[10] Balfour's Manual.
[11] Balfour's Manual, p. 284.
CHAPTER III.[ToC]
PROPAGATION.—SECTION I.
ALL GROWTH IS DEPENDANT UPON THE DEVELOPMENT OF CELLS—THE SEED AND THE BUD; THEIR RESEMBLANCE—THE INDIVIDUALITY OF BUDS—THE BASIS OF ALL PROPAGATION—BUDS ARE DEVELOPED INTO TWIGS; HAVE POWER OF EMITTING ROOTS—IMPORTANCE OF THE STUDY OF CELL-GROWTH—BY CUTTINGS: PREPARATION AND SELECTION—HEEL-CUTTINGS—SOFT WOOD—HARD WOOD—SEASONS FOR EACH—FALL PLANTING—THE CALLUS, OR DEVELOPMENT OF CELL-GROWTH—BOTTOM HEAT; WHY BENEFICIAL—WHY SPRING CUTTINGS FAIL—STIMULUS OF LIGHT UPON THE BUDS, CAUSES THEM TO EXPAND, AND THE LEAVES EVAPORATE TOO FREELY—ROOT CUTTINGS; DIFFERENT FRUITS THUS PROPAGATED—BY SUCKERS: OBJECTIONS TO ANSWERED—SUCKER ORCHARDS; BEAR EARLY—SUCKER TREES APT TO SUCKER AGAIN—BY LAYERS: A NATURAL METHOD—HOW PERFORMED—THE RASPBERRY AND THE GRAPE—ILLUSTRATIONS OF NATURAL AND ARTIFICIAL METHODS—QUINCE STOCKS—ADJUVANTS TO LAYERING, NOTCHING, ETC—BY SEEDS: HOW IT DIFFERS FROM THE OTHERS—APPLE SEEDLINGS—THEIR TREATMENT, SEPARATING, AND PREPARING THE SEED—APPARATUS—SPROUTING—SOWING—CULTIVATION—SEEDLINGS—TREATMENT—SORTING—PACKING.
All propagation of plants must depend upon the development of seeds or of buds, and all will arise from the growth and extension of cells. The seed and the bud are much more nearly related than a casual observer would at first sight suppose. The early phylologists thought they discovered that in the seed was enwrapped the image of the future tree—a dissection of the seed would appear to demonstrate this. It is composed of separate parts which are capable of being developed into the root, stem, and appendages, but they have yet to be so developed; the several parts that we find in the seed are merely the representative parts. But the seed has the future of the tree within itself, it has certain qualities of the future tree impressed upon it in its primary organization, within the capsule of the fruit of the parent plant, so that in a higher sense the image of the future tree does exist within the seed. Within the bud, still more plainly and more distinctly visible, is the future tree manifest, and we may produce a tree from a bud as certainly as we do from a seed. Subjected to circumstances favorable for growth, the bud, as well as the seed, will emit roots, will form its stem, branches and appendages, and will become a tree; differing from the product of the seed only in this, that in the latter the resulting organism constitutes a new individual which may vary somewhat from its parent, in the former it is only a new development of a part of a previously existing organization. The similarity existing between the two is exceedingly close, and is a matter of great importance in horticultural operations. Dr. Lindley, in the Gardener's Chronicle, says very truly, that "every bud of a tree is an individual vegetable, and a tree, therefore, is a family or swarm of individual plants, like the polype with its young growing out of its sides, or like the branching cells of the coral insect." Similar opinions, more or less modified, have been expressed by subsequent physiologists, and are familiar to men of science in every country and, we may add, are also universally accepted as true by all who claim a right to express an opinion upon the subject.—Men of science recognize the individuality of buds.—Nobody doubts the individuality of buds.—In a gardening aspect, the individuality of buds is the cardinal point upon which some of our most important operations turn; such, for example, as all modes of propagation whatever, except by seed. If this be not fully understood, there is no possible explanation of the reasons why certain results are sure to follow the attachment of a bud, or the insertion of a graft, or the planting of a cutting, or the bending of a layer, or the approach of a scion, or the setting of an eye—our six great forms of artificial multiplication. In his Elements of Botany, the same writer says: "An embryo is a young plant produced by the agency of the sexes, and developed within a seed—a leaf bud is a young plant, produced without the agency of the sexes, enclosed within the rudimentary leaves called scales, and developed on a stem." "An embryo propagates the species, leaf-buds propagate the individual." He shows each to be "a young plant developing itself upwards, downwards and horizontally, into stem, root, and medullary system."
Dr. Schleiden thus beautifully expresses his views of their individuality: "Now the bud essentially is nothing more than a repetition of the plant on which it is formed. The foundation of a new plant consists equally of a stem and leaves, and the sole distinction is that the stem becomes intimately blended at its base with the mother plant in its growth, and has no free radical extremity like that exhibited by a plant developed from a seed. However, this distinction is not so great as at the first glance it appears. Every plant of high organization possesses the power of shooting out adventitious roots from its stem, under the favoring influences of moisture; and very frequently, even plants that have been raised from seed, are forced to content themselves with such adventitious roots, since it is the nature of many plants, for instance the grasses, never to develop their proper root, although the radicle is actually present. We are, it is true, accustomed to look upon the matter as though the buds must always be developed into twigs and branches, on and in connection with the plant itself; and thus in common life, we regard them as parts of a plant, and not as independent individuals, which they are in fact, although they, like children who remain in their paternal home, retain the closest connection with the plant on which they were produced. That they are at least capable of becoming independent plants, is shown by an experiment frequently successful when the necessary care is taken, namely the breaking off and sowing of the buds of our forest trees. The well-known garden operations of grafting and budding are also examples of this, and layering only differs from the sowing of the buds, in that the buds on the layers are allowed to acquire a certain degree of maturity before they are separated from the parent plant. All here depends upon the facility with which these bud plants root as it is called, that is develop adventitious roots, when they are brought in contact with moist earth. * * * Nature herself very often makes use of this method to multiply certain plants in incalculable numbers. In a few cases, the process resembles the artificial sowing of buds, as when the plant spontaneously throws off the perfect buds at a certain period; an instance of this is afforded by some of our garden Lilies, which throw off the little bulb-like buds which appear in the axils of the lower leaves. The more common mode of proceeding is as follows: Those buds which have been formed near the surface of the soil, grow up into shoots provided with leaves; but the shoots are long, slender and delicate, the leaves too are stunted into little scales; in their axils, however, they develop strong buds, which either in the same or in the following year take root, and the slender shoot connecting them with the parent plant, dying and decaying, they become free independent plants. In this manner the strawberry soon covers a neglected garden."[12]