Seed drill

A seed drill is a device for planting seeds in the soil. Before the introduction of the seed drill, the common practice was to "broadcast" seeds by hand. Besides being wasteful, broadcasting was very imprecise and led to a poor distribution of seeds, leading to low productivity.

Functionality

The seed drill allows farmers to sow seeds in well-spaced rows at specific depths at a specific seed rate; each tube creates a hole of a specific depth, drops in a seed, and covers it over. Prior to this farmers simply cast seeds on the ground, by hand, for them to grow where they landed (broadcasting).

This invention gave farmers much greater control over the depth that the seed was planted and the ability to cover the seeds without back-tracking. This greater control meant that seeds germinated consistently and in good soil. The result was an increased rate of germination, and a much-improved crop yield (up to eight times [ [http://www.economist.com/displaystory.cfm?story_id=E1_VPNPPGN The story of wheat | Ears of plenty | Economist.com ] Paid subscription required] ).

A further important consideration was weed control: in the days before selective herbicide, drilling afforded the ability to hoe the crop during the course of the growing season. Weeding by hand is laborious and poor weeding limits yield.

History

The Sumerians used primitive single-tube seed drills around 1,500 BCE, but the invention never reached Europe. Multi-tube seed drills were invented by the Chinese in the 2nd century BCE."The Genius of China", Robert Temple, p.25]

The first known European seed drill was invented by Camillo Torello and patented by the Venetian Senate in 1566. A seed drill with a detailed description is known from Tadeo Cavalina of Bologna in 1602. In England, the seed drill was further refined by Jethro Tull in 1701 in the Industrial Revolution. It is often thought that the seed drill was introduced in Europe following contacts with China, where the invention was very ancient and highly developed. Seed drills would not come into major use in Europe until the mid-19th century.

Over the years seed drills have become more advanced and sophisticated but the technology has remained substantially the same. The first seed drills were small enough to be drawn by a single horse but the availability of steam and, later, gasoline tractors saw the development of larger and more efficient drills that allowed farmers to seed even larger tracts in a single day.

Recent improvements to drills allow seed-drilling without prior tilling or otherwise preparing the soil. This means that soils subject to erosion or moisture loss are protected until the seed germinates and grows enough to keep the soil in place.

Drilling

The term used for the mechanised sowing of an agricultural crop.

The seed from the hopper of a seed drill is distributed by a seed metering mechanism into a set of tubes arranged to provide a suitable distance between each other to allow optimum growth of the resulting plants. The seed falls into "drills", or channels made by a coulter.

Notes

References

*"The Genius of China", Robert Temple, ISBN 1853752924
*History Channel, "Where Did It Come From?" "Episode: Ancient China: Agriculture"

ee also

*Planter (farm implement)

External links

* [http://www.tiscali.co.uk/reference/encyclopaedia/hutchinson/m0006239.html Tiscali encyclopedia article on seed drills]
* [http://www.fao.org/ag/ags/agse/3ero/harare/PartII/27Choud.htm Conservation tillage]
* [http://www.pakissan.com/english/newtech/use.of.water.shtml Zero Tillage seed drilling in Pakistan]