Arum esculentum.—This root has not hitherto been considered of sufficient importance to demand particular care in its cultivation, except by those who are engaged in agricultural pursuits, and derive their subsistence from the production of the soil. But though the cultivation of the root is almost unknown to the higher classes in society, and little regarded by planters in the colonies, it is a most valuable article of consumption. Amongst the laboring population it is the principal dependence for a supply of food. Long droughts may disappoint the hopes of the yam crop, storms and blight may destroy the plantain walks, but neither dry or wet weather materially injure the coco; it will always make some return, and though it may not afford a plentiful crop, it will yield a sufficiency until a supply can be had from other sources. For this reason the laborer in the West Indies always takes care to put in a good plant of cocos to his provision ground as a stand by, and knowing their value, is perhaps the only person who bestows any degree of care or attention upon them. Previous to their emancipation, whole families of negroes lived upon the produce of one provision ground, and the coco formed the main article of their support. Where the soil is congenial to the white and black Bourbon coco, the labor of one industrious person once a fortnight will raise a supply sufficient for the consumption of a family of six or seven persons. The coco begins to bear after the first year, and with common care and cultivation the same plant ought to give annually two or three returns for several years. In Jamaica, a disease something similar to that affecting the potato, has been found injurious to the coco root. This disease, which has baffled all inquiry as to its origin, affects the plants in and after the second year of their being planted. The first indication of it is the change in the leaves, which gradually turn to a yellow hue, have a sickly appearance, and at length drop off at the surface of the earth. The stock or "coco head," as it is called, below ground, having become rotten, nothing but a soft pulpy mass remains. In some fields every third or fourth root is thus affected, in others much greater numbers are destroyed, so much so that the field requires to be almost entirely replanted, by which not only an expense is entailed, but a heavy loss sustained, from the field being thrown out of its regular bearing. The black coco seems to suffer less than the white.
Another species, the Taro (Arum Colocasia, Colocasia esculenta and macrorhizon), is an important esculent root in the Polynesian islands. In the dry method of culture practised on the mountains of Hawaii, the roots are protected by a covering of fern leaves. The cultivation of taro is hardly a process of multiplication, for the crown of the root is perpetually replanted. As the plant endures for a series of years, the tuberous roots serve at some of the rocky groups as a security against famine. It is also extensively cultivated in Madeira and Zanzibar, and has even withstood the climate of New Zealand. It is grown also in Egypt, Syria, and some of the adjacent countries, for its esculent roots. A species is cultivated in the Deccan, for the sake of the leaves, which form a substitute for spinach. Farina is obtained from the root of Arum Rumphii in Polynesia.
SWEET POTATOES.
The batatas, or camote of the Spanish colonies (Convolvulus batatas, Linn; Batatas edulis, of Choisy, and the Ipomæa Batatas of other botanists), belongs to a family of plants which has been split into several genera. It is a native of the East Indies, and of intertropical America, and was the "potato" of the old English writers in the early part of the fourteenth century. It was doubtless introduced into Carolina, Georgia, and Virginia soon after their settlement by the Europeans, being mentioned as one of the cultivated products of those colonies as early as the year 1648. It grows in excessive abundance throughout the Southern States of America, and as far north as New Jersey, and the southern part of Michigan. The varieties cultivated there are the purple, the red, the yellow, and the white, the former of which is confined to the South.
The amount of sweet potatoes exported from South Carolina in 1747-48, was 700 bushels; that of the common potato exported from the United States, 1820-21, 90,889,000 bushels; in 1830-31, 112,875,000 bushels; in 1840-41, 136,095,000 bushels; in 1850-51, 106,342,000 bushels.
The sweet potato is cultivated generally in all the intertropical regions, for the sake of its roots, and as a legume in temperate countries. In the Southern States of North America, the culture ceases in Carolina under latitude 36 degs.; in Portugal and Spain it reaches to latitude 40 and 42 deg.; and as a legume its cultivation is attempted to the vicinity of Paris. In India it is a very common crop; its tubers are very similar to the potato, but have a sweeter taste, whence the common name; but it must not be confounded with the topinambur (Helianthus tuberosus), a native of Brazil, which is less cultivated. The root contains much saccharine and amylaceous matter.
Several marked varieties of the sweet potato are raised in the Polynesian groups. In some islands it forms the principal object of cultivation.
It is grown in the Northern districts of New Zealand, at Zanzibar, Monomoisy, Bombay, and other parts of the East Indies. They are raised on the bare surface of the rock in some parts of the Hawaiian islands, and a sourish liquor is procured from them. It was early cultivated on the Western Coast of Africa, for the Portuguese Pilot (who set out on his voyages to the colony at St. Thomas, in the Gulf of Guinea) speaks of this plant, and states that it is called "batata" by the aboriginals of St. Domingo. They are abundant at Mocha and Muscat. Sweet potatoes form a principal and important crop in the Bermudas.
A valuable addition has lately been made to the votaries of the sweet potato in Alabama, supposed to be from Peru. A letter describing it says:—"It is altogether different and equally superior to any variety of this root hitherto known. It is productive, and attains a prodigious size, even upon the poorest sandy land, and the roots remain without change from the time of taking them out of the ground until the following May. The plant is singularly easy of cultivation, growing equally well from the slip or vine, the top or vine of the full-grown plant being remarkably small; the inside is as white as snow. It is dry and mealy, and the saccharine principle contained resembles in delicacy of flavor fine virgin honey."
There is in general a great error in cultivating this root, as most people still plant in the old way, two or three sets in the hole, which is a great deal too close.