PROPAGATION.—SECTION III.—BUDDING.
ADVANTAGES OF—LONG PERIOD FOR—CLAIMS OF GREATER HARDINESS EXAMINED—LATE GROWERS APT TO BURST THE BARK—BUD TENDER SORTS. STOCKS NOT ALWAYS HARDY—PHILOSOPHY OF BUDDING, LIKE GRAFTING, DEPENDS UPON CELL-GROWTH—THE CAMBIUM, OR "PULP"—THE BUD, ITS INDIVIDUALITY—THOMSON QUOTED—UNION DEPENDS UPON THE BUD—SEASON FOR BUDDING—CONDITIONS REQUISITE—SPRING BUDDING—CONDITION OF THE BUDS—BUD STICKS—SELECTION OF—THEIR TREATMENT—RESTORATION WHEN DRY—THE WEATHER—RAINS TO BE AVOIDED—USUAL PERIOD OF GROWTH BY EXTENSION—SUCCESSION OF VARIETIES—CHERRY, PLUM, PEAR, APPLE, QUINCE, PEACH—HOW TO DO IT—DIFFERENT METHODS—AGE OF STOCKS—PREPARATION OF—THE KNIFE—CUTTING THE BUDS—REMOVAL OF THE WOOD—THE AMERICAN METHOD—DIVISION OF LABOR TYING—RING BUDDING—PREPARATION OF SCIONS FOR EARLY BUDDING—IMPROVEMENTS IN TYING—BAST, PREPARATION OF—SUBSTITUTES—NOVEL TIE—WHEN TO LOOSEN THE BANDAGE—HOW DONE—INSPECTION OF BUDS—SIGN OF THEIR HAVING UNITED—KNIGHT'S TWO BANDAGES—WHY LEAVE THE UPPER ONE LONGER. HEADING BACK THE STOCKS—RESUME.
Budding, or inoculating, is the insertion of eyes or buds. This is a favorite method of propagation, which is practiced in the multiplication of a great variety of fruits. The advantages of budding consist in the rapidity and facility with which it is performed, and the certainty of success which attends it. Budding may be done during a long period of the growing season, upon the different kinds of trees we have to propagate. Using but a single eye, it is also economical of the scions, which is a matter of some importance, when we desire to multiply a new and scarce variety.
It has been claimed on behalf of the process of budding, that trees, which have been worked in this method, are more hardy and better able to resist the severity of winter than others of the same varieties, which have been grafted in the root or collar, and also that budded trees come sooner into bearing. Their general hardiness will probably not be at all affected by their manner of propagation; except perhaps, where there may happen to be a marked difference in the habit of the stock, such for instance as maturity early in the season, which would have a tendency to check the late growth of the scion placed upon it—the supplies of sap being diminished, instead of continuing to flow into the graft, as it would do from the roots of the cutting or root-graft of a variety which was inclined to make a late autumnal growth. Practically, however, this does not have much weight, nor can we know, in a lot of seedling stocks, which will be the late feeders, and which will go into an early summer rest.
Certain varieties of our cultivated fruits are found to have a remarkable tendency to make an extended and very thrifty growth, which, continuing late into the autumn, would appear to expose the young trees to a very severe trial upon the access of the first cold weather, and we often find them very seriously injured under such circumstances; the bark is frequently split and ruptured for several inches near the ground. The twigs, still covered with abundant foliage, are so affected by the frost, that their whole outer surface is shriveled, and the inner bark and wood are browned; the latter often becomes permanently blackened, and remains as dead matter in the centre of the tree, for death does not necessarily ensue. Now intelligent nurserymen have endeavored to avoid losses from these causes, by budding such varieties upon strong well-established stocks, though they are aware that these are not more hardy than some of the cultivated varieties: a given number of seedling stocks has been found to suffer as much from the severity of winter, as do a similar amount of the grafted varieties taken at random.[15] That the serious difficulty of bark-bursting occurs near the surface of the ground, does seem to be an argument of some weight in favor of budding or stock-grafting at a higher point. The earlier fruiting of budded trees than those which have been root-grafted, does not appear to be a well established fact, and therefore need not detain us; except to observe that the stocks, upon which the buds were inserted, might have been older by some years than the slip of root upon which the graft was set, so that the fruiting of the former tree should count two or three or more years further back than from the period of the budding. There are so many causes which might have contributed toward this result of earlier bearing, that we should not be too hasty in drawing conclusions in this matter.
The philosophy of budding is very similar to that of grafting. The latter process is performed when the plant-life is almost dormant, and the co-apted parts are ready to take the initiative steps of vegetation, and to effect their union by means of new adventitious cells, before the free flow of sap in the growing season. Budding, on the contrary, is done in the hight of that season and toward its close, when the plants are full of well matured and highly organized sap, when the cell circulation is most active, and the union between the parts is much more immediate than in the graft; were it not so, indeed, the little shield, with its actively evaporating surface of young bark, must certainly perish from exposure to a hot dry atmosphere. The cambium, or gelatinous matter, which is discovered between the bark and the wood when they are separated, is a mass of organizable cells. Mr. Paxton, using the gardener's expression, calls it the "pulp." Budding is most successfully performed when this matter is abundant, for then the vitality of the tree is in greatest degree of exaltation.
The individuality of the bud was sufficiently argued in the first section of this chapter, it need not now be again introduced, except as appropriately to remind us of the fact where the propagation depends upon this circumstance—the future tree must spring from the single bud which is inserted. Mr. A.T. Thomson, in his Lectures on the Elements of Botany, page 396, says:—"The individuality of buds must have been suspected as early as the discovery of the art of budding, and it is fully proved by the dissection of plants. * * Budding is founded on the fact, that the bud, which is a branch in embryo, is a distinct individual. It is essential that both the bud and the tree into which it is inserted should not only be analogous in their character, as in grafting with the scion, but both must be in a state of growth at the time the operation is performed. The union, however, depends much more upon the bud than upon the stock—the bud may be considered a centre of vitality—vegetative action commences in the bud, and extends to the stock, connecting them together."—"The vital energy, however, which commences the process of organization in the bud, is not necessarily confined to the germ, nor distinct from that which maintains the growth of the entire plant; but it is so connected with organization, that when this has proceeded a certain length, the bud may be removed from the parent and attached to another, where it will become a branch the same as if it had not been removed."
The season for budding has already been indicated in general terms, it is usually done in mid-summer and the early part of autumn, reference being had to the condition of the plants to be worked; these should be in a thrifty growing state, the woody fibre should be pretty well advanced, but growth by extension must still be active, or the needful conditions will not be found. The "pulp" must be present between the bark and the wood of the stock, so that the former can be easily separated from the latter; in the language of the art, the bark must "run;" this state of things will soon cease in most stocks, after the formation of terminal buds on the shoots. The success of spring budding, however, would appear to indicate that the cambium layer is formed earlier in the season than is usually supposed; for whenever the young leaves begin to be developed on the stock, "the bark will run," and the buds may be inserted with a good prospect of success. In this case we are obliged to use dormant buds that were formed the previous year, and we have to exercise care in the preservation of the scions, to keep them back by the application of cold, until the time of their insertion.
The condition of the bud is also important to the success of the operation. The tree from which we cut the scions should be in a growing state, though this is not so essential as in the case of the stock, as has been seen in spring budding—still, a degree of activity is desirable. The young shoot should have perfected its growth to such an extent as to have deposited its woody fibre, it should not be too succulent; but the essential condition is, that it should have its buds well developed. These, as every one knows, are formed in the axils of the leaves, and, to insure success, they should be plump and well grown. In those fruits which blossom on wood shoots of the previous year's growth, as the peach and apricot, the blossom buds should be avoided; they are easily recognized by their greater size and plumpness. In cutting scions, or bud-sticks, the most vigorous shoots should be avoided, they are too soft and pithy; the close jointed firm shoots, of medium size, are much to be preferred, as they have well developed buds, which appear to have more vitality. Such scions are found at the ends of the lateral branches. These need immediate attention, or they will be lost. The evaporation of their juices through the leaves would soon cause them to wither and wilt, and become useless. These appendages are therefore immediately removed by cutting the petioles from a quarter to half an inch from the scion; a portion of the stem is thus left as a convenient handle when inserting the shield, and this also serves afterward as an index to the condition of the bud. So soon as trimmed of their leaves, the scions are tied up, and enveloped loosely in a damp cloth, or in moss, or fresh grass, to exclude them from the air. If they should become wilted, they must not be put into water, as this injures them; it is better to sprinkle the cloth and tie them up tightly, or they may be restored by burying them in moderately moist earth.