AGRICULTURE, the art of cultivating the ground, whether by pasturage, by tillage, or by gardening. In many countries the process of human economical and social development has been from the savage state to hunting and fishing, from these to the pastoral state, from it again to agriculture, properly so called, and thence, finally, to commerce and manufactures, though even in the most advanced countries every one of the states now mentioned, excepting only the first, and, in part, the second, still exist and flourish. The tillage of the soil has existed from a remote period of antiquity, and experience has from time to time improved the processes adopted and the instruments in use; but it was not till a very recent period that the necessity of basing the occupation of the farmer on physical and other science has been even partially recognized. Now a division is made into theoretical and practical agriculture, the former investigating the scientific principles on which the cultivation of the soil should be conducted, and the best methods of carrying them out; and the latter actually doing so in practice.

The soil used for agricultural purposes is mainly derived from subjacent rocks, which cannot be properly understood without some knowledge of geology, while a study of the dip and strike of the rocks will also be of use in determining the most suitable directions for drains and places for wells. The composition of the soil, manures, etc., requires for its determination agricultural chemistry. The weather cannot be properly understood without meteorology. The plants cultivated, the weeds requiring extirpation, the fungus growths which often do extensive and mysterious damage, fall under the province of botany; the domestic animals, and the wild mammals, birds and insects which prey on the produce of the field, under that of zoölogy. The complex machines and even the simplest implements are constructed upon principles revealed by natural philosophy; farm buildings cannot be properly planned or constructed without a knowledge of architecture. Rents can be understood only by the student of political economy. Finally, farm laborers cannot be governed or rendered loyal and trustworthy unless their superior knows the human heart, and acts on the Christian principle of doing to those under him as he would wish them, if his or their relative positions were reversed, to do to him. Notwithstanding the enormous expansion of the manufacturing industries in the 19th century, agriculture is still the greatest of the occupations of man.

Historical and General Aspects.—In all countries and ages, history records no instance of any civilization attained without noteworthy progress in agriculture. The relationship of agriculture to population expansion is one of the vital questions for economists. It appears that, in times so remote that their antiquity is only conjecturable, an excellent system of agriculture supported, in the valleys of the Nile and Euphrates, populations at least as dense as any existing to-day. The same agricultural perfection, attended by much the same exceptional conditions of the population which distinguished the oldest civilizations of the world, is still conspicuously characteristic of such Oriental countries as retain any national vitality, especially India, China, and Japan. For instance, Japan contains more inhabitants than the United Kingdom, and supports them without taking any food products from abroad (actually, indeed, exporting considerable quantities of rice), whereas England imports foodstuffs to the value of hundreds of millions of dollars.

In the Middle Ages, agriculture was almost wholly disregarded throughout Europe, and, consequently, civilization was generally at a low ebb. On the other hand, the era of the Saracens in Spain is memorable for civilization, and particularly for its admirable agriculture. Without exception, all the European nations that enjoy eminence to-day possess carefully developed agricultural systems, while in Spain, the one noticeably backward country, agriculture languishes. It is proverbial that the wealth of France is not in her luxurious capital, but in her provincial acres. Belgium and Holland, the richest regions of Europe in proportion to area, with populations correspondingly dense, owe their pre-eminence to the elaborate cultivation. The collapse of the Mohammedan power finds one of its chief explanations in the indolence of the Turk and his neglect of the soil.

The first mention of agriculture is found in the writings of Moses. From them we learn that Cain was a “tiller of the ground”; that Abel sacrificed the “firstlings of his flock”; and that Noah “began to be a husbandman and planted a vineyard.” The Chinese, Japanese, Chaldeans, Egyptians, and Phœnicians appear to have held husbandry in high estimation. The Egyptians were so sensible of its blessings that they ascribed its invention to superhuman agency, and even carried their gratitude to such an excess as to worship the ox, for his services as a laborer. The Carthaginians carried the art of agriculture to a higher degree than other nations, their contemporaries. Mago, one of their most famous generals, wrote no less than 28 books on agricultural topics, which, according to Columella, were translated into Latin by an express decree of the Roman Senate. Hesiod, the Greek writer, supposed to be contemporary with Homer, wrote a poem on agriculture, entitled “Weeks and Days,” which was so denominated because husbandry requires an exact observance of times and seasons. Other Greek writers wrote on rural economy, and Xenophon, among the number, but their works have been lost in the lapse of ages. Columella, who flourished in the reign of the Emperor Claudius, wrote 12 books on husbandry, which constituted a complete treatise on rural affairs. Pliny ascribes the invention of manures to the Greek King Augeas, and Theophrastus not only mentions six kinds of manures, but declares that a mixture of soils produces the same effects as manures. Cato, the Roman censor, equally celebrated as a statesman, orator, and general, derived his highest and most durable honors from having written a voluminous work on agriculture. In the “Georgics” of Vergil, the majesty of verse and the harmony of numbers add dignity and grace to the most useful of all topics. Varro, Pliny, and Palladius were likewise among the distinguished Romans who wrote on agricultural subjects.

It is interesting to note here that irrigation had an influential advocate as long ago as the time of Vergil, who in his “Georgics” advises husbandmen to “bring down the waters of a river upon the sown corn, and, when the field is parched and the plants drying, convey it from the brow of a hill in channels.” To the credit of the Romans let it be remembered that, unlike many conquerors, instead of desolating they improved the countries which they subdued, and first of all in agriculture.

Recent Progress.—From the details of primitive agricultural methods given in ancient writings and represented in monumental inscriptions, it is evident that not till the 19th century had anything very material been done toward the creation of a distinctive agricultural science. The original arts of husbandry, practiced ages ago, have simply been adapted, with little improvement till very lately, to modify conditions. Most of the mechanical appliances to which our ancestors were restricted—the plow, roller, hoe, sickle—are found pictured in the Egyptian inscriptions and paintings. It is also known that the Egyptians were familiar with the advantages of rotation in crops, and that they were exceedingly intelligent and systematic in the administration of estates and the regulation of all rural concerns.

Within the last hundred years, however, the foundations of an entirely new agriculture have been securely laid. The two active agencies in this change have been chemical science and invention. Chemical science, as applied to agriculture, is based on very simple elements. The arable surface soil becomes exhausted if grain is sown upon it in successive years, this exhaustion being occasioned by the removal of the mineral substances necessary to the life of the grain. By the system of rotation, a cereal crop is followed by a so-called green crop, the roots of which penetrate deep into the subsoil and extract from it a fresh supply of the needful minerals; thus the vigor of the surface soil is renewed and it again produces an abundant grain crop.

The fundamentals of the new rural economy are to secure maximum productiveness on the agricultural lands, as a whole, by a comprehensive utilization of a great variety of fertilizers, and, by studying the needs of the soil, to apply to them the particular fertilizers best adapted to their nature. The demonstrations of experimental chemistry in these directions have been so effective that agricultural science has become one of the leading subjects of practical investigation, receiving the actual encouragement of all civilized governments. The energetic spirit stimulated by the latest teachings of chemical science has reflected constant advance in all other departments of scientific agriculture, such as drainage, irrigation, the improvement of breeds and plants, meteorology, etc.

Agricultural Interests and the Government.—The growth of agriculture and the evolution of enlightened governmental administration have uniformly gone hand in hand. The great distinguishing characteristic of the Dark Ages in Europe was the crushing oppression of the rural population. The lifting of the arbitrary burdens resting on the agricultural class has in all countries marked the beginning of the era of enlarged civil liberty and of diffused intelligence. The marvelous progress of the United States is above all the result of the rapid absorption of lands by its own native citizens and by industrious immigrants from Europe. From the earliest period the Federal Government, having enormous tracts of unoccupied lands at its disposal, pursued an extremely liberal policy to encourage settlement. Thus, in a brief time, every section of the country was peopled and the foundations of a great commonwealth were laid. With the vigorous revival of enterprise and thrift after the Civil War, and the steady advance of immigration, the epoch of abundant, fertile lands obtainable for a nominal price was brought to its close; and the intense rivalry witnessed at the opening of Oklahoma Territory was a demonstration of the practical termination of the era of settlement. In a new country, the soil of which has been accessible to all, the farmers have not been prompt to turn their attention to the strictly scientific aspects of agriculture, yet the government has manifested appreciation of the spirit of the age and the needs of the future by its generous provisions for the founding of agricultural colleges, and by its admirable system of agricultural experiment stations. The latter, like the agricultural colleges, are modeled upon the technical institutions originated in Europe for scientific investigation concerning all the branches of agriculture. The Federal Government makes an annual grant for experiment station purposes to each State and Territory in which an agricultural college is in operation, and some of the States also contribute to the support of the stations. The Department of Agriculture of the National Government is excellently equipped for the promotion of agricultural interests in both practical and experimental aspects. Its Weather Bureau, Bureau of Animal Industries, and various divisions, are constantly performing work of much value, and a great variety of useful information is systematically disseminated.

The following tables give the acreage, value, and production (000 omitted) of the principal agricultural crops in 1919:

Statistics of other products not included in the tables above are as follows: peanuts, 1,251,400 acres, production 33,263,000 bushels, value $79,839,000; beans, 1,018,000 acres, production 11,488,000 bushels, value $49,181,000; sweet potatoes, 1,029,000 acres, production 103,579,000 bushels, value $138,085,000; hops, 23,900 acres, production 29,346,000 pounds, value $22,656,000. The total value of thirteen crops in all the States in 1919 was $12,421,342,000. The total value of live stock on the farms in 1920 amounted to $8,566,313,000.