When a tree is supplied by numerous, consequently small and not wide-extending roots, as the tree acquires size, the wide spreading branches and leafy top shed off the rain and dews from the space occupied by these roots, very few of them extending beyond this shade; at the same time, this narrow space becomes soon exhausted of the more particular pabulum necessary to the kind of plant, the exhaustion being accelerated by the dryness. This dryness and exhaustion of the soil very soon show their effects aloft; the living hark of the tree becomes covered from its connexion with the air, and constricted by a thick hard dead crust, which, with the consequent very thin alburnum affording an inefficient communication between the supply and demand, react to impair the general vigour, and particularly to impede the descent of the proper sap necessary to the enlargement and further extension of the roots. The buds {113} not receiving sufficient supply of root-moisture, instead of pressing on to new formation of wood, only find enough to burgeon out into flower-buds, which the following season drain the tree by reproduction; this fruit-bearing alternates with periods of exhaustion, when the buds have not even supply sufficient to swell into the embryo of flower and seed, but extend only into a few leaves; and sometimes, in the event of a benign season, the buds may throw out a small extension of new shoots. The tree progresses very slowly in thickness of bole all this time, and generally soon falls a prey to disease. On the other hand, when the tree has its naturally fine large roots preserved, and is situated in open forest, and mixed with other kinds, these large roots diverging widely from the tree and each other, have a much larger less-sought space to forage in; and the tree enjoying a long period of luxuriant growth before it fall much into seed-bearing, acquires strength of constitution to thrive and increase for ages under this drain. We are satisfied that cutting or fracture of the root-leaders, especially near the bulb, when they have acquired some size, is injurious to the extension and longevity of the tree, in pines and most kinds of hard wood; and that branch-pruning, as generally practised, is not less pernicious, first, by the {114} derangement which the plant receives, from the regular connexion between the rootlets and their affiliated twigs and leaves being destroyed by the section, and afterwards from the distance between the manufacturing parts, the leaves and the sources of supply in the ground being unnaturally extended, especially when the stem is long, slender, and much denuded.