American Pomology. Apples

by J. A. Warder

THINNING.

PROFUSION OF FRUIT-BUDS—WISE PROVISION AGAINST ACCIDENTS—PERIOD OF MATURITY OF PLANTS—MORPHOLOGY—THE YOUNG PLANT GROWS BY DEVELOPMENT OF STEM AND BRANCHES—LEAF BUDS ALL POINTED—THE PERIOD OF ADOLESCENCE VARIES—THE CENTURY PLANT—A DEFINITE PERIOD FOR EACH VARIETY—HOW DIMINISHED OR EXTENDED—STARVING—CROWDING—CUTTING THE ROOTS—OLD OR UNCONGENIAL STOCKS—AT MATURITY AN ACCUMULATION OF NUTRITIVE MATTER—PRESERVING THE BALANCE BETWEEN GROWTH AND FRUITAGE—WE DO NOT THIN FRUIT ENOUGH—TREES EXHAUST THEMSELVES—BIENNIAL BEARERS—ANNUAL BEARERS DESIRABLE—DISBUDDING—FIELD'S HEDGES OF PEARS—REMOVE PORTIONS OF FRUIT—CUTTING-IN THE SHOOTS TO REDUCE FRUIT—DR. HULL AND OTHERS—THINNING THE STRAWBERRY—GOOSEBERRY—GRAPE—THINNING APPLES BY THRESHING THE TREES—BY SEVERE WINTER PRUNING.

Every person who has looked at a bearing fruit tree in the winter season, must have been struck with wonder at the great profusion of fruit-buds with which it was clothed; they are crowded along the slender spray of some varieties as thickly as a necklace of beads, or still more abundantly, like clusters of pearls, they are crowded together upon the little fruit-spurs. We are inclined to cavil at this profusion of nature, and to ask why this waste of vegetative effort. But we may rest assured that it is only another evidence of the unerring wisdom of Him who doeth all things well.

All blossoming and fruiting is but a changed condition of those buds that would otherwise have produced leaves and wood-growth. Every tree, sooner or later, reaches a point which we call its period of maturity, when some of its buds are thus modified. The same elemental parts are still present; but those that were arranged for the production of an elongated shoot, with leaves set around it in some definite manner, and destined for the formation of woody growth, are now so constituted as to have a growth of very short extension, and furnished with modified leaves, so changed, that we scarcely recognize them thus crowded together upon this shortened and modified axis. We here take our first lesson in the very interesting study of morphology, or the science of the changes of form to which the parts of a plant are subjected, in the production of flowers and fruit, from what were otherwise the source of shoots and leaves. This will be found one of the most interesting branches of the study of botany, as it leads us to the investigation of one of the most beautiful displays of Divine power, and, like all such studies, gives us more and more elevated views of the exalted wisdom and benevolence of an All-wise Creator, who has produced nothing in vain, and who, while creating worlds and systems of the greatest magnificence, has condescended to prepare the most tiny flower, and its previous bud, in the most perfect manner.

The study of morphology which gives us such an insight into the mechanism of the plant, and which leads us into such mazes of wonder and admiration, cannot now detain us further than to be named and referred to as the explanation of the formation of what we call fruit or blossom buds. The reader is referred to the full explanations of this subject by the famous philosopher and poet, Goethe; or, if more conveniently accessible, to his English translators, or to the appropriate chapters in any of the modern text books of botany.

When the plant is young, its chief object is to grow; it must acquire size and development, to enable it to produce and bear up the enormous crop it is destined one day to yield. Hence in the early years of a tree there is none, or very little of this transformation of the buds, which are all of the pointed character, and when excited into growth, they all produce shoots and leaves only, which result in the formation of an increase of the woody fabric, that we call the tree. This period of adolescence is longer or shorter in different species and varieties—in some it may extend through many years. Thus, the American Aloe is called the Century Plant, from the common belief that it must survive a hundred summers before this stage of maturity and blossoming is reached; whereas this plant only needs a period of thirty years or less to produce its blossoms, when it is favorably situated as to soil and climate.

There is, it is probable, a definite period at which each kind of plant will have these changes occur in the buds, when they will begin to flower and to produce fruit. This period may be accelerated or retarded, to some extent, by human means; for we have observed, that whatever produces excessive vigor, is attended with the formation of leaf buds; whereas, all those conditions and circumstances that check the vigorous growth by extension, provided they do not too greatly impair the vitality of the plant, will conduce to the formation of flower-buds.

Some of these conditions consist in starving the tree, or by planting it in a sterile soil, that has deficient moisture; by severely crowding the roots, or by cutting them, as in root pruning; in grafting a portion of the young plant upon an old or an uncongenial stock, or one that is naturally dwarfish; in ringing the bark; in frequent transplanting, or in continued summer pinching; in short, almost any circumstances which appear to threaten the life of the tree, seem to excite within it an effort for the preservation and perpetuation of the species, by changing the bud plants, attached to the parent, into seed plants, that may and will be separated from it to reach the soil eventually, and there to establish an independent existence.

As the tree advances in growth, and approaches toward its natural period of maturity, it is supposed that there is an accumulation of nutritive matter within it, and at the same time the roots will have exhausted the soil, to some extent, of the elements that contributed to the production of wood-growth, and the result is the formation of flower-buds. Now it becomes a nice matter to preserve the proper balance between these two systems of growth, the wood producing and the fruit forming. Two opposite systems of production have become established in the tree, the one infertile, the other producing the desired fruits; the one preserving the health and vigor of the tree, the other tending to preserve the species at the same time that it satisfies our demands for fruit, but also meanwhile tending to the destruction of the tree, for all old trees are apt to overbear. Young trees, on the contrary, in which the vigor of wood-growth remains in full activity, very often produce fruit-buds and blossoms, but do not perfect their fruit, which either fails to set, from some imperfection of the organs of reproduction, or falls prematurely, in consequence of the wood system absorbing the nutriment, or failing to prepare the proper juices for their support. Trees, in these different conditions, require an entirely opposite treatment. The younger need summer pruning and pinching, to check their too great vigor, and to develop the laterals or spurs with their blossom buds; the older need winter pruning, for the double purpose of reducing the amount of fruit, and also to excite renewed vigor in the production of wood growth that shall take the place of that which has been removed. This subject will be more appropriately discussed in another chapter, to which the reader is referred; while we proceed to the legitimate topic of thinning fruit.

Thinning fruit is not practiced as it should be, particularly on the apple; old trees are often too fruitful, so much so as not only to deteriorate the fruit, but to injure the tree itself. This is so much the case with certain varieties, as to constitute a serious objection to planting them; other sorts so exhaust themselves by over-production in one season, as to be barren, or nearly so, the next year, during which period of rest they are able to recuperate their energies and to provide a new set of flower-buds. These are called biennial bearers, and such are quite numerous in our orchards. Those kinds that are prone to overbear every year, are often objectionable on account of the diminished size and inferior character of their fruits, which result from this cause, particularly when the trees have become old. The great desideratum, especially with those who object to the trouble of thinning the fruit, is to find a variety that will produce an even or well distributed, continuous, and moderate yield—an annual bearer, that does not exhaust itself by the production of one enormous crop so as to require it to rest and recuperate. Such varieties are to be found in our collections, and should be highly prized.