A seed drill sows seeds in a straight, constant-depth furrow at regular intervals. As it travels over the furrow, the dirt is reapplied to the seeds. The seed drill comprises of a seed hopper, plough, and harrows, and can be hauled by a horse or tractor or manually pushed.
Jethro Tull of England invented the seed drill in 1701. Before the introduction of the drill, farmers dispersed seed by hand, a procedure known as “drilling.” The advent of the seed drill made it possible for farmers to plant seeds at a constant depth and distance apart, resulting in increased seed germination and agricultural yields. Additionally, straight rows of plants could be mechanically farmed considerably more efficiently than plants grown from seeds scattered by hand.
Modern seed drills vary in complexity, but they all have the same fundamental components. The front of the seed drill is equipped with a plough attachment that cuts through the soil as the drill advances, creating a straight furrow of constant depth. A seed hopper, which typically consists of a revolving perforated barrel or set of cups, contains a reservoir of seeds and drops them into the furrow one by one. Mounted on the rear of the seed drill, the harrows push soil back onto the seeds that are seated in the furrow. This assembly can be connected serially to produce seed drills that can plant up to sixteen rows of seeds simultaneously.