Sowing
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Sowing is the process of planting seeds.
Hand sowing is the process of casting handfuls of seed over prepared ground: broadcasting. Usually, a drag or harrow is employed to incorporate the seed into the soil. Though labor intensive for any but small areas, this method is still used in some situations. Practice is required to sow evenly and at the desired rate. A hand seeder can be used for sowing, though it is less of a help than it is for the smaller seeds of grasses and legumes.
In agriculture, most seed is now sown using a seed drill, which offers greater precision; seed is sown evenly and at the desired rate. The drill also places the seed at a measured distance below the soil, so that less seed is required. The standard design uses a fluted feed metering system, which is volumetric in nature; individual seeds are not counted. Rows are typically about 10-30 cm apart, depending on the crop species and growing conditions. Several row opener types are used depending on soil type and local tradition. Grain drills are most often drawn by tractors, but can also be pulled by horses. Pickup trucks are sometimes used, since little draft is required.
A seed rate of about 100 kg of seed per hectare (2 bushels per acre) is typical, though rates vary considerably depending on crop species, soil conditions, and farmer's preference. Excessive rates can cause the crop to lodge, while too thin a rate will result in poor utilisation of the land, competition with weeds and a reduction in the yield.
Among the major field crops, oats, wheat, and rye are sowed, grasses and legumes are seeded, and maize and soybeans are planted. In seeding, little if any soil is placed over the seeds. In planting, wider rows (generally 75 cm (30 in) or more) are used, and the intent is to have precise, even spacing between individual seeds in the row; various mechanisms have been devised to count out individual seeds at exact intervals.