FOR perhaps the largest number of readers the chief value of plants is what they furnish in the way of food, clothing, fuel, and so forth, and from this standpoint alone the study of them is more than worth while. It is unnecessary here to enumerate all the thousand and one things that we get from plants, and no attempt will be made to do so in the following pages. But certain plants like wheat, corn, cotton, jute, rubber producers, and tobacco have so shaped the life of the people, so absolutely dictated the development of whole regions of the earth’s surface that their stories are part of the history of mankind. What our cotton fields of the South, the wheat and corn fields of the Middle West, the jute in India, and the coconut palm and sugar cane in the tropics have done to dictate the economic destiny of those regions is common knowledge. Hundreds of less important plants throughout the world contribute their quota to the huge debt that man owes to the plant world. Probably no other feature of plant life offers such attractions as the study of man’s uses of plants, which is known as Economic Botany, and for which our Government maintains a large staff of experts. Some of the publications of this bureau are textbooks of the greatest value to those who grow or import plants or their products. What that amounts to in the aggregate 1. FoodsThose early ancestors of ours that roamed over northern and central Europe between the periods of ice invasion, which at times made all that country uninhabitable, tell us by the relics of them found in caves that agriculture was then unknown. Living mostly by the chase and on a few wild fruits picked from the forest these half-wild and savage people wandered wherever game was plentiful and the continental glacier would permit. But there came a day when one of these races began the cultivation of some of the wild plants about them and with that day dawned the real beginning of man’s use of plants. And with that day also these simplest of our ancestors stopped their wanderings in large part and became farmers, albeit very crude ones, as their primitive stone implements show. They did not give up the chase, but their collection into more or less permanent camps or villages began with their cultivation of plants. Just when this happened no one can say, but most estimates of the time since the last ice age indicate that it could not have been much less than forty thousand years ago. And considerably before this, and long before the use of metals by man, we find these stone implements of agriculture and the probable beginnings of that great reliance upon plant life which the modern world has carried to such tremendous lengths. Unfortunately we do not know what plants these “Men of the Old Stone Age” grew in their primitive gardens, and it is thousands of years after this, and after man’s discovery of the use of metals, that we WHEATThe discovery of the grain of wheat in the remains of the lake dwellers tells us some things about men’s travels even in those early days, for wheat is not a wild plant there and must have come to central Europe from a great distance. Researches upon the home and antiquity of wheat are not very definite, but its occurrence as a wild plant somewhere in Mesopotamia or the vicinity appears to be indicated. The Chinese grew it 2700 B.C. and the earliest Egyptians spoke of its origin with them as due to mythical personages such as Isis, Ceres, or Triptolemus. From its ancient and perhaps rather restricted home it has gone throughout the temperate parts of the earth and now forms perhaps It were perhaps well to note here that popular stories about the germination of grains of wheat taken from Egyptian mummies are not true. Wheat and even corn are sometimes given to travelers, and it is taken from these ancient Egyptian tombs. But it was not put there by the early Egyptians, as the presence of corn proves only too well. For this cereal is an American plant unknown before Columbus and 1492. Arabs and others have recently inserted various seeds in these mummies, some of which undoubtedly have germinated—hence the fable. The early Egyptians did put seeds in their mummy cases, but none have ever germinated. INDIAN CORN OR MAIZEThe grass family furnishes this second most important cereal to all Americans and Europeans, although among inhabitants of tropical regions rice is perhaps more important than either wheat or corn. With the discovery of America the early travelers found the North American Indians, the Field corn of several different sorts, pop corn, and sweet corn were all developed by the Indians from RICEBoth wheat and corn are grasses that are cultivated in ordinary farm soils, but rice is derived from a grass that is nearly always grown for part of its life in water. It is taller than wheat, but not so tall as corn, and its wild home is in the tropical parts of southeastern Asia. It is still grown there in greatest quantity, and in the Philippines, while only a small part of the world’s supply comes from the New World. There are perhaps more people that rely upon rice for food than upon wheat and corn combined. It still is the principal article of diet of the inhabitants of China, Japan, India, and dozens of smaller Old World regions, while its use as a vegetable in tropical America is practically universal. A considerable part of the starch manufactured in Europe still comes from rice, and in India the intoxicating beverage arrack is made from it. The Japanese sakÉ, a sweetish intoxicating liquor, is also made from rice. Notwithstanding its wide use it is not as nutritious as wheat or corn, being much lower in proteins than either of them. More than 2800 years before Christ the Chinese cultivated rice, for at that time one of the emperors instituted a ceremony in which the grain plays the chief part. It has been grown on land useful to almost no other crops as it is usually subject to inundations. Some varieties, however, have been SUGARIn the chapter on what plants do with the material they take from the air and soil we found that sugar was one of the first fruits of that process. In at least two plants the overproduction of sugar is on such a great scale that our chief supplies of this substance now come from these two plants—the sugar cane, which is a tall grass, and the sugar beet. Hundreds of other plants produce surplus sugar, but for commercial purposes these two, and the sap of the sugar maple (Acer saccharum), are our chief sources of supply. Cane sugar is an Old World grass known as Saccharum officinarum, frequently growing twelve feet high, and with a solid woody stem, quite unlike our ordinary grasses. It looks not unlike corn on a stout stem, and it is the stem which is cut and from which the sweet juice is pressed out between great rollers. The pressed-out juice goes through various Our consumption of sugar is now on such a scale that we scarcely realize that before the days of Shakespeare it was very scarce and expensive. Even as recently as 1840 it regularly sold in England for forty-eight shillings per hundred pounds, wholesale. At that time the total consumption in the world was only slightly over a million tons, while to-day it is over fifteen times that amount. The plant is native in tropical Asia, but just where is not known, nor are wild plants found in any quantity. It has been much modified by long cultivation, and has been reproduced by root-stocks for so long a period that it is rare for the plant to bear flower and seed. It has been known in India since before the Christian era, and was taken from there to China about 200 B. C. Neither the Greeks nor Romans knew much about it, nor do the Hebrew writings mention it. Somewhere in the Middle Ages the Arabs brought it into Egypt, Sicily, and Spain. Not until the discovery of the New World was it cultivated on any considerable scale, when the climate of Santo Domingo and Cuba and the African slaves imported to those islands afforded conditions that resulted in Cuba at least being one of the world’s chief sugar-producing countries. Sugar cane is now grown all over the earth in regions with a hot, moist climate, India and neighboring countries producing over half the world’s supply. Practically all the sugar produced in India is used there, however, so that the American tropics furnish to Europe and America about one-third of the world’s total consumption of cane sugar. In 1840 under fifty thousand tons of beet sugar were produced, while in 1900 more sugar from this plant was made than from sugar cane. Considerably more than half this beet sugar was grown in three countries, Russia, Austria, and Germany, which explains what the great war has done to the sugar market. The plant from which beet sugar is derived is botanically the same as the common garden beet, Beta vulgaris, which is wild on sandy beaches along the Mediterranean and Caspian seas, and perhaps in India. Much cultivation has made this slender-rooted plant into the large-rooted vegetable we now have and its sugar content was much increased by Vilmorin, a French horticulturist. Many garden varieties are known, and some of these are grown in the United States, where beet sugar is produced, although in 1910 less than half a million tons were made here as against over four million tons in Europe. While the beet as a vegetable was known perhaps a century or two before the time of Christ, it was not until 1760 that its sugar content was understood, and it was nearly eighty years later before beet sugar became commercially important. Its cultivation in England on any considerable scale did not begin before the beginning of the present century. THE BANANAAmong 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 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 POTATOSir 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 Ipomoea batatas. The specific name is taken from a native American word, which due to early confusion was corrupted COCONUTIt 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 There are many other foods derived from plants, besides all the fruits and vegetables too numerous Alphonse de Candolle, from whose studies much of our information on the origin of cultivated plants is derived, once prepared a list of our common vegetables showing their ancient homes, their wild ancestors, and the length of time during which they have been in cultivation. With some recent additions and corrections by Dr. Orland E. White of the Brooklyn Botanic Garden, the list is printed below: The letters indicate the probable length of cultivation. (a) A species cultivated for more than 4,000 years. (b) A species cultivated for more than 2,000 years. (c) A species cultivated for less than 2,000 years. (d) A species cultivated very anciently in America. (e) A species cultivated in America before 1492 without giving evidence of great antiquity of culture. (f) A species or subspecies of very recent domestication.
The following list of the common fruits also gives their native country, period of cultivation, and some additional notes about them. Those marked with a star were found in the markets of New York City by Dr. White, who also revised this list. The letters for the dates are the same as in the list of vegetables:
2. BeveragesThe operation of the Eighteenth Amendment to our Constitution will stop the manufacture in this country of the chief beverages that were made here from plants. All wines and brandies were from the juice of the grape, whiskey from rye and some other cereals, and beer from hops and barley. Our three remaining beverages of practically universal use are none of them produced in the United States, with the exception of a little tea grown in a more or less experimental way. TEAIt is related in an old legend that a priest going from India into China in 519 A.D. who desired to watch and pray fell asleep instead. In a fit of anger or remorse he cut off his eyelids which were changed into the tea shrub, the leaves of which are said to prevent sleep. Unfortunately for the story tea was known in China more than three thousand years before the date of that legend, and it is very doubtful if it was ever brought from India to China. The wild home of the tea is apparently in the mountainous regions between China and India, but the plant The plant is mostly a shrub or occasionally a small tree, with white fragrant flowers and evergreen oval-pointed leaves. All the different kinds of tea are derived from the single species Camellia Thea, the differences in color and flavor being due to processes of culture or curing of the leaves. While the use of tea has been known to the Chinese for over four thousand years, its introduction into Europe dates from the days of the Dutch East India Company, who brought some to Holland about 1600, and by the English East India Company, who sent some from China to England in 1669. It fetched at that time 60 shillings per pound for the common black kinds and as much as £5 to £10 per pound for the finer kinds. It was almost fifty years, or about 1715, before the price fell to 15 shillings per The cultivation of tea is restricted to those regions where there is a large and frequent rainfall as well as a high temperature. It will not grow in marshy places such as rice prefers, but needs light, well-drained soils. The plant is propagated only from seeds which are sown in nurseries, and the young plants set out in the tea fields about four and a half feet apart each way. In two years they are bushes from four to six feet tall when they are cut back to a foot high. The increased vigor of the bush from this severe cutting back results in a dense bush, from which leaves are plucked from the third year in small quantity. Not until after the sixth or seventh year is there a normal yield, which in an average year would be from four to five ounces of finished tea. A poor yield of leaves would average about 400 pounds of tea per acre, good yields going as high as a thousand pounds or even more than that. The tea fields must be kept free of weeds, a tremendous task in a moist tropical region, which demands cultivation about nine times a year. The expense of properly setting out and maintaining a tea plantation is therefore considerable. The plucking of tea leaves is a fine art beginning with the starting of new growth and continuing every few days until growth stops. In certain regions growth is practically continuous and plucking The thing for which we drink tea is an alkaloid in its leaves that is pleasant to the taste and refreshing to the senses. It is released in boiling water in a very few minutes, but if tea is allowed to stay in water longer than this, tannic acid is also released. This is a substance found in the bark of certain trees and is used in tanning leather. As 10 per cent of the leaf of tea consists of this substance it may readily be seen how easily improper methods of making tea will render it not a refreshing and delightful beverage but an actual poison to the digestive tract. COFFEELike tea and chocolate, coffee also comes from a plant that can only be grown in the tropics. Its original home was in or near Arabia and its botanical name is Coffea arabica. There are, however, other species of the genus that produce coffee, but Coffea arabica is still its chief source. The plant is now grown throughout the tropical world, but it does not thrive so well along the coast as it does at elevations of a thousand feet or so, where, in America at least, the best coffee is produced. The plant is a shrub or small tree, usually not over 12 to 15 feet tall, with opposite leaves and small tubular flowers, followed by a bright red berry, which contains the coffee “beans.” The flowers and berries are in small clusters in the axils of the leaves. Its use among the natives appears to date from time immemorial, but the Crusaders did not know it, nor was it introduced into Europe much before 1670. Its annual consumption is now well over two billion pounds, nearly half of which is used in this country. We use over ten pounds a year for each man, woman and child in the country, or nearly ten times the per capita consumption in England. Brazil produces over half the world’s total supply and consequently controls the coffee markets of the world. The plant was first brought into South America by the Dutch, who in 1718 brought it to Surinam. From there it The coffee berries are collected once a year and spread out to dry, after which the two seeds are taken out. This is the simple method of all the smaller plantation owners, but a modern Brazilian coffee plantation follows a very different procedure. The berries are put in tanks of water, or even conveyed by water flues from the fields, and allowed to sink, which all mature berries will do. They are then subjected to a pulping machine which after another water bath frees the beans from the pulp. The former are still covered by a parchmentlike skin which, after drying of the beans, is removed by rolling machines. The coffee is then ready for export, but not for use until it is roasted. This is a delicate operation not understood except by experts, and should not be done until just before the coffee is ready to be used. The average yield per plant is not over two pounds of finished coffee a year, but larger yields from specially rich soils are known. The plant is rather wide-spreading and not over five or six hundred specimens to the acre can be grown. The so-called Mocha coffee is obtained in Arabia, where Turkish and Egyptian traders buy the crop on the plants and superintend its picking and preparation, which is by the dry method. Not much of this ever reaches the American markets, and the total amount of coffee now produced in Arabia, its ancestral home, is negligible. CHOCOLATEUnlike tea and coffee, chocolate is a native of the New World and was noticed by nearly all the The chocolate tree is scarcely over twenty-five feet tall, has large glossy leaves and bears rather small flowers directly on the branches or trunk. This unusual mode of flowering, common in rain forests, results in the large sculptured pods appearing as if artificially attached to the plant. Each pod, which may be 6 to 9 inches long, contains about fifty seeds—the chocolate bean of commerce. When the beans first come out of the pod they are covered with a slimy mucilaginous substance and are very bitter. To remove this the beans are fermented or “sweated,” usually by burying in the earth or piled in special houses for the purpose. After several days, sometimes as long as two weeks, the beans lose the mucilage, most of their bitter flavor and often change their color. After this they are dried and are ready for roasting, which drives off still more of their bitter flavor. Chocolate is Very little chocolate is now collected from wild plants, and cacao plantations are important projects in tropical agriculture. Because of its many varieties, some nearly worthless, the business was rather speculative until a few good sorts were perpetuated. Much valuable work on this plant and the isolation of many good varieties has been done by the Department of Agriculture in Jamaica, British West Indies. Cacao plantations are usually in moist, low regions near the coast, preferably protected from strong winds, to which the plant objects. The trees are set about ten to fifteen feet apart each way and begin bearing after the fifth or sixth year. The young plants are always shaded, often by bananas, which are cut off as the trees mature. The tree will not thrive unless the temperature is about 80 degrees or more and there should be preferably 75 inches of rainfall a year, about twice that at New York. Chocolate-growing regions are apt to be unhealthy for whites, and native labor is practically always used. The business is very profitable, but still somewhat speculative. 3. FibersNot only do plants furnish us with food and drink, but most of our clothing is made from plant products. There is annually produced twice as much cotton as wool, while linen is made from the fibers in the stem of the flax plant, which is also the source of linseed oil. Fibers occur in many different parts COTTONIt has been stated, perhaps a little rashly, that the value of the cotton crop in our Southern States exceeds all other agricultural products of the country. Whether this be true or no matters not, as cotton production and manufacture is certainly one of the most important industries of the world. Our own New England mills and those in Lancashire total an enormous volume of manufactured cotton goods, and what the stoppage of the cotton crop means to these industrial centers was shown even so far back as the Civil War, when the “cotton riots” in Lancashire were noised all over the world. Cotton is the most important of all fiber plants. There are several different kinds of commercially important cottons, and perhaps dozens of others, all derived from the genus Gossypium, a relative of our common garden mallows belonging to the MalvaceÆ. By far the most valuable is Sea Island cotton, derived from Gossypium barbadense, which is probably a native of the West Indies, although really In all of them the fiber is really an appendage of the seeds, and each pod as it splits open is found to be packed full of a white cottony mass of these fibers with the seeds attached. These white masses of cotton, or bolls, have to be picked by hand, as no really successful machine has ever been found for this purpose. Women and children do a large part of the picking, and the wastage due to careless picking is tremendous. The whole value of the cotton crop depends upon an invention by Eli Whitney, an In growing cotton in America seeds are sown in April, and the beautiful yellow flowers with a red center bloom about June or July, followed in August by the pod. This splits open and is ready for picking by September and October. The plants are grown in rows four feet apart and are set one foot apart in the row. Clean cultivation is absolutely necessary, and in first-class plantations all weeds are kept out. The plant needs a rich deep soil. HEMP AND CORDAGEThere are a variety of plants which furnish products known as hemp, but commercially only three are of much importance, the plant universally known under that name, the Manila hemp, and sisal. All of them are used chiefly for cordage. The hemp of the ancients is a tall annual related to our nettles, with rough leaves, and a native of Asia. For centuries an intoxicating drink was made from the herbage of this plant, and this with the The Manila hemp is derived from a banana (Musa textilis), that is a native of tropical Asia and is much grown in the Philippines. While the fruits of this plant are of very little or no value, the fiber from the long leafstalk is the best cordage material known. Also the finer fibers near the center of the stalk are made up into fabrics, which are rarely seen here, but are said to be almost silky in texture. As a cordage plant, however, Musa textilis is now easily the most important, and from a commercial point of view the Philippine Islands is the only From Yucatan, the Bahamas, and some other regions of tropical America comes the most valuable American cordage plant, known as sisal. The fiber is extracted from the thick coarse leaves of a century plant, known as Agave sisalina or Agave rigida, which looks not unlike the century plant so common in cultivation. The plant belongs to the Amaryllis family and is native in tropical America. Thousands of acres are planted to sisal in Yucatan and JUTEDuring the late war the Germans were reported to be sending flour and sugar to their armies pressed into large bricks for the want of bags to ship them in the ordinary way. Gunny sacks, or jute bags, as they are more often called, are made literally by the hundreds of millions, as practically all sugar, coffee, grains and feeds, and fertilizers are shipped in them. Jute is a tall herb, a native of the Old World tropics, but suitable for cultivation in many other tropical regions. Practically all the world’s supply now comes from India, probably because of the cheapness of labor rather than any peculiar virtue of the soil or climate of that country. The plant has been experimentally grown in Cuba with entire success, but labor conditions made cheap production of the fiber impossible. The jute plant, known as Corchorus capsularis or C. olitorius, grows approximately six to nine feet tall and is an annual, often branching only near the top. They are not very distantly related to our common linden tree. At the proper maturity the whole plant is harvested and the stems are tied into bundles ready for the retting process. Of all fiber processes this is the most difficult, largely because no machine or chemical has yet been found to extract the fiber of jute, or flax, and this is accomplished by placing the stems in water, which rots out the fleshy part of the stem, leaving the fiber. Some notion of the difficulty of this task in such plants as jute is gained by realizing that over twelve million bales of finished fiber are produced each year, and that the retting may take from two days to a month. The retting process is aided by certain organisms of decay in the water, by the temperature, and by some other factors not yet understood. The process is allowed to go on only long enough to separate flesh from fiber, which makes frequent inspection of the bundles in the filthy water an absolute necessity. Next to cotton jute is probably the most important fiber plant in the world. For hundreds of thousands of people in India and in England it is the only source of livelihood. To the inventor who can eliminate or reduce the costly retting process of jute, or of flax, which goes through essentially the same operation, there is waiting a golden future, for it is largely the cheapness of labor and willingness of its natives to stand in the retting pools that has made India the jute region of the world. Lack of space forbids mention of the many other fiber plants, some of which, like flax, are of large importance. Their fibers are used in a variety of ways and are found in different parts of the plant. A few of these, together with the names of the plants and the regions where they are native, are as follows:
No mention can be made here of the hundreds of fiber plants used by the natives of various parts of the world, some of them probably having great commercial possibilities. The extraction of these fibers by machinery or chemically will open up a large commerce in such plant products, the value of which is now unsuspected or ignored. While the value of cotton, jute, and Manila hemp is reckoned in the hundreds of millions, some of these native fibers are found in plants whose wild supply is almost inexhaustible, and some of which are quite as capable of cultivation as the better known fiber plants. Few fields of inquiry offer greater possibilities to the economic botanist than fibers. 4. The Story of RubberAlong the north coast of Haiti, particularly near Cap Haiti and Puerto Plata, there are scattered a few plantations devoted to rubber growing; and it is not without interest that Columbus on his first voyage landed at about this precise spot in December, 1492, and found the natives playing a game of ball made of rubber. He wrote: “The balls were of the gum of a tree, and although large, were lighter and bounced better than the wind balls of Castile.” This is apparently the first notice of the use of rubber, a substance now of world-wide importance, and derived from many other plants than the tree mentioned by Columbus. This is Castilla elastica, a native of certain islands of the West Indies and the adjacent mainland, and a relation of our common mulberry. For over three centuries rubber, or caoutchouc as it was often called, was only of very casual use before the process of vulcanizing was discovered by Charles Goodyear, an American, in 1839. This combination of rubber with sulphur transformed a material much subject to heat and cold, and of almost no manufacturing value, into one from which hundreds of articles of daily use are now manufactured. Previous to this it had been used mostly, and in fact almost exclusively, as a waterproofing material for cloth, a process much developed by the firm of Charles Macintosh & Co., who appear to have taken out the first patent for a waterproofing process in 1791, in England. The rubber tree found by Columbus is still grown in considerable quantities and is a valuable source of rubber, but it has been greatly overshadowed by a Brazilian tree which now This Brazilian tree, a native of the rich rain forests of the Amazon, is Hevea brasiliensis, and a relative of our common spurges of the roadsides and of the beautiful crotons of the florist, all belonging to the family EuphorbiaceÆ. The first important notice of this rubber appears to be by the astronomer C. M. de la Condamine, who was on an astronomical trip to the Amazon in 1735. He described Para rubber, as it has since been called, and by 1827 the export of this gum had grown to 31 tons a year. In 1910 Brazil exported over 38,000 tons, nearly all of which was collected from wild trees. After the discovery of vulcanization the demand for all kinds of rubber increased by leaps and bounds and it became obvious that the wild trees, The rubber of both Hevea and Castilla is produced from the milky juice or sap of the trees and is actually a wound response. As the trees are tapped the latex, as the milky juice is called, runs out of the wound and upon reaching the air coagulates. This material is removed and a new wound made, a process which is repeated for several years. There is still work to be done upon the problem of how often plantation trees should be tapped to get the greatest flow of latex without injuring the tree, but in many plantations it is done every day or every other day in the season, some rubber planters allowing a resting period during leaf fall, others again tapping almost continually. The actual wound is made by removing just enough bark to induce a flow of latex, but not until the wound is completely There are two other rubber-producing plants, neither of which are as important as Hevea and Castilla. One is the common rubber plant so much grown as a house plant and said to be much cherished for that purpose in Brooklyn. It is a kind of fig tree, known as Ficus elastica, a native of India and the source of India rubber. It was used for years, before the days of vulcanization, mostly for lead-pencil erasers. Thousands of acres of it in India were recently destroyed to make room for Hevea, although it still produces a respectable amount of rubber, inferior, however, to Hevea and Castilla. In Mexico a new source of rubber is the guayule rubber plant, a small shrub native of the drier parts of the Mexican uplands. It does not produce latex, as practically all other rubber plants do, but particles of rubber are found directly in its tissues, mostly in the bark. While of some importance, this shrub, known as Parthenium argentatum, a member of the CompositÆ or daisy family, is not 5. DrugsNearly all the drugs and medicines of importance are of vegetable origin, and from the days of Theophrastus the study of plants as possible medicines has been one of the chief phases of botanical research. In the early days all that was known about plants was learned by men interested in medicine, and some of their quaint old books are interesting relics of a bygone day. At present, pharmacognosy, or the science of medicinal plant products, is a highly developed specialty taught in medical and pharmacy schools. And yet the greatest medical college in this country has recently issued instructions to its staff of doctors and nurses to pay particular attention to “old wives’ remedies,” most of which consist of decoctions of leaves and other parts of plants. They have done this because all the knowledge of the scientists regarding medicinal plants has its origin in the habit of simple people turning to their local plants for a cure. The accumulation of the ages, aided and guided by the scientist, There is almost no part of a plant that, in some species at least, has not been found to contain the various acids, alkaloids, oils, essences, and so forth, which make up the chief medicinal or, as the pharmacists call it, the active principle of plants. In certain of them the most violent poisons are produced, such as the poison hemlock which killed Socrates, and the deadly nightshade. And again the unripe pod of one plant produces a milky juice so dangerous that traffic in it is forbidden in all civilized countries, and yet later the seeds from that matured pod are sold by the thousands of pounds to be harmlessly sprinkled on cakes and buns by the confectioners. Earlier in this book it was said that plants are chemical laboratories, and nowhere has this alchemy been carried to such a pitch of perfection as in the hundreds of drugs produced by different plants. Reference to special books on that subject should be made by those interested, as only a few of our most important drug plants can be mentioned here. QUININEThe Spanish viceroy of Peru, whose wife, the Countess del ChinchÓn, was dangerously ill of a fever in that country about 1638, succeeded through the aid of some Jesuit priests in curing the malady, with a medicine which these priests had gotten from the natives. It was a decoction from the bark of a tree, and its fame soon spread throughout the world as Peruvian bark. Even in those days malaria was the curse of the white man in tropical regions, and since For more than a hundred and fifty years after the discovery of Peruvian bark it was always taken as a liquid, usually mixed with port, and an extremely noxious and bitter drink it made. The fine white powder which we now use in tasteless pellets or pills has made the drug even more useful than before. The trees from which the bark is used all belong to the genus Cinchona, named for the first distinguished patient to benefit by it, and belong to the RubiaceÆ or madder family. There are at least four or five different species. For many years Peru and near-by states were the only source of the bark, and the English became convinced that the great trade in the drug would exterminate the tree, so in 1880 they introduced the plant into India. These cinchona plantations now provide most of the world’s demand, and some idea of what that means may be gleaned from the fact that in Ceylon alone over fifteen million pounds of the drug are produced annually. In India itself the plantations are largely government owned and quinine is sold in the post offices at a very low rate. In cinchona plantations strips of the bark are removed, and after a proper period ACONITEMost doctors use aconite for various purposes and it is mentioned here chiefly as illustrating a common characteristic of many medicinal plants. The whole plant is deadly poisonous, and in the root there appears to be a concentration of this poisonous substance, which makes the plant one of the most dangerous known. All of the drug aconite is derived from Aconitum Napellus, a monkshood, belonging to the buttercup family. It is a perennial herb with beautiful spikes of purple-blue flowers, not unlike a larkspur, and is a native of temperate regions of the Old World. A related Indian species has been used for probably thousands of years by the natives. They poison their arrows with it and so deadly is the drug that a tiger pricked by such an arrow will die within a few minutes. It is conceded to be the most powerful poison in India. Numerous accidents have resulted in Europe from careless collectors of the roots of horseradish, who sometimes get aconite roots mixed with that condiment, usually with fatal results. So many other plants are violently poisonous, and yet yield the most valuable drugs, that the greatest care has to be used in their collection and preparation. The habit of many children of eating wayside berries should be discouraged, as some of our most innocent-looking roadside plants are actually deadly if their fruits or foliage are eaten. Fortunately only a very few plants are poisonous to the touch, notably poison ivy and poison sumac, and some of their relatives. OPIUM AND MORPHINEAlmost no plant product has caused more misery and relieved more pain than the juice of the unripe pod of the common garden poppy, Papaver somniferum. From it opium is extracted, the chief constituent of which is morphine. If tea can be said to have precipitated our war of independence, opium was indirectly the cause of the opening of China to the western world. The degrading effects of opium had become so notorious that the Chinese in 1839 destroyed large stocks of it, mostly the property of British merchants, and prohibited further importations. In the subsequent negotiations which ended in war, China was opened up to trade. No civilized country now openly permits the sale of opium, although there is still a good deal of it used in practically all parts of the world. The effects of lassitude, subsequent ecstasy, and stupefaction are due to an alkaloid, the continued use of which forms a drug habit of serious consequences. Parts of China, Turkey, Persia, and Siam are said to be still large users of opium which is chewed, or more often smoked. Until comparatively recently fifteen out of every twenty men in some of these countries were regular users of the drug. The legitimate use of morphine by physicians has done more than almost anything else, with the possible exception of cocaine, to relieve suffering, and there is consequently a considerable trade in the drug. The home of this poppy is unknown, as it has been cultivated from the earliest days. The ancient Greeks and Romans knew it and the Egyptians grew it for opium. It is still grown in India and China, where, notwithstanding vigorous governmental COCAINEIn the northern part of South America the Peruvians and some of their neighbors were discovered by early explorers to be chewing the leaves of a native shrub, apparently with much profit and no evil after effects. It served them much as the betel nut does to the natives of India and other regions of the tropical East. With scanty or no food this apparently harmless intoxicant will carry both men and women over periods of severe fatigue. The Quite different in its effects has been the drug which has been extracted from this plant, known as Erythroxylon Coca. Far from being a beneficial and harmless stimulant, cocaine is now one of the drug evils of our time. Its use, outside that prescribed by physicians, is forbidden practically everywhere, but its consumption in this country, aside from its great and legitimate use as a relief from pain, is still very large. The number of drug plants is legion, so large in fact, that volumes have been filled with descriptions and notes about them. A few of the most important, omitting those already mentioned, are listed below:
6. The Story of TobaccoNot until 1492 was the use of tobacco known to the Europeans, when Columbus found the natives of Cuba and Santo Domingo both chewing and smoking it. Subsequent Spanish explorers of the mainland found its use almost universal both in North and South America. It had apparently been used there for countless ages, as smoking it formed part of the most solemn ceremonial rites both of the natives’ religion and their political gatherings. Brought to England in 1586 by Ralph Lane and Sir Francis Drake, the smoking of tobacco spread with the great speed that such a comfortable habit might be expected to exhibit. Notwithstanding violent opposition by certain priests and physicians and other more intolerant opponents of the weed, its use increased throughout the world. To-day, in spite of our modern anti-tobacco fanatics, over two billion pounds are produced annually, and in the United States there is a per capita consumption of over five pounds per year, greater than any country in the world, save Belgium. All of the many different forms in which tobacco is used are derived from the leaves of Nicotiana tabacum, or perhaps one or two other species of the genus Nicotiana, which belongs to the SolanaceÆ or potato family. There are many other species, all natives of the New World, but the actual home of the tobacco plant is in some doubt. As in so many cultivated plants, which have been grown for countless ages, wild specimens are practically unknown. The plant seeds freely and consequently frequently escapes from cultivation, so that in many parts of America apparently wild plants are to be found that trace their origin to cultivated plants. The antiquity of its culture may be gauged by the fact that in the most ancient Aztec tombs elaborately carved tobacco pipes have been found. The plant is grown as a field crop in rows from one and one-half to three feet apart and set about fifteen inches apart in the row. From the time the seed is sown until the harvesting of the leaves is usually three or four months, during which the plants demand the best of culture. In the United States thousands of acres of tobacco are now grown under cheesecloth shades, an expensive process which is more than compensated for by the improved flavor. Once the tobacco is cut there begin chemical changes in the leaves that are of great importance to its subsequent flavor and use. These are aided or induced first by a process of curing, which is accomplished by suspending the wilted leaves in the sun, a process that has been practically abandoned for curing by artificial heat. The leaves are hung in a building where slow fires bring the temperature up to 150 degrees F., which is maintained for a few days. The cured tobacco is then gathered into small bundles which are stacked or packed so closely that fermentation begins, often generating a temperature of 150 degrees F. The bundles are then reshifted and the process allowed to start again, which may be done several times, depending upon the quality of the leaf, flavor desired, and commercial requirements. Enzymes and bacteria play a large part in the fermentation process and inoculation of poor grades of tobacco with the organisms of finer grades has been tried. After fermentation has been stopped practically all tobaccos In Cuba, where its use was first noticed, the finest tobacco in the world is still produced, notably in the province of Pinar del Rio. It is still something of a mystery as to what peculiar combination of soil, climate, or handling the unquestionable superiority of the Cuban leaf is due. For one thing it is grown in the open, without shade, and is never cured by artificial heat. Nor is the very excellent cigarette tobacco of Turkey ever artificially cured. But attempts to imitate the conditions under which these finest grades of tobacco are produced outside Cuba and Turkey have never been really successful, so that those countries have practical monopolies on the production of the finest cigars and cigarettes. The weed is cultivated nearly throughout the world, even Canada producing considerable quantities, but the best kinds and greatest production is in warmer regions. It is second only to the sugar crop in Cuba, and the United States produces over one-third the world’s total supply. Immense quantities are grown, however, in India and Sumatra, and in the Philippines. Perhaps the most unusual and localized conditions of climate and subsequent handling are found in the production of perique tobacco. All the world’s supply is grown on a ridge at Grand Point, in the parish of St. James, Louisiana. The leaves are subjected to great pressure and the expressed juice, after oxidation, is reabsorbed by the leaves after the pressure is removed. The peculiar flavor is apparently due to this and to the damp climate. Perique is now used throughout the world as an ingredient of the better kinds of pipe tobacco. The diseases and breeding of different strains of tobacco are commercial factors of tremendous importance to the industry. With a yearly value of well over two billions of dollars, the crop is one of the most important plant products, outside of foods. The capital invested in America alone is over five hundred million dollars. 7. SpicesAs we have seen many of our most valuable food plants are natives of and are now cultivated in temperate regions, but “sugar and spice and all things nice” mostly come from the tropics. What we usually know as spices such as nutmeg, vanilla, ginger, mace, cloves, allspice, and cinnamon are practically all confined to the tropical regions in or near the East Indies, only vanilla being of American origin. The trade in these spices has been for hundreds of years a practical monopoly in the hands of Dutch and British traders, and for hundreds of years before that the caravans from the Far East came laden with precious freight from the then mysterious country beyond the Mediterranean. VANILLAThe long pods of two climbing orchids native in Central America and the West Indies furnished for many years our only supplies of this flavoring extract. But in 1891 a process of making vanilline chemically from sugar was perfected so that the vanilla trade is not what it was years ago. Vanilla planters, however, have been able to keep up the price of the plant product because of its unquestionable superiority over the manufactured article. But the latter has enormously increased the general use In both species, known as Vanilla pompona and Vanilla planifolia, the orchid has flat leaves and a fleshy climbing stem that hugs tree trunks or other supports, always in the dense shade of the tropical forests. It needs a hot moist climate, but if there be too much rain as the pods are ripening they drop off, so that only certain localities are suited to its cultivation. Various islands are apparently better suited to the plant than the mainland, Tahiti producing alone nearly half the world’s supply. The species most cultivated is Vanilla planifolia, which came originally from southern Mexico, where considerable plantations are still maintained. The pods are about as thick as a thumb or finger and from five to seven inches long, and yellow when ripe. The ripening process takes several months and when completed the pod is still without the delicious fragrance for which it is famous. Curing by dipping in boiling water or by fermentation, a very delicate process requiring long experience, brings out the flavor. In some regions the pods are plunged into ashes and left there until they begin to shrivel when they are cleaned off, rubbed with olive oil, and tied at their lower end to prevent splitting. Still another process demanding that the pods be plunged in rum is followed, but only in limited degree, owing to the expense. In all of them the result is the same—that of inducing chemical changes in the pod which are responsible for its subsequent flavor. NUTMEGA small tree of the tropical regions of eastern Asia, known as Myristica fragrans, or perhaps better as Myristica moschata, is the source of both nutmeg and mace which come from different parts of the same plant. The genus contains over one hundred species, belongs to the MyristicaceÆ, and is scattered all over the Malayan region. Almost none of its relatives, however, have the fragrance of the nutmeg and none is used as a spice. Both nutmeg and mace have been known in Europe only from about 1195 A.D., when in a poem about the entry of the Emperor Henry VI into Rome, the streets were described as being perfumed by the burning of nutmegs and other fragrant plants. It was not until the rise of the Dutch, who burned large stores of it at Amsterdam in 1790 in order to keep up a falling price, that nutmegs came into general use. The trees are now chiefly cultivated in the Dutch The trees produce male and female flowers, usually on different plants, but sometimes on the same one, yellow in color and aromatic. From the females are developed the fruit which is a drupe about two inches long with a thick fleshy husk which splits upon ripening. The seed inside is the nutmeg, but from its base is an outgrowth which covers the nut with a “splendid crimson network.” This covering or network is removed by hand and forms the mace of commerce. CLOVESIn the family MyrtaceÆ, which contains hundreds of plants from all over the world, mostly all shrubs and trees of tropical regions, however, there is a large genus, Eugenia. From the unopened flower buds of Eugenia caryophyllata, a small tree native only on a few islands in the Moluccas, the widely used spice known as cloves is derived. It appears to have been known to the Chinese at least two hundred years before Christ, and was regularly imported into Europe from the eighth century by caravans. Not until the Dutch began to import it by ship did it become cheap enough to have general use, but in 1609 a Dutch vessel reached England with over a hundred thousand pounds on board. While the tree is of very local distribution, it has been introduced on a considerable scale into Penang, Zanzibar, and even to the West Indies. Trees are set out thirty feet apart each way, and in from four to eight years, depending on the locality, they begin to flower. After the full bearing stage is reached, a tree will produce from five to seven pounds of CINNAMONOne of the commonest trees in the lowland parts of Ceylon is Cinnamomum zeylanicum, a tree of the family LauraceÆ, which also contains our native sassafras. From the bark of this tree is derived cinnamon, and from a related Japanese tree, Cinnamomum Camphora, camphor is taken. Practically all the LauraceÆ are aromatic shrubs or trees, While the wild cinnamon trees reach considerable heights, the cultivated plants are cut so regularly that they almost always throw up a lot of young shoots from the roots, and it is the bark of these that furnishes the spice. When the bark is fit for peeling, the natives cut off the shoots, and strip the bark from them by hand, but with a specially constructed Other spice plants and condiments are of wide use, but can scarcely be mentioned in detail here. A few of the more important are the following:
This brief review of what the plant world provides us with in the shape of foods, beverages, fibers, drugs, rubber, spices, and tobacco, does not begin to tell us what man’s debt to plants really is. Thousands of plants, used by natives all over the world, may well provide future generations with unsuspected sources of plant products. No mention has been made of timbers nor all the forest products, except paper, which in the aggregate total an enormous sum. Perhaps no better idea of the tremendous value of plants, of the absorbing interest their utilization has always had for man, can be gained than to refer the reader to incomparably the best book on the subject, so far as tropical plants are A few more economic plants not yet noted are listed below, and with this our account of plants as they are used by man must close:
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