Seed drill China, and later a seed drill by Jethro Tull that was influential in the growth of farming technology in recent centuries. Even for a century after Tull, hand sowing of grain remained common. In older methods of planting, a field is initially prepared with a plow to a series of linear cuts known as "furrows". The field is then seeded by throwing the seeds over the field, a method known as "manual broadcasting". The seeds may not be sown to the right depth nor the proper distance from one another. Seeds that land in the furrows have better protection from
Seed drill hopper filled with seeds arranged above a series of tubes that can be set at selected distances from each other to allow optimum growth of the resulting plants. Seeds are spaced out using fluted paddles which rotate using a geared drive from one of the drill's land wheels—seed rate is altered by changing gear ratios. Most modern drills use air to convey seed in plastic tubes from the seed hopper to the coulters—it is an arrangement which allows seed drills to be much wider than the seed hopper—as much as 12 m wide in some cases. The seed is metered