Origin of Cultivated Plants. Alphonse de Candolle
Indians often establish their little plots of cultivation on points which would appear almost inaccessible to the great majority of our European farmers, we understand that when a traveller chances to visit one of these cultivated plots, long since abandoned, and finds there a plant of Solanum tuberosum which has accidentally persisted, he gathers it in the belief that it is really wild; but of this there is no proof.”
We come now to facts. These abound concerning the wild character of the plant in Chili.
In 1822, Alexander Caldcleugh,120 English consul, sent to the London Horticultural Society some tubers of the potato which he had found in the ravines round Valparaiso. He says that these tubers are small, sometimes red, sometimes yellowish, and rather bitter in taste.121 “I believe,” he adds, “that this plant exists over a great extent of the littoral, for it is found in the south of Chili, where the aborigines call it maglia.” This is probably a confusion with S. maglia of botanists; but the tubers of Valparaiso, planted in London, produced the true potato, as we see from a glance at Sabine’s coloured figure in the Transactions of the Horticultural Society. The cultivation of this plant was continued for some time, and Lindley certified anew, in 1847, its identity with the common potato.122 Here is the account of the Valparaiso plant, given by a traveller to Sir William Hooker.123 “I noticed the potato on the shore as far as fifteen leagues to the north of this town, and to the south, but I do not know how far it extends. It grows on cliffs and hills near the sea, and I do not remember to have seen it more than two or three leagues from the coast. Although it is found in mountainous places, far from cultivation, it does not exist in the immediate neighbourhood of the fields and gardens where it is planted, excepting when a stream crosses these enclosures and carries the tubers into uncultivated places.” The potato described by these two travellers had white flowers, as is seen in some cultivated European varieties, and like the plant formerly reared by de l’Ecluse. We may assume that this is the natural colour of the species, or at least one of the most common in its wild state.
Darwin, in his voyage in the Beagle, found the potato growing wild in great abundance on the sand of the sea-shore, in the archipelago of Southern Chili, and growing with a remarkable vigour, which may be attributed to the damp climate. The tallest plants attained to the height of four feet. The tubers were small as a rule, though one of them was two inches in diameter. They were watery, insipid, but with no bad taste when cooked. “The plant is undoubtedly wild,” says the author,124 “and its specific identity has been confirmed first by Henslow, and afterwards by Sir Joseph Hooker in his Flora Antarctica.125”
A specimen in the herbarium collected by Claude Gay, considered by Dunal to be Solanum tuberosum, bears this inscription: “From the centre of the Cordilleras of Talcagouay, and of Cauquenes, in places visited only by botanists and geologists.” The same author, Gay, in his Flora Chilena,126 insists upon the abundance of the wild potato in Chili, even among the Araucanians in the mountains of Malvarco, where, he says, the soldiers of Pincheira used to go and seek it for food. This evidence sufficiently proves its wild state in Chili, so that I may omit other less convincing testimony – for instance, that of Molina and Meyen, whose specimens from Chili have not been examined.
The climate of the coast of Chili is continued upon the heights as we follow the chain of the Andes, and the cultivation of the potato is of ancient date in the temperate regions of Peru, but the wild character of the species there is not so entirely proved as in the case of Chili.127 Pavon declared he found it on the coast at Chancay, and near Lima. The heat of these districts seems very great for a species which requires a temperate or even a rather cold climate. Moreover, the specimen in Boissier’s herbarium, gathered by Pavon, belongs, according to Dunal,128 to another species, to which he has given the name of S. immite. I have seen the authentic specimen, and have no doubt that it belongs to a species distinct from the S. tuberosum. Sir W. Hooker129 speaks of McLean’s specimen, gathered in the hills round Lima, without any information as to whether it was found wild. The specimens (more or less wild) which Matthews sent from Peru to Sir W. Hooker belong, according to Sir Joseph,130 to varieties which differ a little from the true potato. Mr. Hemsley,131 who has seen them recently in the herbarium at Kew, believes them to be “distinct forms, not more distinct, however, than certain varieties of the species.”
Weddell,132 whose caution in this matter we already know, expresses himself as follows: – “I have never found Solanum tuberosum in Peru under such circumstances as left no doubt that it was indigenous; and I even declare that I do not attach more belief to the wild nature of other plants found scattered on the Andes outside Chili, hitherto considered as indigenous.”
On the other hand. M. Ed. André133 collected with great care, in two elevated and wild districts of Columbia, and in another near Lima, specimens which he believed he might attribute to S. tuberosum. M. André has been kind enough to lend them to me. I have compared them attentively with the types of Dunal’s species in my herbarium and in that of M. Boissier. None of these Solanaceæ belong, in my opinion, to S. tuberosum, although that of La Union, near the river Cauca, comes nearer than the rest. None – and this is yet more certain – answers to S. immite of Dunal. They are nearer to S. columbianum of the same author than to S. tuberosum or S. immite. The specimen from Mount Quindio presents a singular characteristic – it has pointed ovoid berries.134
In Mexico the tuberous Solanums attributed to S. tuberosum, or, according to Hemsley,135 to allied forms, do not appear to be identical with the cultivated plant. They belong to S. Fendleri, which Dr. Asa Gray considered at first as a separate species, and afterwards136 as a variety of S. tuberosum or of S. verrucosum.
We may sum up as follows: —
1. The potato is wild in Chili, in a form which is still seen in our cultivated plants.
2. It is very doubtful whether its natural home extends to Peru and New Granada.
3. Its cultivation was diffused before the discovery of America from Chili to New Granada.
4. It was introduced, probably in the latter half of the sixteenth century, into that part of the United States now known as Virginia and North Carolina.
5. It was imported into Europe between 1580 and 1585, first by the Spaniards, and afterwards by the English, at the time of Raleigh’s voyages to Virginia.137
Batata, or Sweet Potato—Convolvulus batatas, Linnæus; Batatas edulis, Choisy.
The roots of this plant, swelled into tubers, resemble potatoes, whence it arose that sixteenth-century navigators applied the same name to these two very different species. The sweet potato belongs to the Convolvulus family, the potato to the Solanum family; the fleshy parts of the former are roots, those of the latter subterranean branches.138 The sweet potato is sugary as well as farinaceous. It is cultivated in all countries within or near the tropics, and perhaps more in the new than in the old world.139
Its origin is, according to a great number of authors, doubtful. Humboldt,140 Meyen,141 and Boissier
120
Sabine,
121
No importance should be attached to this flavour, nor to the watery quality of some of the tubers, since in hot countries, even in the south of Europe, the potato is often poor. The tubers, which are subterranean ramifications of the stem, are turned green by exposure to the light, and are rendered bitter.
122
123
Hooker,
124
125
Vol. i. part 2, p. 329.
126
Vol. v. p. 74.
127
Ruiz and Pavon,
128
Dunal,
129
Hooker,
130
Hooker,
131
132
Weddell,
133
André, in
134
The form of the berries in
135
Hemsley,
136
Asa Gray,
137
See, for the successive introduction into the different parts of Europe, Clos,
138
Turpin gives figures which clearly show these facts.
139
Dr. Sagot gives interesting details on the method of cultivation, the product, etc., in the
140
Humboldt,
141
Meyen,