Carlyle made fun, in his grim, sly way, of the countryman who "had no system"; but Hodge gets along rather better, in happy ignorance of what he would probably describe as his "innards," than a good many people whose vast knowledge of physiology only just stops short at ability to conduct a, learned post-mortem on themselves. Ignorance was just as blissful in the case of the old-style fruit grower, who knew nothing about the system of his trees, yet managed to get more fruit off them than the man who knew everything.
In these days we are not satisfied with knowing that a certain tree will bear Apples if we will only let it; we want to know what stock it is on, how it was worked, whether the man who budded or grafted it has passed an examination in pomology, and various other side items. Well, there is no harm in knowing a few facts about stocks, so long as we do not make the mistake of thinking that such information alone will fill the fruit room and reduce Covent Garden to astonished admiration: let us therefore glance at them for a few moments. A man has only to pass a probation in a fruit nursery to learn that there are scores of fruit stocks; and he has only to keep his eyes open to discover that half a dozen of them are vastly more important than all the rest. What, to begin with, is a "stock"? It is a species of the same genus as the fruit with which it is associated, of very poor fruiting qualities, yet possessing merits in the way of free, healthy, hardy growth, or of abundant rooting near the surface of the soil. Some people would do away with stocks, and grow the fruits from seed or cuttings on their own roots and stems. Other people admonish the earth for not being flat, and sow their seeds at the full of the moon. They are all harmless. Most of us make the best of the earth as it is, and adapt ourselves to the best systems of propagating fruit trees in the same philosophic spirit. Here are a few of the stocks used for fruit trees:-
Broad-leaved Paradise, narrow-leaved Paradise, Doucin, Nonsuch, Crab, and free (free stocks are seedlings of cultivated Apples, principally cider sorts).
Apricots, same as Peaches or Plums.
Mahaleb for dwarf trees, Gean and seedlings for standards.
Almond, Mussel, Myrobalan, St. Julien, and others.
Common Pear and Quince.
Brompton, Brussels, Black Damask, Mussel, seedling Plums, St. Julien, and others.
The most important of these are the broad-leaved Paradise and the Crab (Apples); the Gean and the Mahaleb (Cherries); the Mussel and St. Julien (Peaches and Nectarines); the Pear and Quince (Pears); the Brompton and Mussel (Plums). With respect to Pears, however, there are some varieties which will not take to any stock, and have to be worked on a foster variety which is already established on the stock before they will make a good union. I have found Beurre d'Amanlis to be the most useful of these foster Pears; Ollivier de Serres is also serviceable, and there are many others.
I do not think that the person who grows a small collection of fruit for private purposes need trouble much about the stock question. He is not likely to gain much by it, and he may easily waste both time and money. Trade and market growers should, however, study the subject. To them Fig. 22, can hardly fail to be helpful. It shows that "free" and dwarfing stocks are essentially different. The former, which is raised from seed, has a tap root, which must be removed before the stock is worked; the latter, which is raised from a layer, has no tap root. Observe here an important point. In root pruning trees on seedling stocks it is the central, deep-striking roots which require severing, not the smaller horizontal ones (see the dotted diagonal lines in A, and the tap a; if the roots outside the lines were cut and the tap left unshortened, harm would be done). In root pruning trees on layered stocks the rambling side roots may be shortened, and the central roots left alone. This point does not receive due weight from cultivators, who rarely think of the stock when root pruning. The illustrations make clear the natural difference between Crab (or free) and Paradise stocks. The one has a strong, spreading root system, which must be checked by transplanting and cutting the tap root if early fruitfulness is to be had. The other has a close, fibrous root system, more conducive to early productiveness.