In order to the full success of this operation, grafting must be performed according to the rules that experience has laid down. The first is to graft or unite only such species as have a relationship subsisting between them. The operation never succeeds unless this union of nature is attended to, and the plants belong to the same genus. The next rule requires that the inner bark of the scion, and the inner bark of the stalk, be exactly united together, in order to facilitate the free course of the sap.
The most common method of grafting is whip-grafting, or tongue-grafting. The name of whip-grafting is given from the method of cutting the stock and the scion sloping on one side so as to fit each other, and then tying them together in the manner of a whip-thong to the shaft or handle. The scion and stock are cut obliquely, and as nearly as possible at corresponding angles. The top of the stock is then cut off nearly horizontally, and a slit is made near the centre of it downwards, and a similar one in the scion upwards. The tongue, or wedge-like process forming the upper part of the sloping face of the scion, is then inserted downwards in the cleft of the stock, the inner barks being brought closely to unite on one side so as not to be displaced by tying, which ought to be done immediately with a riband, or matting, or bass, brought in a neat manner several times round the stock. The next operation is to clay the whole over an inch thick all round, for about half an inch or more below the bottom of the graft to an inch over the top of the stock, finishing the coat of clay in a kind of oval form, closing it effectually, so that no light, wet, nor wind, may penetrate.
TONGUE-GRAFTING.
Tongue-grafting is not very different to whip-grafting, and is performed as follows. The stock being ready, cut it off at three or four inches from the ground, and, with a very sharp, straight, and narrow-bladed knife, cut a thin slip of wood and bark upwards from about two inches below the top of the shortened stock. Make this cut at one pull of the knife, inserting the edge rather horizontally, and when it has gone through the bark and into the wood a little short of the middle, pull straight upwards. Then at less than half-way down this cut a thin tongue, not more than three-eighths of an inch long. Proceed in the same way with the thick part of the scion, making a sloping cut of about the same length as the cut of the stock, and make a tongue to correspond with that in the stock. Bring the four edges of the bark, that is, the two edges of the cut in the top of the stock and the two corresponding edges of the cut in the bottom of the scion, to meet precisely, which can never be the case unless the first cut in the stock and that in the scion is even as a die, and performed with a knife as sharp as a razor. The two parts thus formed, the tongues and the stock clasping one another must be bound up as before.
BUDDING.
Budding is the art of taking a bud from one tree and making it grow on another. A bud can only be planted upon a tree of the same kind as itself, and the operation is generally performed in the month of August. The bud should be taken from a shoot of the same year’s growth, and, in taking it, should be neatly cut out by incisions made above it, below it, and longitudinally on either side, and the piece taken should include the bud, without injury to the bark, and a small piece of wood of an oblong form pointed at its extremity. A place is now cut to receive the bud in the shoot of a stock, and the best place is near the fork of a branch; the method of cutting is similar to that adopted for taking out the bud, and the bark is open on both sides of the slit, and the piece of bark to which the bud is attached is then filled in, and the bark of the stock closed over it; the two parts are then bound together with strips of fresh matting tied in bows and ends, for the purpose of being easily loosened as the bud increases in growth. The operation of budding requires the aid of a budding-knife, which may be readily purchased, and the success of the operation depends upon the care and nicety with which it is performed.
INARCHING.
We have already mentioned how nature performs what is called inarching. The gardener’s art consists simply in bending a branch partly cut through, and inserting the belt thus formed into a slit made downwards in the stock to receive it. The parts being nicely fitted are bound with matting. In five or six months the head of the stock may be cut off, and the plant removed.