Jerusalem Artichoke (Girasole). See [Artichoke].
Jessamine, Yellow. See [Gelsemium].
Jonquil. See [Narcissus].
Jubæa (Coquito Palm of Chili). Palmæ.
Propagation is effected by seeds.
Judas-tree. See [Cercis].
Juglans (Walnut and Butternut). Juglandeæ.
All the species are readily propagated by means of stratified nuts. Do not allow the nuts to become dry. Artificial cracking should not be done. In stiff soils the seedlings are apt to produce a long tap-root which renders transplanting difficult after the first year or two. The tap-root may be cut by a long knife while the tree is growing, or the young seedling may be transplanted. Particular varieties are perpetuated by grafting or budding with any of the common methods. In the north, they are sometimes worked indoors in pots. Common shield-budding works well, if the sap is flowing freely in the stock. Flute-budding is often employed. The improved native sorts are root-grafted in winter. Old trees can be top-grafted like apple-trees (see [p. 90]).
The “English” walnut (J. regia) is mostly grown direct from seed in this country, and the different varieties usually come true. In California, the native walnut (J. Californica) is often used as a stock for this species, and flute-budding on branches a half-inch or more in diameter is often practiced. “Twig-budding,” or the insertion of a short branchlet or bit of branch which is severed from the parent branch in the same manner as a shield bud, is sometimes employed.