Origin of Cultivated Plants / The International Scientific Series Volume XLVIII

by Alphonse de Candolle

These species of modern cultivation number sixty-one in the old world, marked C, and six in America, marked F; sixty-seven in all.

Classed according to their duration, they number thirty-seven per cent. annuals, seven to eight per cent. biennials, thirty-three per cent. herbaceous perennials, and twenty-two to twenty-three per cent. woody species.

The proportion of annuals or biennials is also here larger than in the whole number of plants, but it is not so large as among species of very ancient cultivation. The proportions of perennials and woody species are less than in the whole vegetable kingdom, but they are higher than among the species A, of very ancient cultivation.

The plants cultivated for less than two thousand years are chiefly artificial fodders, which the ancients scarcely knew; then bulbs, vegetables, medicinal plants (Cinchonas); plants with edible fruits, or nutritious seeds (buckwheats) or aromatic seeds (coffee).

Men have not discovered and cultivated within the last two thousand years a single species which can rival maize, rice, the sweet potato, the potato, the bread-fruit, the date, cereals, millets, sorghums, the banana, soy. These date from three, four, or five thousand years, perhaps even in some cases six thousand years. The species first cultivated during the Græco-Roman civilization and later nearly all answer to more varied or more refined needs. A great dispersion of the ancient species from one country to another took place, and at the same time a selection of the best varieties developed in each species. The introductions within the last two thousand years took place in a very irregular and intermittent manner. I cannot quote a single species cultivated for the first time after that date by the Chinese, the great cultivators of ancient times. The peoples of Southern and Western Asia innovated in a certain degree by cultivating the buckwheats, several cucurbitaceæ, a few alliums, etc. In Europe, the Romans and several peoples in the Middle Ages introduced the cultivation of a few vegetables and fruits, and that of several fodders. In Africa a few species were then first cultivated separately. After the voyages of Vasco di Gama and of Columbus a rapid diffusion took place of the species already cultivated in either hemisphere. These transports continued during three centuries without any introduction of new species into cultivation. In the two or three hundred years which preceded the discovery of America, and the two hundred which followed, the number of cultivated species remained almost stationary. The American strawberries, Diospyros virginiana, sea-kale, and Tetragonia expansa introduced in the eighteenth century, have but little importance. We must come to the middle of the present century to find new cultures of any value from the utilitarian point of view, such as Eucalyptus globulus of Australia and the Cinchonas of South America.

The mode of introduction of the latter species shows the great change which has taken place in the means of transport. Previously the cultivation of a plant began in the country where it existed, whereas the Australian Eucalyptus was first planted and sown in Algeria, and the Cinchonas of America in the south of Asia. Up to our own day botanical or private gardens had only diffused species already cultivated somewhere; now they introduce absolutely new cultures. The royal garden at Kew is distinguished in this respect, and other botanical gardens and acclimatization societies in England and elsewhere are making similar attempts. It is probable that tropical countries will greatly profit by this in the course of a century. Others will also find their advantage from the growing facility in the transport of commodities.

When a species has been once cultivated, it is rarely, perhaps never completely, abandoned. It continues to be here and there cultivated in backward countries, or those whose climate is especially favourable. I have passed over some of these species which are nearly abandoned, such as dyer’s woad (Isatis tinctoria), mallow (Malva sylvestris), a vegetable used by the Romans, and certain medicinal plants formerly much used, such as fennel, cummin, etc., but it is certain that they are still grown in some places.

The competition of species causes the cultivation of some to diminish, of others to increase; besides, vegetable dyes and medicinal plants are rivalled by the discoveries of chemists. Woad, madder, indigo, mint, and several simples must give way before the invasion of chemical products. It is possible that men may succeed in making oil, sugar, and flour, as honey, butter, and jellies are already made, without employing organic substances. Nothing, for instance, would more completely change agricultural conditions than the manufacture of flour from its known inorganic elements. In the actual state of science, there are still products which will be more and more required of the vegetable kingdom; these are textile substances, tan, indiarubber, gutta-percha, and certain spices. As the forests where these are found are gradually destroyed, and these substances are at the same time more in demand, there will be the greater inducement to cultivate certain species.

These usually belong to tropical countries. It is in these regions also, particularly in South America, that fruit trees will be more cultivated—those of the order Anonaceæ for instance, of which the natives and botanists already recognize the value. Probably the number of plants suitable for fodder, and of forest trees which can live in hot dry countries, will be increased. The additions will not be numerous in temperate climates, nor especially in cold regions.