Tillage
From Wikipedia, the free encyclopedia
Tillage, or cultivation (a term which also has broader meanings related to the raising of plants in general) is the agricultural preparation of the soil by digging it up. Tillage can also mean the land that is tilled.
Primary tillage loosens the soil and mixes in fertilizer and/or plant material, resulting in soil with a rough texture. Secondary tillage produces finer soil and sometimes shapes the rows. It can be done by a using various combinations of equipment: plough, disk plough, harrow, dibble, hoe, rotary tillers, subsoiler, ridge or bed forming tillers, roller.
Weed plants (seeds, tubers, etc.) may be exhausted by repeated tilling. The weeds expend energy to reach the surface, and then get turned into the soil by tilling. The cycle is repeated until the weeds are dead.
Modern agricultural science has greatly reduced the use of tillage. Crops can be grown for several years without any tillage through the use of herbicides to control weeds, genetically modified crops that tolerate packed soil, and equipment that can plant seeds or fumigate the soil without really digging it up. This practice, called no-till farming, reduces costs and environmental change by reducing soil erosion and diesel fuel usage. Organic farming tends to require extensive tilling, as did most farming throughout history.
Tilling was first performed via human labor, sometimes involving slaves. Hoofed animals could also be used to till soil via trampling. The wooden plough was then invented. It could be pulled by mule, ox, elephant, water buffalo, or similar sturdy animal. Horses are generally unsuitable, though breeds such as the Clydesdale could work. The steel plough allowed farming in the American Midwest, where tough prarie grasses and rocks caused trouble. Soon after 1900, the farm tractor was introduced, which eventually made modern large-scale agriculture possible.
[edit] References
Brady, Nyle C., R.R. Weil (2002). The nature and property of soils, 13th edition. New Jersey: Prentice Hall. ISBN 0130167630.