Botany: The Science of Plant Life

by Norman Taylor

THE BANANA

Among the largest herbs in the world are the ordinary banana plants, now cultivated throughout the tropical regions, but originally native in the Malay Archipelago. From there it spread into India, and the early Greeks, Latins, and Arabs considered it a remarkable fruit of some Indian tree. It is actually a giant herb with a tremendous fleshy stem, formed mostly of the tightly clasping leaf bases, the blade of which is frequently ten to twelve feet long. In nature the blade splits into many segments due to tearing by the wind, a process that the plant not only tolerates but aids. The leaf has a thinner texture between its principal lateral veins, and along these weaker parts the leaf tears so that normal plants are usually almost in ribbons. The leaf expanse, without this relief, is so great that tropical storms would doubtless destroy the plant.

Many wild species of the banana are still found in tropical Old World countries, the genus Musa to which the banana belongs having over sixty-five species. There are at least three well-marked types of banana used to-day, two of them, our common yellow one and a smaller red sort being fruits of almost universal use. The remaining type is usually larger than the kinds sent to northern markets, is picked and used while still green and is always cooked before using, usually boiled as a vegetable. In this form it is known as the plantain, and is a good substitute for the potato in regions where the latter cannot be grown. Plantains are used on a large scale in all tropical countries, much more so than the yellow and red bananas which are familiar enough in northern markets. These are too sweet to be used as a staple diet, and the plantain is practically the only such diet which millions of the poorer people in the tropics ever get. There is almost no native hut but has its plantain field.

The flowers of the banana plants, all of which appear to be derived from the single species Musa sapientum or possibly also from Musa paradisiaca, are borne in a large terminal cluster which ultimately develops into the “hand” of bananas familiar in the fruit shops. The plant then dies down and a new one develops from a shoot at the base of the old stem. For countless ages this has been the only method of reproduction, and usually the banana produces no seeds. The plant is easily grown in greenhouses, one in the conservatory of the Brooklyn Botanic Garden producing 214 pounds in a single cluster consisting of 300 bananas.

POTATO

Sir Walter Raleigh is usually credited with the introduction of the potato into Europe, although it appears as though the Spaniards were the first to bring the plant from America. It was brought to Ireland in 1585 or 1586 and from its wide use there became known as the Irish potato. Its native home is in southern South America, and although Columbus did not mention it after his first and second voyages, subsequent Spanish adventurers found natives on the mainland making extensive use of it. There are now several wild relatives of it in South America, but their tubers are not so large as those of Solanum tuberosum from which all the different varieties of potato have been derived. The plant is too well known to need description here, but its edible tuber, actually a stem organ, is often wrongly called a root. Figure 8 shows the tubers and true roots of the plant.

The sweet potato, which in early writings was often confused with Solanum tuberosum, is a very different plant. Its edible portion is the root of a vine very like our common morning-glory or convolvulus, and its Latin name is Ipomœa batatas. The specific name is taken from a native American word, which due to early confusion was corrupted into potato, and applied to the “Irish” potato. No one certainly knows where the sweet potato is native, but probably in tropical America. It belongs to a section of the genus Ipomœa, all the other species of which are American, and before Columbus and his followers its cultivation was unknown in the Old World. It was very soon carried by the Portuguese to Japan and other parts of the Old World, and for a time it was thought to be native there. America, however, is in all probability its ancient home, although no really wild plant has ever been found there or anywhere else. Its cultivation from very early times in America is indicated, and Columbus upon his return from the New World presented sweet potatoes to Queen Isabella.

COCONUT

It has been said many times that there are more uses for this plant than there are days in a year. Wood, thatch, rope, matting, an intoxicating beverage, and scores of other things are derived from different parts of this palm, but it is as a food and beverage that its chief value lies. The coconut palm is a tall tree with a dense crown of feathery but stout leaves and inhabits all parts of the tropics. It is found apparently wild along sandy shores, but its ancient home, while still unknown, is probably America. Each year the tree bears from ten to twenty fruits which are at first covered with a green and very tough fibrous husk, inside which is the seed, the coconut of commerce. In the early stages of the fruit the white meat is preceded in large part by a delicious milky liquid much used by the natives, but only rarely found in any quantity in the coconuts shipped to our markets. The meat is highly nutritious and is used on a great scale as food by millions of tropical peoples. Within the last few years a method of taking out the meat of the coconut and shipping it in a state of arrested fermentation to the north has been discovered. This product, known as copra, is produced in enormous quantities, both in the Old and the New World, particularly in India and the Philippines. From this copra a palm oil is refined, which is the chief source of the nut butter now so widely sold. Some idea of the extent of the cultivation of coconuts may be gleaned from the fact that in India and the Philippines the trees are counted by the hundreds of millions. The oil from the nuts is also largely used in cookery, in making candles, for burning in lamps, and in making certain kinds of perfume. The tree belongs to the Palmaceæ, a monocotyledonous family of plants of great commercial importance. It is known as Cocos nucifera, and the genus has over a hundred species, all of tropical American origin. Whether Cocos nucifera is American or not is still a disputed point. From the fact that it will float in sea water without injury to the seed it has been supposed that it was carried great distances by currents. It is found both wild and cultivated throughout the tropical world, and its use appears to have been known to the Asiatics probably four thousand years ago. The curious fact remains that it is the only palm that, in its wild state, is known both in the Old and New World, all others being peculiar to one hemisphere or the other. Perhaps its capacity for floating in the sea without injury may explain what is otherwise still a good deal of a mystery.

There are many other foods derived from plants, besides all the fruits and vegetables too numerous to be noted in detail here. One fact of significance seems to stand out from a study of the uses of plants by man. There are three distinct regions from which the great bulk of our food and many other useful plants have apparently come. One is the area of which Indo-China is approximately the center, and which is the ancestral home of rice, the banana, tea, sugar cane, and many other valuable plants. Somewhere in this southeastern corner of Asia there must have been a highly developed agriculture which rescued these plants from the wild, and from which they have spread throughout the world. The second region, somewhere near Mesopotamia, appears to be the cradle of wheat and a few other useful plants. And the third region is the western part of America from southern Mexico to northern Chile, where corn, tobacco, the pineapple, sweet potato, potato, the red pepper, and the tomato were all discovered with the discovery of this continent.