When worked at the top of a stem formed of the stock, the growth from the graft or bud must be pruned in a similar way.
This species is frequently used as a stock on which to graft other Cacti.
Grafting, however, has not been found to answer the purpose, since the stock and the graft have been found to retain their respective alkaloids in the natural proportion just as if growing separately.
Some of the American varieties have been introduced into France and other countries infested with Phylloxera, to serve as stocks on which to graft the better kinds of European vines, because their roots, though perhaps equally subject to the attacks of the insects, do not suffer so much injury from them as the European species.
Other race mixtures consist of the zambos (the African-Indian cross), an Asiatic graft upon these various crosses, and an extremely confusing intermixture of the various crosses, for which the Spanish races have descriptive appellations.