, rendering them conspicuous and 

 pleasing objects -in the landscape, either when 



Coniferous Tissue of Wellingtons gigantat 

 (260 diameters). 



grown singly or in groups or plantations. On 

 this account, the Coniferae have of late years 

 received much attention from those interested in 

 the improvement of estates ; while the constant 

 succession of new and useful additions that have 

 recently been made to the lists of species suitable 

 for our climate, has served to heighten the interest 

 of this family of trees. 



Scotch Pine or Scots Fir (Pinus sylvestris). 

 This is a tall and generally straight tree, with few 

 branches on the lower part of the stem, the foliage 

 being confined to the top of the plant, and there 

 forming a massive clump. The numerous uses 

 to which pine-timber is applied in this and other 

 countries are well known. The Scotch pine is 

 indigenous to the northern parts of Europe and 

 Western Asia, and forms vast natural forests in 

 the Highlands of Scotland. It grows in almost 

 any soil, provided there be not a superabundance 

 of moisture, and is justly valued as one of pur 

 most useful timber-trees. The two leading 

 varieties are i. The red-wooded or native ; and 

 2. The white-wood, Haguenau, or continental 

 Scots fir. Both are extensively grown ; but a 

 preference is usually given to the native sort, and 

 especially to young trees grown from seeds saved 

 in the indigenous forests of Scotland. ' The tree 

 assumes its most picturesque form when standing 

 singly, with room to spread out its branches. 

 When grown close together, the trees are found 

 clean-stemmed, and drawn up to a great height ; 

 consequently, such trees are available for many 

 purposes ; whereas, when standing singly, the tree 

 is generally short-stemmed, thick, and branchy. 

 No tree, a native of Britain, can with more safety 

 be planted out into any soil and situation, pro- 

 vided only that soil be a dry one.' 



Weymouth Pine (Pinus Strobus\Tte Wey- 

 mouth pine produces a whitish-yellow wood, which 

 is pretty hard, fine-grained, and easily worked; 

 and being usually straight, this timber is much used 

 for masts, bowsprits, &c. It was introduced into 

 this country about the beginning of the eighteenth 

 century, from America. Lord Weymouth was 

 the first proprietor who planted this tree exten- 

 sively in Britain. It accommodates itself to most 

 kinds of soils, but attains greatest perfection in 

 valleys and on river-banks, where there is an 

 accumulation of vegetable matter ; so situated, it 



