Page:The New International Encyclopædia 1st ed. v. 09.djvu/125

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GRAFSTROM. 103 GRAFTING. His poems won him the special prize from the Swedish Academy in 1817. Many of his songs are very popular, and have been set to music by Kordblom. They wci-e originally publislied in the journals of the day, but have been collected under the title Samlade sKaldcslyckeii (1864). GRAFTING (fvom OF. grajje, a sort of pen- cil; slip for grafting resembling a pointed pencil in shape, from Lat. Vap'""'". *!'"'" *^^- r/'ai*"'"'. qrapheion. pencil, graving chisel, from jpafl"', nraphehi, to write) . The operation by which the cut surfaces of two branches or roots, either from two different plants or from the same plant, are caused to grow together. The portion used to perpetuate its kind is usually of the present or past season's growtli, and is called a scion The portion into which the scion is inserted is termed the stock, and usually carries roots, or is a part of a root, although in rare cases unrooted cuttings are used as stocks, the art of grafting has been practiced from pre- historic times. Its originator is unknora. the process depends entirely upon the ability ot plants to heal wounds. When two wounded (cut) surfaces are so adjusted that the cambium layer of one coincides at any point with the cambium layer of the other, union by granula- tion of the two surfaces may take place, connec- tion between the conduction vessels of stock and scion becomes established (see Conduction) .and new growth begins. The great value of grafting consists in the ease and comparative certainty with which cultural varieties can be increased without serious loss of type characters. ^ ere all forms of the art of grafting to be taken from the horticulturist, commercial tree-fruit growing in its high state of perfection would decay with the orchards existing at the time. WHIP GRAFTING. 1. Stock. 2. Scion. 3. Stock aud scion acfjusted.

horticultural varieties or sorts of fruits 

that belong to the pome, the drupe, or the citrous classes are now multiplied almost wholly by graftage which includes both budding and graft- in" This art and that of cuttage are the foun- dations of the entire superstructure of tree-fruit growing. The progress in plant-breeding ami the great rapidity with which new sorts are now disseminated has been largely, and with tree- fruits almost wholly, attained by the aid of graftage and cuttage. Graftage permits the originator of a new sort of apples, for instance, to disseminate the variety with the minimum of risk that it will depart from the type, thus avoiding the dilliculty, nay, almost impossibility, of reproducing the type from seed. The method of reproducing the sort does not enter as a factor in his efforts to secure a desired variation. Be- sides the reproduction true to type, grafting is used to hasten or to increase fruitfulness; to replace undesirable varieties by desirable ones; to reduce the size of plants by working them on a smaller growing species of stock, e.g. the pear upon the quince; to overcome the effects of injuries, as in the case of tiiink-girdlmg by mice or rabbits. The wood for scions, like that for hard-wood cuttings, must be taken while in a resting condition. The time usually considered best is after the leaves have fallen, but before severe freezing begins in early winter. The scions are then tied in bunches and buried in moist soil or sand, where they will not freeze, but will be kept cold enough ' to prevent swelling of the buds. Good results often follow the cutting of scions in the spring, just before or at the time the grafting is to be done. The two most popular methods of grafting are the whip and the cleft. For irhip grafting of roots the scions should be cut in the autumn, • because spring cutting allows insufficient time for the union of the two surfaces before growth starts. This style of grafting is the one most extensively used in root grafting. It is well suited to "young plants or parts of plants used as stock, and to indoor work during the com- parative leisure of winter. Both the stock and the scion are cut diagonally and smoothly with a sharp knife, leaving about an inch of cut sur- face across which, in both stock and scion, a slit is mad" parallel with the direction of growth, as shown in Figs. 1 and 2. The one object to secure is the juxtaposition of the cambium layers of stock and scion. This may be accomplished by having the bark of the stock coincide with or cross the bark of the scion at a slight angle. Aft«r the scion and stock have been joined as in Fig. 3, they should be wrapped with several turns of cotton soaked in grafting wax, in order that the parts may be held firmly together. The root or stock may be left any convenient length, from two and a half to six inches, and the scion cut according- ly. This cutting, however, is usually done before the joining of the two pieces. In general, the shorter the root, the longer the scion, and vice versa. The practices of the more rigorous cli- mates tend to short-piece roots and long scions. The resulting trees, being set deeply, soon send out roots from the scion, and become 'own root- ed ' in which case they are believed to be superior to' trees that obtain their nourishmeut solely through the foster roots of a stock. No ex- periments have been conducted to settle this mat- ter, but common experience is more in favor of the short root deeply set than the reverse At planting time, root grafts thus made should be covered.' only the topmost bud of the scion being left above the soil. If the graft is to be ex-