American Pomology Part 4

We say, as a general rule, that stone fruits must be grafted upon stone fruits, those bearing seeds, upon seed fruit; but there are limits even here which confine us upon one hand, and give us more lat.i.tude upon the other. Thus the cherry may be worked upon the wild cherry (_Prunus Virginiana_) but it forms a very poor union; the pear will grow upon the thorn, which has a very different seed, but the union is very imperfect and the tree is short-lived; the apple would appear to be much nearer of kin, since it belongs to the same genus, but though the pear will grow vigorously upon this stock, it is no more permanent than upon the thorn: either of them will answer when grafted low, or in the root, to start the cutting, as the scion may then be considered, and to sustain it until it shall have supplied itself with roots. In top-grafting the pear upon a tree of either species, it is found essential to success, and it conduces to the greater durability of the tree, for some branches of the original stock to be left intact to secure the circulation of the trunk, as the union of the dissimilar cells is so imperfect that it does not furnish sufficient vent for the sap. In the case of the cherry we find that the varieties appear to have a greater affinity for those of their own race; thus the Dukes and Morellos do well when grafted upon the Morello stocks, whereas the Hearts and Bigarreau sorts do not make a good union upon these stocks, but prefer the Mazzard, which has a freer growth more like their own. Most varieties will do well upon the Mahaleb stock, which is used as a means of dwarfing this fruit, though not a dwarf. Upon the wild cherry, which belongs to quite a different section of the genus, the cultivated varieties will grow, but they form a very imperfect union.

The peach may be worked upon the plum stock, and is claimed to be somewhat dwarfed by it, and to produce superior fruit. This stock is more congenial to the apricot, which is frequently propagated upon it.

Both plums and apricots may be worked upon the peach stock, and they will grow very vigorously, as they will upon the wild plum, but they soon over-grow, and are very apt to break off. When either of these species is used as a stock for the plum or apricot, they should be considered merely as a nursing mother, like the apple or thorn to the pear, which may be wanted to help the cutting until it shall be prepared to stand alone, and feed itself from its own roots. In other words, they should be grafted, _not budded_, into these uncongenial stocks, and the operation should be performed in the collar or below it, in the root, so that the growing scion may be earthed up, and encouraged to furnish itself with a good system of roots of its own.

The success will then depend upon the ability of the scion to emit roots freely.

We must never forget that in grafting, we are confined to very narrow limits. Our scion must be of a similar nature with the stock, each must have cells of a similar character, capable of transmitting their nutritious fluids from one to the other. We must recollect likewise, that the parts must be so co-apted that the cells of wood growth shall be brought into as close connection as possible, in both scion and stock; these cells are found in the layer, called the cambium, which is between the wood and the bark. The crude sap from below will often pa.s.s from cell to cell, when the elaborated sap of the cells in the scion is wholly unfitted for the formation of wood cells in the stock below it; of course the union in such a case must be very imperfect, and the product of such a grafting will be subject to accident, and will be short-lived, though the result in fruit, while the union continues, may be very precocious, abundant, and of superior flavor.

Natural grafting may often be observed by the student of nature when wandering among his favorites of the sylvan shades. There can be no doubt that the first hint was thus communicated to the early gardeners. In nature we always find the grafting to be inarching, or grafting by approach; two limbs or even two trees approximating closely, have abraded one another, and have afterward united their tissues most firmly together. This is generally a union of two trees of the same variety or species; but such is not always the case; sometimes trees of very dissimilar natures unite in this manner, but when we examine them we find only a dove-tailing, only a mechanical union, but no vital action subsists between them. The ancients give us some fancy sketches of the unions by grafting of very dissimilar trees, and some moderns who have no higher claim to poetry than their romancing, tell us that we may graft the peach upon the Willow and b.u.t.tonwood, and form other equally impossible unions.

The different methods of performing the operation of grafting vary with the character and size, and condition of the stocks to be worked; thus we have splice grafting, whip, cleft, saddle, and side grafting with modifications, and also grafting by approach, which is generally called inarching--though sometimes also practiced where we desire to renew the roots of a tree that are unhealthy, or to restore those that have been removed by accident or by the erosion of some rodent animals.

[Ill.u.s.tration: Fig. 7.]

SPLICE GRAFTING is the simplest process, and is applicable only where the size of the stock and of the scion correspond pretty nearly; the two are cut with a sloping curve, each of which being made at the same angle, will coincide with the other when they are applied together, as represented in the engraving, fig. 7.

[Ill.u.s.tration: Fig. 8.--WHIP GRAFTING.]

WHIP GRAFTING is a modification of the above. Each portion is cut in a sloping manner as in the splice grafting, but each is also split with a thin-bladed knife, as represented in fig. 8. The object in this is to give a firmer union to the two portions, and also to present a more extended surface for the effusion of the new cell tissue that is to form the bond of union in cementing them together. In both these methods, but especially in the first, the parts must be held together in co-aptation by some kind of bandage; this is generally composed of grafting wax, spread upon cloth or paper, or even, as now extensively practiced, upon fine thread. Cotton yarn _No_. 3 is drawn through melted grafting wax, and as it cools, it is wound upon a reel at the other side of the room, whence it is drawn as wanted by the grafter or tyer. Tying or wrapping is always a good precaution, and when the splice or cleft graft is not very close, it becomes necessary; but thousands of grafts will unite equally well where the parts are covered with earth, without any such appliance.

[Ill.u.s.tration: Fig. 9.--DIFFERENT STEPS IN CLEFT GRAFTING. _A_, SCION PREPARED FOR SETTING. _B_, THE CLEFT OPENED BY A WEDGE.

_C_, THE SCION INSERTED. _D_, SECTION OF STOCK AND SCION TO SHOW THE CO-APTATION OF THE PARTS OF THE TWO.]

[Ill.u.s.tration: Fig. 10.--CLEFT GRAFTING WITH BOTH SCIONS INCLINED INWARD.]

CLEFT GRAFTING is generally done when the stock is larger than the scion, and also where the operation is performed at a point above the ground. The stock is split downward, after having been cut off at the point where the grafting is to be done. The knife should be sharp, and the bark should be cut through first, to avoid its being torn, and so that the sides of the cleft shall be smooth. A wedge is inserted to keep the cleft open for the insertion of the scion, which is cut on each side like a fine wedge; but the two planes not being parallel, the bark will be left on one side to the very point of the wedge, while on the other it will be removed a part of the way, making a feather edge, _A_, fig. 9. The object of this is to have the pressure of the cleft greatest upon the outer side, where the union is to be effected. It is well to have a bud on the strip of bark left between the two cuts used in forming the graft, this should be near the top of the cleft. One or two grafts may be inserted into a cleft, or more clefts may be made, in large stocks, or in re-grafting the large limbs of an old tree, but usually one is sufficient to leave growing; and in the young tree, only one should ever be allowed to remain. When the scion is nicely set into the cleft, so that the inner bark of the stock and graft shall coincide, or rather cross a very little, (see fig. 10,) the wedge, whether of hard wood, or of iron, should be gently withdrawn, and then the elasticity of the stock will hold the scion firmly to its place; this pressure should not be too severe. In this kind of grafting, if the pressure be sufficiently firm, and if the operation have been performed below the surface of the ground, it may not be necessary to make any other application than to press the moist earth about the parts, and cover all but the top of the graft with soil, and place a stick to indicate the plant and protect it from injury. If, on the contrary, the pressure of the cleft be not sufficient to hold the scion firmly, as in small stocks, the graft must be tied. For this a piece of ba.s.s matting, or cotton twine, may be used; and if the operation has been performed above ground, the whole must be covered with grafting wax, applied, either hot with a brush, or cold, after having been worked with the hands, or by wrapping with strips of muslin or paper previously spread with the wax. In old times grafting clay was used, and applied with the hands as a lump around the junction; but this disagreeable and clumsy appliance has given way to more elegant and convenient arrangements.

[Ill.u.s.tration: Fig. 11--SIDE GRAFTING.]

[Ill.u.s.tration: Fig. 12--SIDE GRAFTING--THE STOCK NOT CUT BACK.]

[Ill.u.s.tration: Fig. 13.--TWO FORMS OF SIDE GRAFTING.--_A_, _B_, THE SCION AND STOCK FOR THE RICHARD SIDE GRAFT. _C_, STOCK FOR THE GIRARDIN SIDE GRAFT. _D_, SCION, AND _E_, FRUIT BUD FOR THE SAME.]

SIDE GRAFTING is performed in two ways. In one it is a modification of cleft grafting in which there is no cleft, but the bark is started from the wood, and the scion, cut as shown in figure 11, is pressed down between the wood and bark. This can only be done late in the spring, after the sap has begun to flow in the stock, so that the bark will run; it is indeed more like budding than grafting. The other modification is done without cutting off the stock. The knife is applied to the side of a stock of medium size, and a cut is made downward and extending to one-third the diameter, fig. 12; the scion is cut as for cleft grafting, and inserted so as to have the parts well co-apted, and then secured as usual. This plan is useful where there is danger of too free a flow of sap from the roots. Two other kinds of side graft are shown in fig. 13. The left-hand figures show the Richard side graft, in which an arched branch, _A_, is used. This is inserted under the bark of the stock, _B_; above the graft an incision is made in the stock down to the wood, to arrest the flow of sap. After the insertion, the wound is covered with grafting wax. The Girardin side graft is ill.u.s.trated at the three right-hand figures. A fruit bud, _E_, or a graft with a terminal fruit bud, _D_, is inserted under the bark of the stock, _C_, in August, or whenever suitable buds can be obtained and the bark will run. The wound is tied and covered with wax, as before. The object of this grafting is to secure immediate fruitage. Another kind of side grafting consists in plunging a dirk-shaped knife directly through the tree, inclining the point downward, into this opening the graft is inserted; the object being to establish a limb on a naked portion of the trunk.

[Ill.u.s.tration: Fig. 14.--SADDLE GRAFTING.]

SADDLE GRAFTING is used only with stocks of small size; it is performed by making a double slope upon the stock, and by opening a corresponding s.p.a.ce in the graft, by cutting two slopes in the scion, from below upwards, so that they shall meet in the centre, as seen in _fig._ 14. Some merely split the scion.

GRAFTING BY APPROACH, or as it is generally termed, _inarching_, is often practiced where there is difficulty in making the scion unite with the stock; it is not often needed in the culture of our orchard fruits, but may be here described. The stock upon which we wish to graft the scion, must be planted near the variety or species to be increased. A small twig of the latter, which can be brought close to the stock, is selected for the operation; a slice of bark and wood is then removed from the twig, and another of equal size from the stock, so managed, that these cut surfaces can be brought together and secured in that position until they have united, after which the twig, that has been used as a scion, is cut from its parent tree, and the top of the stock is carefully reduced until the scion has sufficiently developed itself to act as the top of the ingrafted tree, which may afterward be transplanted to its proper station.

A modification of this grafting by approach, is, however, sometimes of great service, where we have a valuable tree that has suffered from disease in the roots, or from injury to them. It consists in planting some thrifty young stocks, with good roots, about the base of the tree, after having prepared the ground by thorough digging, and by the addition of good soil if necessary. These stocks are then inserted upwards into the healthy portion of the trunk, by the process of side grafting reversed or inverted, or by the usual method of inarching.

RING GRAFTING OR BARK GRAFTING is not much used, and in small stocks it is rather a kind of budding, for then a ring of bark is removed at the proper season of year, generally about midsummer, and it is replaced by a similar ring of bark from a shoot of the same size, taken from a tree of the variety to be propagated; this ring of bark must be furnished with a healthy bud. This method has little to recommend it, and can only be applied when both the stock and the scion are in a growing condition, so that the bark will run freely; care also must be exercised to avoid injuring the eye of the bud, in peeling off the ring. A modification of bark grafting may be applied with great advantage, however, to an old tree, that has met with an injury to a portion of its bark. The injured part should be pared smoothly to the sound bark and wood. This may be done with a sloping cut, or the edge may be made abrupt and square with a chisel and mallet; a piece of fresh wood and bark is then to be cut from a healthy tree and fitted precisely to the fresh wound, and secured in its place with bandages, and grafting clay or wax is then applied, thus making what the surgeons would call a sort of taliacotian operation. Instead of a single piece of wood and bark, a number of young shoots may be used to make the communication complete; these are set close together and secured in the usual manner; see fig. 15.

[Ill.u.s.tration: Fig. 15.--BARK GRAFTING, TO REPAIR AN INJURED TREE.]

RE-GRAFTING OLD ORCHARDS.--Old orchards of inferior fruit may be entirely re-made and re-formed by grafting the limbs with such varieties as we may desire. A new life is by this process often infused into the trees, which is due to the very severe pruning which the trees then receive; they are consequently soon covered with a vigorous growth of young healthy wood, which replaces the decrepid and often decaying spray that acc.u.mulates in an old orchard, and the fruit produced for several years by the new growth is not only more valuable in kind, according to the judgment used in the selection of grafts, but it is more fair, smooth and healthy, and of better size than that which was previously furnished by the trees. Certain varieties are brought at once into bearing when thus top-grafted, which would have been long in developing their fruitful condition if planted as nursery trees. Others are always better and finer when so worked, than on young trees. Some of the finest specimens of the Northern Spy apple, exhibited at the fairs, have been produced by grafts inserted into the terminal branches of old bearing trees. There is a theory held by some orchardists, that the further the junction of the graft with the stock is removed from the root, the better will be the fruit. This, however, is not well supported, and the circ.u.mstance, when observed, is probably dependent upon other causes.

In renewing an old orchard by grafting its head, it will not be a good plan to attempt the whole tree at once; the pruning would be too severe, and would be followed by a profusion of succulent shoots breaking out from the large branches, such as are called water-sprouts. Those who have practiced most, prefer at first, to remove about one-third of the limbs for grafting, and those should be selected at the top of the tree. The new growth thus has an open field for its development, and the lower limbs will be invigorated, while they tend also to preserve the equilibrium of the tree in a double sense, physically and physiologically. The next year another third of the limbs may be grafted, and the remainder the year following, as practiced by Mr. Geo. Olmstead, of Connecticut, who, on the sixth year from the first grafting, harvested 28- bushels of choice apples from a single tree that was 75 years old, and which before only produced inferior fruit. J.J. Thomas recommends, "to give a well-shaped head to such newly formed trees, and to prevent the branches from shooting upward in a close body near the centre of the tree; that the old horizontal boughs should be allowed to extend to a distance in each direction, while the upright ones should be lopped;"

see fig. 16. The same writer also advises, "instead of cutting off large branches and grafting them at once, it is better to prune the top in part, which will cause an emission of vigorous shoots. These are then budded, or grafted. * * * And as the grafts gradually extend by growth, the remainder of the top may, by successive excisions, be entirely removed."

[Ill.u.s.tration: Fig. 16.--RENEWAL OF THE TOP OF AN OLD TREE.]

GRAFTING IN THE NURSERY is either done at or near the collar of the stock, or it is performed in-doors upon the roots or sections of roots of young stocks. The latter may be first described, as it const.i.tutes the most extensive means of multiplying fruit trees. It is a sort of machinery, with division of labor, and appliances, that enable the operators to turn out immense numbers. Machinery has indeed been applied to the business; we have grafting apparatus to facilitate the work. The Minkler machine consists of a frame or gauge which regulates the angle of the slope, which is cut with a broad chisel that reduces the roots and scions to a condition for putting them together; by its use an immense number of grafts can be cut, and another hand binds them together with the waxed thread, without any tie. Mr. Robey's machine consists of a complicated shears to cut the slope and tongue at one operation, preparing the pieces for whip grafting. Mr. S.S. Jackson, of Cincinnati, has also invented an apparatus for this purpose, which proves to be very useful.

ROOT GRAFTING.--The methods of performing the operation vary somewhat, but all agree in the object to be attained: the co-aptation of the scion with a piece of root. Some grafters use only the upper portion of the root, thinking the original collar of the seedling stock the only point at which the most perfect and successful union between the aerial and terrestrial portions of trees should or can be effected--theoretically this may be very well, but the practice constantly pursued, in myriads of cases, abundantly proves that the grafting need not be restricted to this part, and that a perfect union may be effected at any point of the root, and that this may even be inverted. The very common practice has been to take two or more cuts from the root, when it is of sufficient size and length; and though some of our best propagators restrict themselves to two cuts from each, others, who have experimented carefully, insist that the third section will average as well as the others. A lot of trees, worked especially for a test in this matter, gave the following results.

In 1859 an average lot of roots and scions, about fifty in each lot, were treated as follows, White Pippin and Willow-leaf being used as scions:--

White Pippin--No. 1, being on the first cut of the root, had made a fair growth.

No. 2, being on the second cut, were quite as good or better.

No. 3, being on the third cut, were not quite so good as the others, the ground being partially shaded by a large tree.

Another, of Willow-leaf--No. 1, on the 3d cut of root, very good growth.

No. 2, on very slender roots, nearly as good.

No. 3, only 1 inch of root to 1 inch of scion; not so good growth nor so good a strike, but shaded by a tree.

No. 4, on 2d cut of root, not so good as the third.

No. 5, on average lot, not waxed, as good as any.

No. 6, roots worked upside-down, mostly failed.

D.O. Reeder exhibited some 2-year old apple trees, worked on the root inverted, they were of very good growth.

For root grafting, thrifty stocks are wanted of one or two years'

growth, the smoother and straighter the roots, the better. These should be taken up from the seed-bed in the fall, selected, tied in bundles, and stored in the cellar or cave, or buried in the soil where they shall be accessible at any time, and where they will be kept fresh and plump. The roots and scions having been prepared and under shelter, the work of grafting may proceed at any time during the winter. The stocks, if not clean, should be washed, and one hand trims off the side rootlets. The grafter cuts a hundred scions of the appropriate length, which he puts into a shallow box on the table; he takes up a stock, cuts the slope near the collar, and a dextrous hand will at the same time make the sloping cut to receive the first graft and also the tongue, if that style of grafting is to be done, as is usually practised. He then picks up a scion, from a lot which himself or another hand has already prepared with a slope and tongue, and adapts it to the root, the tongue keeping the two together; a portion of the root is then cut off with the graft, and the process is repeated upon the next section. Two or three or more grafts, are thus made from one seedling root; the length of the sections vary from two to four inches, according to the fancy of the operator, or of his employer. Some persons recommend a long scion with a short root, and others prefer to reverse those terms. The whole root graft should not be more than six or seven inches long.

When any given number of scions are fitted to the roots, a boy completes the process of grafting, by applying melted wax with a brush, in which case they are dropped into water to harden the wax, or they are wrapped with waxed strips of muslin or paper, or, better still, they are tied with waxed thread. No. 3 cotton yarn is drawn through a pan of melted wax, and wound upon a reel placed at the other side of the room, so that the wax may harden. This waxed thread is a very convenient tie; the graft being held in the left hand, the thread is wound about it two or three turns; as the wax causes the bandage to adhere to itself where it crosses, no knot is needed, and the thread is broken off with a quick jerk.

In splice grafting, whether performed with any of the machines, or if the slopes of root and scion be cut with the thin grafting knife, the tying must be done by the same hand that selects and places the scion upon the root. This does not admit of the same division of labor, and the fingers, becoming sticky from the wax, cannot be so nimble, and are unfit for cutting. When the lot is tied, they are set into the box, which should be inclined at an angle, and interspersed with earth or saw-dust; for transportation. Saw-dust, just as it comes from the mill, neither wet nor dry, is preferred by some as a packing material, and it has been found very efficacious, excluding and admitting the air just in the right proportions to prevent desiccation, and to promote the union, which very soon takes place between the graft and the root, if the boxes be stored in the cellar. In an ice-house root grafts have been kept in saw-dust more than a year, and then planted and grown successfully. The boxes should be deep enough to receive the whole graft--say from 10 to 12 inches--and then they can be packed upon one another without injuring the scions; these should be distinctly marked with the name and number, so as to be ready for planting out in the spring.

Much discussion has been had upon the merits and demerits, or disadvantages of root grafting, and much theoretical argument has been brought against the practice; but beautiful trees are thus made in immense numbers in the extensive nurseries of our country, and until better arguments can be produced against the practice, nurserymen will continue to graft on sections of root, such varieties, as are suitable for this procedure--especially apples, in a large proportion of the varieties cultivated, some pears, some peaches, grapes, and other fruits.

Root grafting is now of almost universal application with the apple.