Propagation by Means of Budding and Grafting Part 5
taken from The Nursery Manual (1934) by Liberty Hyde Bailey
Other uses of the cleft-graft.
Cleft-grafting is put to various other uses than the top-grafting of old trees. It is in common use on soft and fleshy stocks, as cactuses, and various fleshy roots. Fig. 184 shows a cleft-graft on cactus. The cion is held in place with a pin or cactus spine, and it is then bound with raffia or other cord. Waxing is not necessary.
A similar graft is often made on peony roots. The cleft in the thick root is cut with a knife, and the stock is bound up securely, usually with wire, as cord, unless waxed, rots off too quickly. Wax is not used, as the graft is buried to the top bud. The peony is grafted in summer.
Dahlias are often grafted in the same fashion, although some operators prefer, in such fleshy subjects, to cut out a section from the side of the stock to receive the cion, rather than to make a cleft, much as in the process of inlaying illustrated in Fig. 192. Hollyhocks, certain ipomeas, gloxinias and other thick-rooted plants may be similarly treated.
Miscellaneous forms of grafting
The ways of grafting are as many as the ways of whittling. Certain ones of them have gained considerable currency and may be set down here.
Splice-grafting. — The simplest form of grafting is that shown in Fig. 185, in which the two parts are simply cut across diagonally and laid together. The parts are held only by the string, which, together with the wax, is applied in the same way as on the whip-graft. Splice-grafting is frequently used with soft or tender wood that will not admit of splitting. It is adapted mostly to small shoots.
Saddle-grafting. — Saddle-grafting is a simple and useful method for the shoots of small growing plants. The stock is cut to a wedge-shape end by two cuts, and the cion is split and set astride the wedge (Fig. 186). The union is then tied and waxed in the same way as exposed whip-grafts. It is oftenest employed when a terminal bud is used, as the wood in such cions is usually too weak to work easily with a tongue.
Side-grafting. — There are various methods of inserting a cion into the side of a trunk or branch without cutting off the stock. One of the best methods is shown in Fig. 187. The example on the right shows the cion set into an oblique cut in the stock, and that on the left shows the lower part of a thin-bladed chisel, with a bent shank, that makes the incision. An ordinary chisel or a knife may be used, however. The incision should be about an inch deep. The cion is cut wedge-shape, as for cleft-grafting, and it is pressed into the incision until its cut surfaces are concealed in the stock. The wound is then tied, and, if it is above-ground in the open, it is waxed. The stock is headed back vigorously to aid in deflecting a part of the energy into the cion. This kind of grafting may be used to good advantage on rather small grape stocks, below the surface of the ground.
Shield-grafting. — A side-graft that is a combination of budding and grafting is shown in Fig. 188. The incision in the stock is exactly like that for shield-budding (Figs. 131, 137), but a cion, cut wedge-shape, is used in place of a bud. The graft is tied and waxed. This style of grafting is useful for many difficult subjects. It is admirably adapted to the mulberry, in which the operation should be performed just as the foliage is well started in the spring, with dormant cions. The stock is headed back a week or so after the cion is set, and again at intervals during the season. The cion often makes sufficient growth the first season to form a salable tree by fall. Purple and weeping beeches may be grafted in this way, except that the operation should be performed in late summer or fall, with freshly cut cions, much the same as for summer budding.
Bark-grafting. — A style of grafting suited to large trees is explained in Fig. 189. This is the bark-graft, sometimes unfortunately called crown-graft. The stock is not cleft, but the cions are pushed down between the bark and wood. The cions must be cut very thin, so that they will not break the bark on the stock (Fig. 190). It is cut to a shoulder on either side. Several cions can be placed in a single stub, and as no splitting is necessary, it is a useful method for very large limbs. It is specially useful in repairing trees when very large branches are broken off. The broken stub is sawn off smooth, and a dozen or more cions may be set around it. Only a few of them should be allowed to remain after the wound has been healed. Bark-grafting can be performed to advantage only when the bark peels readily. The cions should be held in place by a firm bandage, as seen in Fig. 189, and then wax should be applied as for cleft-grafting.
Bridge-grafting. — A special form of bark-grafting is sometimes employed for covering girdles about the base of an old tree, made by mice, gophers or rabbits. Inasmuch as it is surgery rather than propagation, a discussion of it is hardly in place in a nursery book, yet the reader is likely to look for it here.
The edges of the wound are trimmed, and cions are cut an inch or two longer than the width of the girdle, and they are sharpened at both ends. One end is inserted under the bark below the girdle and the other above it. The cions are placed close together entirely around the tree. The two ends are held firmly in place by tying, and the line of union is then waxed over. This operation is said to be necessary to keep up the connection between the root and the top, but this is in most cases an error, unless the girdle extends into the wood. A good dressing of wax or clay, held on with stout bandages, is often much better than the grafting. This method of grafting is sometimes, but erroneously, called inarching. A complete bark girdle made in spring or early summer will usually heal over readily if it is well bandaged; and in some cases even the bandage is not necessary. Several forms of bridge-grafting are practiced. Those described by Peck in Cornell Reading-Course Lesson 123 may be taken as examples.
Inlaying. — There are various kinds of grafting in which a piece of wood is removed from the stock and a cion is cut to fill the cavity. The following methods described by Lodeman for the grafting of grapes will serve as a type of the class: “The stock is cut off, as for cleft-grafting. In place of splitting the stub, one or two V-shaped grooves are made in it. These grooves are made by means of an instrument especially designed for the purpose. It is shown in Fig. 193. The tip cuts out the triangular part. In the blade itself is a part which is bent at the same angles as the parts forming the tip. This indented portion of the blade is used for cutting away the end of the cion, and with very little practice an almost perfect fit of the two parts can be made. The one or two cions are then placed upon the stock and are firmly tied there. The tying material should be of such a nature that it will decay before there is any danger of strangling the cions. Raffia does very well, as does also bast. No. 18 knitting cotton, soaked in boiling grafting wax, may be used with entire satisfaction. The ligatures should be made as tight as possible. Although this method of grafting is not so commonly used as others, it still possesses some decided advantages for grape vines. It is a much simpler and more satisfactory method than cleft-grafting in very curly wood. The tying is a slow process, and for straight-grained wood the cleft-graft is to be preferred. It is also open to the objection of requiring the shoots to be staked or tied to some support, for the wind is apt to break the point of union more easily than with other methods. A good union admits of a very strong growth, and if the above precautions are kept in mind the vines will equal those produced by the more common methods.”
Cutting-grafting. — Cuttage and graftage may be combined in various ways. Cuttings of plants that root with difficulty are sometimes grafted on those that root easily. A good example is in Fig. 159. When the plants are transplanted, the following autumn or spring, the nurse or stock may be removed, the cion having taken root. The connection may be made by means of a whip-graft, veneer-graft or other form.
Root-grafting, described on a previous page (see Figs, 138-143) is virtually a grafting of cuttings. In other cases, union with an uncongenial stock is facilitated by allowing the cion to project downwards beyond the point of union, and to stand in the soil or moss or dish of water. Fig. 194 is a good illustration of the practice. The cion extends into the earth nearly as far as the root itself. After union has taken place, the lower part of the cion is removed. This method can be used for magnolias, mulberries, birches and many other plants of which some kinds root with more or less difficulty. “Bottle-grafting,” described in most of the books, is essentially this method, modified by letting the end of the cion, or a piece of the bandage, drop into a bottle of water.
A modification of this style of grafting is the “cutting side-graft,” shown in Fig. 195. This is adapted to root-grafting, particularly of the grape. The stock is cut wedge-shape, and is inserted into an oblique incision in the cion.
Herbaceous-grafting. — In the preceding pages, the discussions have had to do with cions dormant or at least well hardened, and with stocks that contain more or less hard woody substance. But herbaceous shoots can be grafted with ease. All such plants as geraniums, begonias, coleuses, chrysanthemums and tomatoes, can be made to bear two or more varieties on the same individual. Almost any style of grafting may be employed, but the veneer-, cleft- and saddle-grafts are preferred. Shoots should be chosen for stocks that are rather firm, or in condition for making good cuttings. The cions should be in a similar condition, and they may be taken from the tips of branches or made of a section of a branch. The union should be bound snugly with raffia, and the plant set in a propagating-frame, where it must be kept close for a few days. It is not necessary, in most cases, to use wax, and on some tender stocks the wax is injurious. Moss may be bound about the graft, but unless the union is first thoroughly covered by the bandage, roots may start into the moss and the parts may fail to unite. The growing shoots of shrubs and trees can also be grafted but the operation is rarely employed. In various coniferous trees (as pines and spruces) the young shoots are sometimes cleft- or saddle-grafted in May, the parts being well bandaged with waxed muslin or raffia, and shaded with paper bags. The walnut and some other trees that do not work readily are sometimes treated in this manner.
Even leaves may be used as stocks or cions. Any succulent and permanent leaves, as those of the house-leeks, crassula, and the like, may have young shoots worked on them, and leaves used as cuttings can often be made to grow on other plants.
Fruit-grafting. — A little known species of herbaceous-grafting is the joining of parts of fruits. It is easily performed with fleshy fruits, as tomatoes, apples, squashes and cucumbers. When the fruit is half or more grown, one-half or a piece is cut away and a similar half from another fruit is applied. Better results follow if the severed side of the parent or stock fruit is hollowed out a little, so as to let the foreign piece set into the cavity. The edges of the epidermis of the stock are then tied up closely against the cion by means of bast or raffia. The two parts are securely tied together, but no wax is required. This operation succeeds best under glass, where conditions are uniform, and where winds do not move the fruits.
Seed-grafting. — An interesting kind of grafting has been described in France by Pieron, which consists in using a seed as a cion. This has been employed in the grape. A seed is dropped into a gimlet-hole near the base of the vine while the sap is rising in the spring. The seed germinates, and after a time the plantlet unites with the stock.
Inarching. — Inarching, or grafting by approach, is the process of grafting contiguous plants or branches while the parts are both attached to their own roots. When the parts have grown together, one of them is severed from its root.
The practice of inarching is explained in Fig. 196. In this case, the larger plant (on the left) is designed for the stock. When the smaller plant has united, it is cut off just below the union and it thenceforth grows on the other plant. Limbs of contiguous trees are sometimes grafted in this way. It is the process employed by nature in what is called natural grafting (Fig. 129). Grape-vines are often inarched.
A thrifty young branch of a fruit tree may be inarched into the stem of a fruit on the same tree, thus supplying the fruit with additional food and causing it to grow larger than it might if untreated.
To join the parts, it is necessary only to remove the barks between the stock and cion and then tie the two together snugly. The details are shown in Fig. 197. In M, a branch C is joined at O to the stock H. Other branches, like T, might be similarly treated. In N, the method of cutting the conjoined surfaces is explained at R. If outdoors, the junction should be waxed over; and it is then necessary, also, to secure the branches so that the wind cannot loosen them. The parts are sometimes joined by a tongue, after the manner of a whip-graft, but this is rarely necessary. Oranges and camellias were often propagated by inarching in the old practice, but this work is now much more easily accomplished by the veneer-graft.
Double-working. — Grafting on a grafted tree is known as double-grafting or double-working. It is employed for the purpose of growing a variety on an uncongenial root, or of securing a straight and vigorous stock for a weak and poor grower. The operation may be either grafting or budding. It is more commonly the latter.
Some sorts of pears do not unite well with the quince, and if it is desired to obtain dwarfs of these varieties, a variety that unites readily with the quince must first be put on it. The Angouleme takes well to the quince, and on Angouleme dwarfs the Seckel and some other varieties are often worked. In double-working dwarf pears, it is imperative that both unions be very close to the ground. The piece of interposed wood is not more than one or two inches in length. The second cion is usually set after the first one has grown one season, although both may be set at the same time.
Double-grafting for the purpose of securing a better growth is often practiced. The Canada Red apple, for example, is such a poor grower that it is often stem-worked or top-worked on the Northern Spy or some other strong stock. The Winter Nelis and the Josephine de Malines pears are often double-worked for the same reason. Fig. 198 shows the top of a double-worked tree. In this case, the body of the tree is two years old and is itself a graft or bud on a seedling root. The second variety is grafted to the point where it is desired to start the permanent top of the tree, by whip-grafting in this example. The figure on the left shows the two-year-old top growing from this cion. The length of the cion is comprised inside the dotted lines, and this region is enlarged in the figure on the right. The base of the cion was at T — below which is stock — and the top at N. The upper scar at N is the top of the cion itself, but the other scars show where superfluous twigs were removed after the cion had grown a year. This type of double-working of fruit-trees is to be recommended for weak or wayward growers.
Another practice now known as double-working is growing up in North American nurseries. It is the effort to produce named own-rooted stocks, thereby having a root of known hardiness and resistance to disease. By the use of the long cion and the short root, the cion becomes own-rooted in two years and this cion is then used for a stock as if it were a seedling. Success depends not alone on the methods of propagation but on the choice of a variety (for cions) that roots readily. Varieties of apples, for example, differ widely in their ability to form cion-roots. In this field undoubtedly lies opportunity for improvement in nursery propagation. It is the intention thereby to produce a stronger tree, to escape such diseases as collar-rot of the apple and to circumvent the root-louse (woolly aphis) to which many roots are particularly susceptible. The top of the tree is of known character and quality: the problem is to produce a root of known quality.
There are many recipes for waxes or mastics for protecting grafts and covering wounds. In this country, the resin and beeswax waxes are most used, although certain of the alcoholic waxes are popular in some regions. In Europe, many clay and pitch waxes are in common use. For most purposes, the wax No. 1, in the following list, is one of the best, especially for applying by the hand. The soft alcoholic waxes are liable to melt from exposed stubs in our hot summer suns; but they are useful for indoor work and for cool weather.
In making the resin and beeswax waxes, the materials are first broken up finely and melted together. When thoroughly melted, the liquid is poured into a pail or tub of cold water. It soon becomes hard enough to handle, and it is then pulled and worked until it becomes tough or “gets a grain,” at which stage it becomes the color of very light-colored manila paper. When wax is applied by hand, the hands must be well greased. Hard cake tallow is the best material for this purpose. In top-grafting large trees, it is well to carry a supply of tallow when waxing, by smearing the backs of the hands before entering the tree.
Common hard resin and beeswax waxes
(#1) Resin, 4 parts by weight; beeswax, 2 parts; tallow, 1 part. Turpentine, 2 to 4 ounces, is sometimes added.
(#2) Resin, 6 pounds; beeswax, 1 pound; linseed oil, 1 pint. Apply warm with a brush, one-eighth of an inch thick over all the joints.
(#3) Resin, 4 pounds; beeswax, 1 pound; and from half to a pint of raw linseed oil; melt all together gradually, and turn into water and pull. The linseed oil should be entirely free from cottonseed oil. A hard wax, for use in warm weather.
Waxes to be applied melted, from a grafting-pot (Peck)
(#4) A good melted wax may be made by the following formula:
- Resin (crushed) — 5 pounds
- Beeswax (finely cut) — 1 pound
- Powdered wood charcoal — 1/2 pound
- Raw linseed oil — 1/4 pint
Melt the resin and the beeswax together, add the charcoal, and stir the mixture briskly to prevent lumping. Add the linseed oil, and mix it thoroughly with the other ingredients. The wax is then ready for use. It is applied hot with a small brush. It does not crack badly, nor does it melt and run during hot weather.
(#5) Another formula for melted wax is as follows:
- Resin (crushed) — 6 pounds
- Beeswax (finely cut) — 1 pound
- Linseed oil — 1 pint
Melt the resin and the beeswax together. Stir in the linseed oil, and the wax is ready for use.
(#6) Liquid wax: Resin, 4 parts by weight; beeswax, 2 parts; mutton tallow, 1 part; alcohol, 1/2 or 5/8 part. Add the alcohol when the other ingredients are melted together and removed from the fire. A good soft wax.
(#7) Lefort’s liquid grafting wax, or alcoholic plastic: Best white resin, 1 pound; beef tallow, 1 ounce; remove from the fire and add 8 ounces of alcohol. Keep in closed bottles or cans.
Waxed string and bandage
(#8) Waxed string for root-grafting: Into a kettle of melted wax place balls of No. 18 knitting cotton. Turn the balls frequently, and in five minutes they will be thoroughly saturated, when they are dried and put away for future use. This material is strong enough, and at the same time breaks so easily as not to injure the hands. Any of the resin and beeswax waxes may be used. When the string is used, it should be warm enough to stick without tying.
(#9) Waxed cloth: Old calico or thin muslin is rolled on a stick and placed in melted wax. When saturated it is allowed to cool by being unrolled on a bench. It is then cut in strips to suit. Or the wax may be spread on the cloth with a brush.