I have often heard amateurs, when admiring some of the large specimens in the nurseries here, express astonishment at their prodigious size, which they attribute to their great age, and good soil. But It must be told, that the system of pruning has as much to do in this matter as the age of the trees, or the soil in which they grow. The oldest of the large trees here cannot number more than twelve years, though there are others much older, not half the size. Often have I seen rose trees full of shoots, nearly all proceeding from the base of the head, owing principally to close pruning. When the knife is applied, whether in autumn or in spring, the greater part must be removed, for there is not room enough for the whole to be developed. Now, it is not the production of a large number of branches I consider injurious: if the tree is in a healthy and vigorous condition, this is natural and advantageous. But why should they not be obtained in such positions that they may be of permanent benefit to the plant - be made to extend its size, and render less thinning necessary? This maybe done. Two years ago, after having pruned a number of large specimens, in which I had observed this error, I watched for the bursting of the buds, with the view of practicing disbudding.

When they had shot forth about half an inch, I took a knife with a sharp point and commenced my search at the heart of the tree. From here I rubbed off, close to the bark, a great number of buds, leaving Only such as. from their position promised to increase the size or improve the contour of the head. If a bud was pushing where there was a gap, such was left: the others were thinned, leaving those which took a lateral and outward course of growth. Proceeding upwards, I cleared the center of the tree pretty freely, leaving only just so many buds as seemed necessary to preserve it from becoming straggling. Towards the top, and circumference, also, the buds, where crowded, or likely to cross each other, were removed. A month after the first looking over, fresh buds had broken, and thus was opened a prospect of more gaps being filled, the outlines of the heads being still improved, and their size extended. They were looked over again and again, and the same plan followed out. The growth was, in consequence, more vigorous than that of the previous year, and the flowers fine. On the fall of the leaf in autumn, the succeeding course of action was apparent.

The trees were pruned as usual, and there was little mind exercised in the operation - little thinning required - no necessity to look at the tree for some minutes before one could determine where to begin; which, in my early attempts, I must confess, I have often done, owing to the interminable interfacings of the shoots. The second and third year the same plan was followed, and the trees are now of handsome form, large and healthy, producing an abundance of good flowers. It should be stated that the first year they were taken in hand, they were watered once a week for two months with liquid

The sole reason for this was, that the soil in which they grew had become impoverished. We apply the plan of disbudding to pillar and weeping roses, at toothers, by robbing out any buds that may appear disadvantageously, situated. In the youngest stage of the tree, the bads left to produce flowers and flowering shoots for the subsequent year, should stand about six inches apart on the mam branches: intermediate buds should be rubbed out. The laterals produced in after stages, may also be disbudded; but masses of flower being the object sought here, the practice should not be too freely resorted to. A few words on summer pruning or thinning seem called for. If disbudding can be carried out, there is no need of summer thinning; but, if it cannot be, then the latter practice may be followed to advantage. So soon as the plants have done flowering look them carefully over, thin out the weak unhealthy shoots, and even some of the stout and healthy ones, where they approach each other too nearly: each shoot should stand free and exposed on every side. It is surprising to see how stout and firm the shoots become, and how the leaves increase in size after summer thinning.

The summer kinds submitted to this treatment usually continue their growth by the elongation of the main shoots, the buds on the axils of the leaves remaining dormant; but, with the autumnals, the buds push forth the entire length of the shoots, and the second flow-ering is complete. The trees are improved in both cases, for the shoots grown at this period will produce the finest (lowers in the subsequent season. - Paul's Rose Garden.

Charcoal is an impure form of carbon, and is manufactured on a large scale for the purposes of the arts. The process of manufacture consists in exposing to heat billets of wood, or other organic matter, under such conditions as either wholly or partially to exclude the air. Charcoal has several properties which render it of value to the cultivator. As a manure, it does not act by furnishing carbon to the vegetation; because it is, in reality, one of the most indestructible substances known, and remains for an indefinite length of time without change. But it is remarkably absorptive of certain gases which it retains within its pores in a state of high condensation. A fragment of freshly burned charcoal condenses as much as ninety times its bulk of ammoniacal gas, and thirty-five times its volume of carbonic acid. As these two gases form the principal organic food of plants, it is obvious that charcoal may have a powerful individual action upon their growth. The experiments of Saussure and others, have shown that plants flourish with great luxuriance when the atmosphere in which they grow contains more than the usual amount of carbonic acid.

Chnrcoal, after having absorbed carbonic acid and ammonia from the air, places plants under favorable conditions for receiving of this organic food. The only difference is, that instead of entering the plant by the leaves, they reach it through the roots, which absorb the ram water containing these gases, washed out from the charcoal. Thus, charcoal, from its absorbtive nature, becomes an indirect means of increasing the supply of carbon and nitrogen to plants. Different kinds of charcoal have varying values in this respect. Experiments made by exposing freshly burned pieces of charcoal to the air, showed their different absorptive powers, by the increase in weight after they had been exposed a week to the atmosphere. The charcoal from fir gained 18 per cent, in weight; that from lignum vitae, 9.6; that from box, 14; from beech, 16-8; from oak, 16.5; and from mahogany, 18. Charcoal also possesses the property of absorbing and retaining the odoriferous and coloring principles of most organic substances. It is, on this account, used for removing the putrefactive taint from foul water, or other putrid substances. When used as a filter for foul water, both the smell and color are removed.

From this deodorising property charcoal is frequently mixed with night-soil, and other decaying manures, which it keeps free from smell, and at the same time aids in preserving, by absorbing the gases which would otherwise escape. A mixture of charcoal and burnt clay is frequently used for this purpose with excellent effect. Charcoal, when employed as a manure, acts, to a small extent, by presenting, in a soluble form, the ashes of the wood from which it was prepared: but this action is only temporary, and of small impor-tance; when compared with its principal point of utility, viz: its power of absorbing from the air the gaseous food of plants: and therefore, of presenting it in a more condensed form, ana in greater quantity. - Professor Playfair, in Morton's Cyclopedia of Agriculture.