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all difficult to make live when transplanted, provided the branches or tops of the trees are reduced, to correspond with loss of roots in digging up at the time of
removal. It may be well to give a word of caution to the novice in nut culture about pruning nut trees in spring, after the sap begins to flow; for if done at this time they will bleed freely and leave unhealthy wounds and black, unsightly spots on the bark. Prune walnuts in summer or early in winter, to give time for the wounds to season before the buds swell in spring. If young trees are to be dug up, prune after they are taken from the ground, then the sap will not flow from the wounds. This is true of all deciduous trees, vines and shrubs. If the trees have few small roots when taken up, prune severely; but if roots are abundant, little pruning will be required. It is seldom, however, in transplanting walnuts, that the pruning need be as severe as recommended for the chestnut; in fact, having transplanted walnuts of various species, and of all ages from one to twenty years,
without the loss of a plant, I have FIG. 75. SEEDLING WALNUT. come to the conclusion that they are pretty safe trees to handle, in this climate, at least, if not elsewhere.
In seeking walnuts from a distance, for planting anywhere in the Middle or Northern States, it will be
Spain, Jew Ford 1
well to learn something in advance about the climate in which the nuts are raised; for it would be folly to send for either trees or nuts to a warm or semi-tropical region, like that of southern France or Spain, for a stock to cultivate in a climate as cold as that of New York, New Jersey, and States on the same line westward. We might, perchance, from such importation, secure one hardy plant in a hundred or thousand, but there would be no certainty of even this small number.
This idea of acclimation and adaptatior. of trees to conditions and climate should not be over ooked by the nut culturist, no matter from what source he procures his stock, whether from abroad, or some distant region of his own country. If it can be obtained from a region where it has been growing under conditions similar to those to which it is to be transferred for cultivation, then the chances of success will certainly be largely augmented. Acclimation is a slow process; in fact, too slow for us to expect to secure any appreciable advantages from it in a lifetime, but in nature we seek final results, leaving time out of the question.
In raising seedling trees we cannot expect much more than a reproduction of the species, and not that of the parent tree. Plants that have been subjected to unnatural conditions and surroundings, as usual under cultivation, are far more likely to show a wider range of variation in the seedlings than those growing wild in their native habitats; but even the latter cannot be depended upon to reproduce exact types from seed. In other words, there is nothing certain about seedling nut trees; the large nuts may produce trees bearing very small ones, the early-ripening give late ones, the tall dwarf trees and the precocious fruiting some of the most tardy vari. eties; and yet, with all this uncertainty, we still think it best to select for planting the best nuts obtainable, 3. e., best and most promising for the conditions under which the seedlings are to be grown.
For the multiplication and perpetuation of choice varieties we must resort to artificial modes of propagation, mainly by budding and grafting. These modes, however, while the best at present known, are so difficult and uncertain in cool climates,-even in the hands of the most skilful propagators,—that grafted walnut trees have never been very plentiful in the nurseries of this or other countries with which we have commercial relations. In the south of France nurserymen appear to have been more successful in the propagation of walnuts by budding and grafting, than elsewhere; but in the northern provinces, as well as in Great Britain, we hear little of this mode of propagation. So difficult has this mode of propagating the walnut been considered in England, that Thomas Andrew Knight, president of the London Horticultural Society, early in the present century discouraged all attempts to propagate this tree by such means; but later, in a paper read before the Society April 7, 1818, he admits to having changed his mind, especially in regard to budding the walnut, and says :
“The buds of trees of almost every species succeed with most certainty when inserted on the shoots of the same year's growth; but the walnut tree appears to afford an exception; possibly, in some measure, because its buds contain within themselves, in the spring, all the leaves which the tree bears in the following summer, whence its annual shoots cease to elongate soon after its buds unfold; all its buds of each season are also, consequently, very nearly of the same age, and long before any have acquired the proper degree of maturity for being removed, the annual branches have ceased to grow longer or to produce new foliage. ... To obviate the disadvantage arising from the preceding circumstances, I adopted means of retarding the period of the vegetation of the stocks comparatively with that of the bearing tree : and by these means I became partially successful. There are, at the base of the annual shoots of the walnut and other trees, where these join the year-old wood, many minute buds which are almost concealed in the bark, and which rarely or never vegetate but in the event of the destruction of the large prominent buds which occupy the middle and opposite end of the annual wood. By inserting in each stock one of these minute buds and one of the large prominent kind, I had the pleasure to find that the minute buds took freely, while the large all failed without a single exception."
From the above and other remarks of Mr. Knight, in the paper read by him, I infer that he kept the stocks in pots stored in a cool place in spring, until he could obtain shoots of the season from bearing trees, and from these minute undeveloped axillary buds for inserting in the stocks. These buds, as he informs us, are inserted in the wood of the preceding season, and near the summit or top. He does not give any directions for holding the buds in place, whether by waxed or plain bass ligatures; the former, however, would probably be preferable, for the purpose of excluding the air and water.
Some twenty years later (1838) J. C. Loudon, in “Arboretum Britannicum,” etc., refers to the propagation af the walnut as follows: “Much has been written on the subject by French authors, from which it appears that in the north of France, and in cold countries generally, the walnut does not bud or graft easily by any mode; but that in the south of France and north of Italy it may be budded or grafted by different modes, with success. At Metz, the Baron de Tschoudy found the flute method (Fig. 76) almost the only one which he could practice with success. . By this mode an entire ring of bark, containing one or more buds, is removed
freely from that the bark coon this ring
from a twig on a tree to be multiplied, and transferred to the stock, and made to fit as shown. If the ring is too large, a slice may be cut off ; and if too small, a piece of the bark of the stock may be left to fill the space." Both stock and parent tree must be in about the same condition or stage of growth when this ring budding is done, in order that the bark containing the bud may peel off freely from the wood, and this is always
in the spring, soon after the buds begin to unfold and the sap is in motion. Loudon says that in Dauphine, France, young plants in the purseries are budded chiefly by this mode, which succeeds best the closer the operation is performed to the collar of the plant; and the same is true in grafting, the nearer the root the better, as has been found by experience with hickories.
Charles Baltet, in his “L’Art de Greffer,” recommends grafting in the usual mode of crown grafting, also flute' or ring grafting, in April or May, and ordinary cleft grafting close
to the root and at the forks of the FIG. 76. branches, etc. He says that the cion FLUTE BUDDING. should be cut, as much as possible, obliquely across the pith, so that it may be exposed on one side only. He also advises using cions whose base consists of wood of two years' growth, and these furnished with a terminal bud. He cautions propagators against grafting early-growing kinds upon those of later vegetation. If walnuts of any of the native or foreign species have been successfully propagated by budding or grafting, at any of the nurseries in our Eastern States, it has not been made known in the nurserymen’s catalogues.