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increases the yield, is most destructive to weeds and insects, and is the most economical in farm management. For winter wheat, the ground is plowed as soon after harvest as is practicable. This destroys the weeds before they ripen their seed and gives time for a compact seedbed. The pulverized surface soil more readily retains and absorbs moisture, upon which, in the absence of vegetation, no demands are made by growth. The depth of plowing should vary with the climate and with the nature of the soil and the subsoil. The limits of the variations usually found advantageous are between four and eight inches in depth.
Subsoiling.—As the common plow is in effect a wedge passing through the soil on a horizontal plane, the uppermost layer of the subsoil is compacted at each plowing. This renders the subsoil more impervious to water and roots. Subsoiling consists in breaking up the subsoil, and does not necessarily involve changing the relative positions of subsoil and topsoil. Judged by experiment station results, it does not seem to be an economical operation.
The Seed Bed.—Soil, on account of its fine texture or wet condition, may be lumpy after plowing. The spaces in it are then very irregular in size, and the soil is in a poor condition to draw up water from below, or to furnish uniform germinating conditions for the seed. In such cases it is customary and advisable to work the soil with a harrow, roll, or other implement until the larger lumps are broken and the surface becomes smooth and even. The seed bed is then ready for the sowing. Thorough preparation conserves the moisture, diminishes winterkilling, and increases the yield. In both the spring and winter wheat districts of the Mississippi valley, it is a general practice to sow without plowing on land that has produced corn the preceding year. In the case of winter wheat, the grain may simply be drilled between the rows of corn, with a five-hoe drill, or the seedbed may first be prepared with a disc or tooth harrow. Corn ground for spring wheat also is often prepared by using an implement of the disc harrow type.
Sowing.—There are three methods of sowing wheat: Broadcasting, which scatters the seed evenly over the ground; drilling, which places it in rows; and dibbling, in which a certain number of grains are dropped in each hill by means of a dibbling iron. Diverse means have been employed in each method. Dibbling, once quite extensively practiced in England, is never found now, unless it is with the experimenter. Nature's method, broadcasting, was also the first method of artificial seeding. The seed was simply scattered by hand. Of the three ways, drilling is now recognized as the most advantageous. The conclusion from station experiments is that the increase in yield will amply pay for any extra cost involved in drilling.1 Less seed is required, for the wheat is more uniformly distributed and covered. If it is sown at an even depth in moist soil, quick germination results. This places weeds at a disadvantage, especially in spring wheat. Drilling also decreases the danger from drought, winterkilling, and the blowing of soil by the winds. The snow lodged in the furrows left by the drill affords protection and moisture.
Seeders.—After hand sowing came the seeder, which accomplished the same results mechanically. Such machines are by no means modern, though in England and Germany they can be traced only to the beginning of the seventeenth century. The ancient Chinese, Persians, Hindoos and Romans used them, as well as the drill, which was doubtless the next seeding machine to be invented. Ardrey maintains that the first historical knowledge of a seeder pertains to an Assyrian drill used many centuries before Christ. The Egyptians of 3000 B. C. sowed by hand, the method still widely followed all over the world where the farms are very small, or where the standard of farming is not high, as, for example, among the lower classes of Russian peasantry. In early England the wheat was sown into the plow furrow, often by a mere child, who carried a bag or wooden hopper (known as a seedlip or seedcod) full of grain in front of the horses or oxen drawing the plow. The same practice prevails in east central India, a woman taking the place of the child. By another method in India, the seed is thrown through a tube attached to the plow handles.
Jethro Tull introduced the drill in England in 1730. His first machine sowed three rows of wheat at a time. In 1851 1 Hunt. Cereals in Amer (1904). p. 84.
Pusey wrote: "The sower with his seedlip has almost vanished from southern England, driven out by a complicated machine, the drill, depositing the seed in rows, and drawn by several horses." In America, the first patent granted on a seeding machine was in 1799. A slide broadcast seeder, which was a riding implement, was patented in 1835; the rotary broadcast seeder came in 1856; the grain drill in 1874; and the riding grain drill in 1884.
The Wagon Seeder is the best machine that has ever been devised for rapidly broadcasting wheat. It is mounted on a special tail-board, which, when the machine is used, is substituted for the tail-board of the wagon. It consists of a seedhopper; a driving shaft connected by a sprocket chain with a sprocket wheel fastened to one of the rear wagon wheels; a rotating seed plate in the bottom of the hopper; and a
A MODERN PRESS DRILL WITH DISCS
distributing wheel shaped like a windmill. The grain falls upon the distributing wheel, from which it is effectively scattered by centrifugal force. In the ordinary force-feed seeder gravity does the distributing, but here the additional factor of the centrifugal force given by the distributing wheel is involved. Two men and one team can broadcast 100 acres a day with this machine.
The Press Drill is similar to the ordinary broadcast seeder in that it carries, parallel to the axis of its two wheels, a seed-box having a number of seed-cups in its bottom. From these cups the seed is brought by feed-wheels which are attached to a revolving shaft. This force feed was the first great improvement over utilizing gravity alone for the purpose of distributing the seed. The grain falls into a tube, which, instead of scattering it as in the seeder, carries it in a steady stream to the bottom of the shoe. The soil is pressed laterally by the shoe, and the seed finds a moist bed in which to germinate. It differs from the ordinary drill in that it presses a V groove instead of scratching a trench. The press or shoe drill has largely superseded the hoe drill, especially in the far west. Disc drills are also used, but they are not adapted to stony, hilly or wet land. Drills and broadcast seeders are made in standard widths of 8, 11 and 14 feet. The tendency in recent years is to drill in the wheat, except perhaps in California. In the Red river valley four-horse press drills covering 12 feet are used. About 30 acres a day are sown by one man, and no
A TYPICAL FORCE FEED BROADCAST SEEDER subsequent cultivation is necessary. By the old method of seeding by hand, one man could sow about 16 acres per day, and the wheat had to be cultivated into the ground after it was sown.
The Order in Which Seeders Have Evolved is somewhat as follows: (1) Sowing by hand; (2) the broadcast seeder, taking the place of the hand, the flow of the seed depending on gravity; (3) the broadcast seeder with force feed; (4) the ordinary drill with a force feed putting the grain in evenly in rows and deeper; (5) the press drill, which is now the best machine we have for seeding. In the absence of wind, the hand grass seeder can be used advantageously for broadcasting small