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Perhaps the only region in the world where nature still occasionally seeds the ground by her own methods so efficiently as to produce a crop is on the Pacific coast of the United States. Some wheat is nearly always "shed" or shelled out before or during harvest, and, if cultivatel into the ground by harrowing or discing, produces what is known as a "volunteer" crop. If not enough has been shed, frequently a little more is scattered over the field, and instances are not uncommon where 25 to 30 bushels per acre have been yielded by such volunteer wheat lands.

The Amount of Seed required per acre varies with time and method of seeding, with soil and climate, with different varieties of wheat, and even with size and quality of seed of the same variety. One variety may have only half as many grains in a bushel as another. A bushel of shriveled wheat will have more grains than a bushel of plump wheat. The lower the germinating power, the more seed will have to be sown per acre. Less seed is required if the time is early, if the rainfall is light, if the soil is fertile, if the seedbed is well prepared, and if the grain is drilled. The yield, however, is not proportionate to the seed sown, for by tillering more or less, the wheat plant adjusts itself to its environment. The most usual amount sown per acre in the United States is about 5 pecks. It varies from 2 pecks in parts of California to 9 pecks in Ohio. The average amount sown per acre in the United States is 1% bushels in the winter wheat regions, iy2 bushels in the spring wheat regions, 7 to 9 pecks in the Middle Atlantic states, 6 to 8 pecks in the Mississippi and Ohio valleys, and 3 to 8 pecks in California.1

The Time of Seeding varies so much with soil, climate and different varieties of wheat that, taking the world around, any time during the entire year is the best time for some particular locality. For the United States Carleton says: "It is a pretty safe rule to follow the practice of sowing always at a date which is considered to be early in that locality. At the proper time the seeding should be done at once, without regard to weather conditions."1 Local conditions must always determine the time for any particular locality. For example, if an attack of Hessian fly is imminent in a certain region, the farmers should take concerted action for later sowing. Spring wheat should usually be sown as soon as the ground is in a condition for seeding. Winter wheat sown too late lacks the vitality needed to withstand the cold, and sown too early it produces a rank and succulent growth that is injured by freezing.

1 Hunt, Cereals in Amer. (1904). p. 86.

2 Yearbook U. S. Dept. Agr., 1900, p. 541.

The Depth of Seeding varies with the nature of the soil, the amount of moisture, and the condition of the seedbed. In a dry, sandy or cloddy soil, it is necessary to sow deeper than in a wet, clay, or level soil. Ordinarily, the wheat should be covered with about one inch of moist soil.

Harrowing.—After the ground is once plowed, the implement most commonly used for further cultivation, either before or after sowing the wheat, is the harrow. There are three principal objects in harrowing: (1) To kill weeds and grass, which would otherwise absorb moisture and nourishment needed by the wheat; (2) to level the surface and to keep it covered with a loose, dry mulch, both of which also conserve moisture; and (3) to cover the seed. In drilled wheat the latter is performed in sowing. All three of these objects may be attained in one operation.

The most primitive method of harrowing was to drag over the ground the limb of a tree with extending branches. This implement, like the rude plow, is often found reappearing on the frontier of civilization. It is easily improved and widened by fastening together a number of branches so that it does better work and covers a wider area. In California, in 1835, the wheat was sown broadcast by hand and brushed in with the branch of a tree drawn twice over the ground. The writer can well remember when, as late as the middle eighties, he brushed wheat into the ground with a "drag" made from scraggy wild plum trees cut on the banks of the Dakota river. A similar implement was also used in other parts of the United States. Another very primitive method of covering the grain was that used in ancient Egypt, where it was trampled into the loose ground by the hoofs of animals.

The Romans used a kind of harrow before the Christian era. In 1534 harrows with iron teeth were used in England, as well as some with wooden teeth. In Northumberland, in 1650. "the harrow was constructed without joints and without iron, of branches of the mountain-birch, fixed together with wooden pegs, with tines of the tough broom."' The oldest and simplest form of the harrow had a wooden frame with teeth of wood or iron. As it was drawn over the field, it combed or raked the surface quite level. Two improvements have since been made. It is constructed in two or more sections so that it can accommodate itself to uneven ground; and flexible steel bars are used in the frame so that by means of a lever the teeth can be set at any angle. Harrows 25 feet in width are now used on the large western farms of the United States. With such a harrow one man and four horses can cover 60 to 75 acres per day.

Various other forms of harrows have been devised. The principal ones are the spring tooth and the disc harrows. The latter consists of a main frame to which are pivoted two supplementary frames. Mounted within each one of these is a shaft carrying a series of concavo-convex discs, and the whole series is rolled over the ground. Adjusting levers swing the supplemental frames to any angle in relation to the line of draft. The soil is cut and thrown out in a degree proportional to the angle set. It was first used by the Japanese in ancient times. In the last decade the disc principle has been widely applied to harrows, plows and cultivators. Cultivation by one Operation.—As early as 1618 a machine, worked by steam, was invented and patented in England which plowed and fertilized the land and sowed the seed, all at one operation.1 There is no record of its having done any work. In the same country a "double-hoppered drill-plough" was advertised as a new machine in 1744. It drilled and covered wheat and fertilizer together. Perhaps the only instance where any practical and extensive results in this line have been obtained is in California and northwestern Canada. Gang plows are used, and a broadcast seeder attached to the rear of the plow sows the seed as fast as the ground is plowed. The seeder is usually followed by a harrow, also attached to the plow. A small outfit, operated by one man and drawn by a team of eight mules, will plow, sow and harrow-in the seed in one operation at the rate of from 10 to 15 acres per day. On the large farms 1 Grey, Agr. in Northuinti. , p. 4.

* Perels, Bedeutung des Machinenwesens, etc., pp. 11-13.

this machinery is combined into great gangs drawn by a powerful traction engine, and such outfits may cover from 35 to 100 acres per day.

Cultivation Subsequent to Sowing.—As a rule, in most countries wheat receives no cultivation between sowing and harvesting. Occasionally, however, it is harrowed or rolled after the seed has germinated, or after it has made some growth and become firmly rooted. This is done to kill weeds or retard evaporation. Ordinarily, such cultivation has not been found of advantage in modern wheat growing. In Japan wheat is planted in rows and hoed, but vegetables are usually raised at the same time between the rows. In the time of Fitzherbert, a kind of wooden shears or hook was used in pulling the weeds out of wheat. In the eighteenth century when wheat was drilled in England, it was hoed with a mattock or hoe.

Pasturing winter wheat is practiced to a certain extent. This should never be continued late in the spring, or when the soil is not in suitable condition, for yield and quality of wheat will then be lowered. If judiciously practiced, there may be no reduction in yield.1 1 Okla. Bui. 65, p. 6.



Risks and Customs of the Harvest Period.—Man has a regulative control that is sufficient to insure a crop over so few of the essential conditions of wheat growing that there is always a very large element of risk involved from the time the wheat is sown until it is harvested. Increasing control due to accumulating knowledge acquired from past experience continually diminishes the risk. When a balance of all these things has been struck, however, the fact remains that the modern wheat grower is playing with many factors, anyone of which may cause a partial or complete crop failure. Extremes of heat and cold; drought; superabundance of rainfall; destructive hail or wind storms; floods; parasitic plants, such as smut and rust; predatory insects, birds and rodents; fire; various diseases and other unfavorable conditions may defeat all means to success at the farmer's command. Thus wheat raising, like most of the extractive industries, has a large aleatory element which cannot be eliminated, though it may be reduced to a constant factor by means of the insurance principle, to which we will give subsequent attention.

This risk which is involved reaches its maximum at the harvest period. In most regions wheat must be promptly harvested when it is ripe. If not then attended to, not only is the period of risk prolonged when there is no possibility of further gain, but an actual loss is sustained under the most favorable conditions, and the grain is also more susceptible to the destructive influences of its environment. The grain will now be shelled or lodged by wind previously harmless, many birds seek food in the ripened fields, and the rain causes the seed to lose color and to sprout. The ripening grain must be closely watched, for the determining change in the heads may occur between one day and the next. The field must usually be harvested within two weeks.

In wheat raising the whole year's toil meets with no reward before the harvest. If this is lost, the fruits of all previous

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