STOCKS, in Horticulture, are young trees which are designed for the reception of the grafts or buds from other trees. The process by which a part of one tree is transferred to another is called grafting or budding [OnArrtso], and the object attained by it in gardening ie the securing the continuance and multiplication of an individual plant that may possess peculiarities deemed worthy of preservation. It is by this process that the great number of varieties of cultivated fruits are preserved with remarkable integrity, and by which a constant. improvement may be ensured.
Stocks are for practical purposes divided into three kinds : crab stocks, free stocks, and dwarf stocks. Crab stocks are those which are grown from the seeds of wild and ungrafted trees, as the cherry, plum, apple, &c. These stocks are commonly used where a large and hardy growth is desirable. In the selection of wild stocks, those which grow cleanest, and are freest from irregularities of the stem and defects in the bark, should be chosen. Free stocks are those which are raised from the seeds or layers of fruit and orchard trees which have been grafted. These stocks are found desirable when the object of grafting is to obtain choice varieties of apples, peaches, nectarines, apricots, or plums. Dwarf stocks are those which are raised from low-growlng shrubby trees. They are used in the grafting of low-standards for small gardens, also for wall-trees,lind espaliers.
Stocks are raised in nurseries from seeds, suckers, layers, and cuttings. When raised from seeds, they should be sown in the autumn, in beds of common light earth : all lateral branches should be cut off as they grow up; and, according to circumstances, they will be fit for grafting in one, two, or three years. Stocks may be used when they have attained the size of a goose-quill, up to that of a man's finger. When stocks are wanted expeditiously, they may be produced from suckers taken up and planted in the autumn, when they will be ready for use the following July or August. They are not often raised
from layers and cuttings.
In the selection of stocks, not only is care required that they be of the same kind as the graft or scion, but that there is a proper relation between the rapidity of their growth according to the objects wished to be attained. When the growth of the scion is more rapid than that of the stock, it will sometimes die. This is the case with pe.sch.trees budded on plum-stocks and pears on the hawthorn. At the mine time, when trees are naturally too luxuriant in leaves and branches, they may be dwarfed in their growth and made fruitful by placing a scion from them on a stock that grows slower than themselves. In this way apples may be dwarfed by being grown on paradise, pear, or quince stocks.
It is frequently desirable to select those stocks which are hardier than the scion, for the purpose of ensuring the growth of the latter. Not that the stock has any power of communicating hardiness to the scion ; but those stocks that are accustomed to colder latitudes will supply a sufficient quantity of sap, and be able to resist the influence of a decrease of bottom heat. The kind of soil in which a stock grows has also much to do with its being adapted for the growth of certain scions. Thus the crab has been found best for the apple, the wild per for the cultivated pear, the almond for the plum, and the mahaleb for the cherry, on chalky soils. But the stock also has the power of deteriorating the fruit; the austere plum and the crab will not im prove the peach or the apple of the scion which may be grafted on them. Some gardeners therefore recommend stocks of what they term an ennobling character; that is, of a species as good as that of the scions they are to bear. Apricots, currants, and gooseherries are stated to have been greatly improved by this process.