Peach

Peach, the name of a fruit tree which is included by Bentham and Hooker (Genera plantarum, i. 610) under the genus Prunus (Prunus persica); its resemblance to the plum is indeed obvious. Others have classed it with the almond as a distinct genus, Amygdalus; while others again have considered it sufficiently distinct to constitute a separate genus, Persica. In general terms the peach may be said to be a medium-sized tree, with lanceolate, stipulate leaves, borne on long, slender, relatively unbranched shoots, and with the flowers arranged singly, or in groups of two or more, at intervals along the shoots of the previous year's growth. The flowers have a hollow tube at the base bearing at its free edge five sepals, an equal number of petals, usually concave or spoon-shaped, pink or white, and a great number of stamens. The pistil consists of a single carpel with its ovary, style, stigma and solitary ovule or twin ovules. The fruit is a drupe (fig. 1) having a thin outer skin (epicarp) enclosing the flesh of the peach (mesocarp), the inner layers of the carpel becoming woody to form the stone, while the ovule ripens into the kernel or seed. This is exactly the structure of the plum or apricot, and differs from that of the almond, which is identical in the first instance, only in the circumstance that the fleshy part of the latter eventually becomes dry and leathery and clacks open along a line called the suture.

The nectarine is a variation from the peach, mainly characterized by the circumstance that, while the skin of the ripe fruit is downy in the peach, it is shining and destitute of hairs in the nectarine. That there is no essential difference between the two is, however, shown by the facts that the seeds of the peach will produce nectarines, and vice versa, and that it is not very uncommon, though still exceptional, to see peaches and nectarines on the same branch, and fruits which combine in themselves the characteristics of both nectarines and peaches. The blossoms of the peach are formed the autumn previous to their expansion, and this fact, together with the peculiarities of their form and position, requires to be borne in mind by the gardener in his pruning and training operations. The only point of practical interest requiring mention here is the very singular fact attested by all peach-growers, that, while certain peaches are liable to the attacks of mildew, others are not. In the case of the peach this peculiarity is in some way connected with the presence of small glandular outgrowths on the stalk, or at the base of the leaf. Some peaches have globular, others reniform glands, others none at all, and these latter trees are much more subject to mildew than are those provided with glands.

The history of the peach almond and nectarine is interesting and important as regards the question of the origin of species and the production and perpetuation of varieties. As to the origin of the peach two views are held, that of Alphonse de Candolle, who attributes all cultivated varieties to a distinct species, probably of Chinese origin, and that adopted by many naturalists, but more especially by Darwin, who looks upon the peach as a modification of the almond.

In the first place, the peach as we now know it has been nowhere recognized in the wild state. In the few instances where it is said to have been found wild the probabilities are that the tree was an escape from cultivation. Aitchison, however, gathered in the Hazardarakht ravine in Afghanistan a form with different-shaped fruit from that of the almond; being larger and flatter. "The surface of the fruit," he observes, "resembles that of the peach in texture and colour; and the nut is quite distinct from that of the wild almond. The whole shrub resembles more what one might consider a wild form of the peach than that of the almond." It is admitted, however, by all competent botanists that the almond is wild in the hotter and drier parts of the Mediterranean and Levantine regions. Aitchison also mentions the almond as wild in some parts of Afghanistan, where it is known to the natives as "beda,m," the same word that they apply to the cultivated almond. The branches of the tree are carried by the priests in religious ceremonies. It is not known as a wild plant in China or Japan. As to the nectarine, of its origin as a variation from the peach there is abundant evidence, as has already been mentioned; it is only requisite to add the very important fact that the seeds of the nectarine, even when that nectarine has been produced by bud-variation from a peach, will generally produce nectarines, or, as gardeners say, "come true." Darwin brings together the records of several cases, not only of gradations between peaches and nectarines, but also of intermediate forms between the peach and the almond. So far as we know, however, no case has yet been recorded of a peach or a nectarine producing an almond, or vice versa, although if all have had a common origin such an event might be expected. Thus the botanical evidence seems to indicate that the wild almond is the source of cultivated almonds, peaches and nectarines, and consequently that the peach was introduced from Asia Minor or Persia, whence the name Persica given to the peach; and Aitchison's discovery in Afghanistan of a form which reminded him of a wild peach lends additional force to this view.

On the other hand, Alphonse de Candolle, from philological and other considerations, considers the peach to be of Chinese origin. The peach has not, it is true, been found wild in China, but it has been cultivated there from time immemorial; it has entered into the literature and folk-lore of the people; and it is designated by a distinct name, "to" or "tao," a word found in the writings of Confucius five centuries before Christ, and even in other writings dating from the 10th century before the Christian era. Though now cultivated in India, and almost wild in some parts of the northwest, and, as we have seen, probably also in Afghanistan, it has no Sanskrit name; it is not mentioned in the Hebrew text of the Scriptures, nor in the earliest Greek times. Xenophon makes no mention of the peach, though the Ten Thousand must have traversed the country where, according to some, the peach is native; but Theophrastus, a hundred years later, does speak of it as a Persian fruit, and De Candolle suggests that it might have been introduced into Greece by Alexander. According to his view, the seeds of the peach, cultivated for ages in China, might have been carried by the Chinese into Kashmir, Bokhara, and Persia between the period of the Sanskrit emigration and the Graeco-Persian period. Once established, its cultivation would readily extend westward, or, on the other hand, by Cabul to north-western India, where its cultivation is not ancient. While the peach has been cultivated in China for thousands of years, the almond does not grow wild in that country and its introduction is supposed not to go back farther than the Christian era.

On the whole, greater weight is due to the evidence from botanical sources than to that derived from philology, particularly since the discovery both of the wild almond and of a form like a wild peach in Afghanistan. It may, however, well be that both peach and almond are derived from some pre-existing and now extinct form whose descendants have spread over the whole geographic area mentioned; but this is a mere speculation, though indirect evidence in its support might be obtained from the nectarine, of which no mention is made in ancient literature, and which, as we have seen, originates from the peach and reproduces itself by seed, thus offering the characteristics of a species in the act of developing itself.

The treatment in horticulture of the peach and nectarine is the same in every respect. To perpetuate and multiply the choicer varieties, peaches and nectarines are budded upon plum or almond stocks. For dry situations almond stocks are preferable, but they are not long-lived, while for damp or clayey foams it is better to use certain kinds of plums. Double-working is sometimes beneficial; thus an almond budded on a plum stock may be rebudded with a tender peach, greatly to the advantage of the latter. The peach border should be composed of turfy mellow FIG. 1. - Fruit (drupe) of Peach cut lengthwise. e, Skin or epicarp. m,Flesh or mesocarp. s, Stone or endocarp, within which is the seed or kernel.

(3 nat. size.) loam, such as is suitable for the vine and the fig; this should be used in as rough a state as possible, or not broken small and fine. The bottom should slope towards the outer edge, where a drain should be cut, with an outlet, and on this sloping bottom should be laid a thickness of from 9 in. to 12 in. of rough materials, such as broken bricks or mortar rubbish, over which should be placed a layer of rough turf with the grassy side downwards, and then the good loamy soil to form the border, which should have a depth of about 2 ft. 6 in. The peach-tree is most productive when the roots are kept near the surface, and the borders, which should be from 8 ft. to 12 ft. wide, should not be cropped heavily with culinary vegetables, as deep trenching is very injurious. Sickly and unfruitful trees may often be revived by bringing up their roots within 5 or 6 in. of the surface. It is questionable whether it is not better, in cold soils and bleak situations, to abandon outdoor peach culture, and to cover the walls with a casing of glass, so that the trees may be under shelter during the uncongenial spring weather.

The fruit of the peach is produced on the ripened shoots of the preceding year. If these be too luxuriant, they yield nothing but leaves; and if too weak, they are incapable of developing flower buds. To furnish young shoots in sufficient abundance, and of requisite strength, is the great object of peach training and pruning. Trees of slender-growing, twiggy habit naturally fall most readily into the fan form of training, and accordingly this has generally been adopted in the culture of peaches and nectarines (fig. 2). The young tree is, in many cases, procured when it has been trained for two or three years in the nursery; but it is generally better to begin with a maiden plant - that is, a plant of the first year after it has been budded. It is FIG. 2. - Montreuil Fan Training then in ordinary practice headed down to five or six buds, and in the following summer from two to four shoots, according to the vigour of the plant, are trained in, the laterals from which, if any, are thinned out and nailed to the wall. If there are four branches, the two central ones are shortened back at the subsequent winter pruning so as to produce others, the two lower ones being laid in nearly at full length. In the following season additional shoots are sent forth; and the process is repeated till eight or ten principal limbs or mother branches are obtained, forming, as it were, the frame-work of the future tree. The branches may be depressed or elevated, so as to check or encourage them, as occasion may arise; and it is highly advantageous to keep them thin, without their becoming in any part deficient of young shoots. Sometimes a more rapid mode of formation is now adopted, the main shoots being from the first laid in nearly at full length, instead of being shortened. The pruning for fruit consists in shortening back the laterals which had been nailed in at the disbudding, or summer pruning, their length depending on their individual vigour and the luxuriance of the tree. In well-developed shoots the buds are generally double, or rather triple, a wood bud growing between two fruit buds; the shoot must be cut back to one of these, or else to a wood bud alone, so that a young shoot may be produced to draw up the sap beyond the fruit, this being generally desirable to secure its proper swelling. The point of this leading shoot is subsequently pinched off, that it may not draw away too much of the sap. If the fruit sets too abundantly, it must be thinned, first when as large as peas, reducing the clusters, and then when as large as nuts to distribute the crop equally; the extent of the thinning must depend on the vigour of the tree, but one or two fruits ultimately left to each square foot of wall is a full average crop. The final thinning should take place after stoning.

The best-placed healthy young shoot produced from the wood buds at the base of the bearing branch is to be carefully preserved and in due time nailed to the wall. In the following winter this will take the place of the branch which has just borne, and which is to be cut out. If there be no young shoot below, and the bearing branch is short, the shoot at the point of the latter may sometimes be preserved as a fruit bearer, though if the bearing branch be long it is better to cut it back for young wood. It is the neglect of this which constitutes the principal fault in carrying out the English fan system, as it is usually practised. Several times during summer the trees ought to be regularly examined, and the young shoots respectively topped or thinned out; those that remain are to be nailed to the wall, or braced in with pieces of slender twigs, and the trees ought occasionally to be washed with the garden engine or thoroughly syringed, especially during very hot summers. After gathering the fruit all the wood not needed for extending the tree or for fruit bearing next season should be cut out so as to give the shoots left full exposure to air and light.

The Montreuil form of training is represented by fig. 2. The principal feature is the suppression of the direct channel of the sap, and the substitution of four, or more commonly two, mother branches, so laid to the wall that the central angle contains about 90°. The other branches are all treated as subordinate members. This form is open to the objection that, if the under branch should die, the upper one cannot be brought down into its place.

The form a la Dumoutier (fig. 3), so called from its inventor, is merely a refinement on the Montreuil method. The formation FIG. 3. - Dumoutier's Fan Training.

of the tree begins with the inferior limbs and proceeds towards the centre, the branches being lowered from time to time as the tree acquires strength. What is most worthy of notice in this method is the management of the e subordinates in the pruning for fruit. When a shoot promises blossom, it is generally at some distance from the point of insertion into the old wood, and the intermediate space is covered with wood buds. All the latter, therefore, which are between the old wood a and the blossoms c in fig. 4, except the lowest b, are carefully removed by rubbing them off with the FIG. 4. - Pruning a la finger. This never fails to produce Dumoutier. a shoot d, the growth of which is favoured by destroying the useless spray e above the blossoms, and pinching off the points of those which are necessary to perfect the fruit. A replacing shoot is thus obtained, too which the whole is invariably shortened at the end of the year.

Seymour's form (fig. 5) approaches more nearly to the French method than any other practised in England; but the direct channel FIG. 5. - Seymour's Fan Training.

of the sap is not suppressed, and this results in the production of branches of unequal vigour, which is very undesirable.

For cold and late situations, Thomas Andrew Knight recommended the encouragement of spurs on the young wood, as such spurs, when close to the wall, generate the best organized and most vigorous blossoms, and generally ensure a crop of fruit. They may be produced, by taking care, during the summer pruning or disbudding, to preserve a number of the little shoots emitted by the yearly wood, only pinching off the minute succulent points. On the spurs thus formed blossom buds will be developed early in the following season. This practice is well adapted to cold situations. Peachtrees require protection, especially at the period of blossoming, particularly in the north of England and in Scotland. Canvas or bunting screens are most effectual. By applying these early in the season, great benefit may be derived from retarding the blossom till the frosty nights of spring have passed. Wooden and glass copings are also very useful in warding off frosts. Care must be taken that the roots always have a sufficient supply of moisture and that the soil is moist wherever the roots run.