Fruits and Fruit Trees of America, pp. 1-5 (1845)
Andrew Jackson Downing
THE PRODUCTION OF NEW VARIETIES OF FRUIT.
IN our survey of the culture of fruits let us begin at the beginning. Gradual amelioration, and the skilful practice of the cultivator, have so filled our orchards and gardens with good fruits, that it is necessary now to cast a look back at the types from which these delicious products have sprung.
In the tropical zone, amid the surprising luxuriance of vegetation of that great natural hothouse, nature offers to man, almost without care, the most refreshing, the most delicious, and the most nutritive fruits. The Plantain and Banana, excellent either raw or cooked, bearing all the year, and producing upon a rood of ground the sustenance of a family; the refreshing Guava and Sapodilla; the nutritious Bread-fruit; such are the natural fruit trees of those glowing climates. Indolently seated under their shade, and finding a refreshing coolness both from their ever-verdant canopy of leaves, and their juicy fruits, it is not here that we must look for the patient and skilful cultivator.
But, in the temperate climates, nature wears a harsher and sterner aspect. Plains bounded by rocky hills, visited not only by genial warmth and sunshine, but by cold winds and seasons of ice and snow; these are accompanied by sturdy forests, whose outskirts are sprinkled with crabs and wild cherries, and festooned with the clambering branches 'of the wild grape. These native fruits, which at first offer so little to the eye, or the palate, are nevertheless the types of our garden varieties. Destined in these climates to a perpetual struggle with nature, it is here that we find man ameliorating and transforming her.
Transplanted into a warmer aspect, stimulated by a richer soil, reared from selected seeds, carefully pruned, sheltered and watched, by slow degrees the sour and bitter crab expands into a Golden Pippin, the wild pear loses its thorns and becomes a Bergamotte or a Beurré, the Almond is deprived of its bitterness, and the dry and flavourless Peach is at length a tempting and delicious fruit. It is thus only in the face of obstacles, in a climate where nature is not prodigal of perfections, and in the midst of thorns and sloes, that MAN THE GARDENER arises and forces nature to yield to his art.
These improved sorts of fruit which man every where causes to share his civilization, bear, almost equally with himself, the impress of an existence removed from the natural state. When reared from seeds they always show a tendency to return to a wilder form, and it seems only chance when a new seedling is equal to, or surpasses its parent. Removed from their natural form, these artificially created sorts are also much more liable to diseases and to decay. From these facts arises the fruit-garden, with its various processes of grafting, budding and other means of continuing the sort; with also its sheltered aspects, warm borders, deeper soils, and all its various refinements of art and culture.
In the whole range of cares and pleasures belonging to the garden, there is nothing more truly interesting than the production of new varieties of fruit. It is not, indeed, by sowing the seeds that the lover of fine fruit usually undertakes to stock his garden and orchard with fine fruit trees. Raising new varieties is always a slow, and, as generally understood, a most uncertain mode of bringing about this result. The novice, plants and carefully watches his hundred seedling pippins, to find at last, perhaps, ninety-nine worthless or indifferent apples. It appears to him a lottery, in which there are too many blanks to the prizes. He, therefore, wisely resorts to the more certain mode of grafting from well known and esteemed sorts.
Notwithstanding this, every year, under the influences of garden culture, and often without our design, we find our fruit trees reproducing themselves; and occasionally, there springs up a new and delicious sort, whose merits tempt us to fresh trials after perfection.
To a man who is curious in fruit, the pomologist who views with a more than common eye, the crimson cheek of a peach, the delicate bloom of a plum, or understands the epithets, rich, melting, buttery, as applied to a pear, nothing in the circle of culture, can give more lively and unmixed pleasure, than thus to produce and to create—for it is a sort of creation—an entirely new sort, which he believes will prove handsomer and better than any thing that has gone before. And still more, as varieties which originate in a certain soil and climate, are found best adapted to that locality, the production of new sorts of fruit, of high merit, may be looked on as a most valuable, as well as interesting result.
Beside this, all the fine new fruits, which, of late, figure so conspicuously in the catalogues of the nurseries and fruit gardens, have not been originated at random and by chance efforts. Some of the most distinguished pomologists have devoted years to the subject of the improvement of fruit trees by seeds, and have attained if not certain results, at least some general laws, which greatly assist us in this process of amelioration. Let us therefore examine the subject a little more in detail.
In the wild state, every genus of trees consist of one or more species, or strongly marked individual sorts; as, for example, the white birch and the black birch; or, to confine ourselves more strictly to the matter in hand, the different species of cherry, the wild or bird cherry, the sour cherry, the mazzard cherry, &c. These species, in their natural state, exactly reproduce themselves; to use a common phrase, they "come the same" from seed. This they have done for centuries, and doubtless will do forever, so long as they exist under natural circumstances only.
On the other hand, suppose we select one of these species of fruit-trees, and adopt it into our gardens. So long as we cultivate that individual tree, or any part of it, in the shape of sucker, graft, or bud, its nature will not be materially altered. It may, indeed, through cultivation, be stimulated into a more luxuriant growth; it will probably produce larger leaves and fruit; but we shall neither alter its fruit in texture, color or taste. It will always be identically the same.
The process of amelioration begins with a new generation, and by sowing the seeds. Some species of tree, indeed, seem to refuse to yield their wild nature, never producing any variation by seed; but all fruit-trees and many others, are easily domesticated, and more readily take the impress of culture.
If we sow a quantity of seed in garden soil of the common black mazzard cherry (Cerasus avium,) we shall find that, in the leaves and habit of growth, many of the seedlings do not entirely resemble the original species. When they come into bearing, it is probable we shall also find as great a diversity in the size, color and flavor of the fruit. Each of these individual plants, differing from the original type, (the mazzard,) constitutes a new variety; though only a few, perhaps only one, may be superiour to the original species.
It is worthy of remark, that exactly in proportion as this reproduction is frequently repeated, is the change to a great variety of forms, or new sorts increased. It is likely indeed, that to gather the seeds from a wild mazzard in the woods, the instances of departure from the form of the original species would be very few; while if gathered from a garden tree, itself some time cultivated, or several removes from a wild state, though still a mazzard, the seedlings will show great variety of character.
Once in the possession of a variety, which has moved out of the natural into a more domesticated form, we have in our hands the best material for the improving process. The fixed original habit of the species is broken in upon, and this variety which we have created, has always afterwards some tendency to make further departures from the original form. It is true that all or most of its seedlings will still retain a likeness to the parent, but a few will differ in some respects, and it is by seizing upon those which show symptoms of variation, that the improver of vegetable races founds his hopes.
We have said that it is a part of the character of a species to produce the same from seed. This characteristic is retained even where the sport, (as gardeners term it) into numberless varieties is greatest. Thus, to return to cherries, the Kentish or common pie-cherry is one species, and the small black mazzard another, and although a great number of varieties of each of these species have been produced, yet there is always the likeness of the species retained. From the first we may have the large and rich Mayduke, and from the last the sweet and luscious Black-Hearts; but a glance will show us that the duke cherries retain the distinct dark foliage, and, in the fruit, something of the same flavor, shape and color of the original species; and the heart cherries the broad leaves and lofty growth of the mazzard. So too, the currant and gooseberry are different species of the same genus; but though the English gooseberry growers have raised thousands of new varieties of this fruit, and shown them as large as hen's eggs, and of every variety of form and color, yet their efforts with the gooseberry have not produced any thing resembling the common currant.
Why do not varieties produce the same from seed? Why if we plant the stone of a Green Gage plum, will it not always produce a Green Gage? This is often a puzzling question to the practical gardener, while his every day experience forces him to assent to the fact.
We are not sure that the vegetable physiologists will undertake to answer this query fully. But in the mean time we can throw some light on the subject.
It will be remembered that our garden varieties of fruits are not natural forms. They are the artificial productions of our culture. They have always a tendency to improve, but they have also another and a stronger tendency to return to a natural, or wild state. "There can be no doubt," says Dr. Lindley, "that if the arts of cultivation were abandoned for only a few years, all the annual varieties of plants in our gardens would disappear and be replaced by a few original wild forms." Between these two tendencies, therefore, the one derived from nature, and the other impressed by culture, it is easily seen how little likely is the progeny of varieties always to reappear in the same form.
Again, our American farmers, who raise a number of kinds of Indian corn, very well know that, if they wish to keep the sorts distinct, they must grow them in different fields. Without this precaution they find on planting the seeds produced on the yellow corn plants, that they have the next season a progeny, not of yellow corn alone, but composed of every color and size, yellow, white and black, large and small, upon the farm. Now many of the varieties of fruit trees have a similar power of intermixing with each other while in blossom, by the dust or pollen of their flowers, carried through the air, by the action of bees and other causes. It will readily occur to the reader, in considering this fact, what an influence our custom of planting the different varieties of plum or of cherry together in a garden or orchard, must have upon the constancy of habit in the seedlings of such fruits.
But there is still another reason for this habit, so perplexing to the novice, who, having tasted a luscious fruit, plants, watches and rears its seedling, to find it perhaps, wholly different in most respects. This is the influence of grafting. Among the great number of seedling fruits produced in the United States, there is found occasionally a variety, perhaps a plum or a peach, which will nearly always reproduce itself from seed. From some fortunate circumstances in its origin, unknown to us, this sort, in becoming improved, still retains strongly this habit of the natural or wild form, and its seeds produce the same. We can call to mind several examples of this; fine fruit trees whose seeds have established the reputation in their neighborhood of fidelity to the sort. But when a graft is taken from one of these trees, and placed upon another stock, this grafted tree is found to lose its singular power of producing the same by seed, and becomes like all other worked trees. The stock exercises some, as yet, unexplained power, in dissolving the strong natural habit of the variety, and it becomes like its fellows, subject to the laws of its artificial life.
When we desire to raise new varieties of fruit, the common practice is to collect the seeds of the finest table fruits—those sorts whose merits are every where acknowledged to be the highest. In proceeding thus we are all pretty well aware, that the chances are generally a hundred to one against our obtaining any new variety of great excellence. Before we offer any advice on rearing seedlings let us examine briefly the practice and views of two distinguished horticulturists abroad, who have paid more attention to this subject than any other persons whatever; Dr. Van Mons of Belgium, and Thos. Andrew Knight, Esq., the late President of the Horticultural Society of London.