The three-field system is a regime of crop rotation in which a field is planted with one set of crops one year, a different set in the second year, and left fallow in the third year. A set of crops is rotated from one field to another. The technique was first used in China in the Eastern Zhou period, [1] and was adopted in Europe in the medieval period.
The three-field system lets farmers plant more crops and therefore increase production. Under this system, the arable land of an estate or village was divided into three large fields: one was planted in the autumn with winter wheat or rye; the second field was planted with other crops such as peas, lentils, or beans; and the third was left fallow (unplanted). Cereal crops deplete the ground of nitrogen, but legumes can fix nitrogen and so fertilize the soil. The fallow fields were soon overgrown with weeds and used for grazing farm animals. Their excrement fertilized that field's soil to regain its nutrients. Crop assignments were rotated every year, so each field segment would be planted for two out of every three years.
Previously a two-field system had been in place, with half the land being left fallow. In Europe, the change to a three-field system happened from the 9th century to the 11th century. [2] With more crops available to sell and agriculture dominating the economy at the time, the three-field system created a significant surplus and increased economic prosperity. [3]
The three-field system needed more plowing of land and its introduction coincided with the adoption of the moldboard plow. These parallel developments complemented each other and increased agricultural productivity. The legume crop needed summer rain to succeed, and so the three-field system was less successful around the Mediterranean. Oats for horse food could also be planted in the spring, which, combined with the adoption of horse collars and horseshoes, led to the replacement of oxen by horses for many farming tasks, with an associated increase in agricultural productivity and the nutrition available to the population. [4]
In his 1769 work Lehre vom Gyps als vorzueglich guten Dung zu allen Erd-Gewaechsen auf Aeckern und Wiesen, Hopfen- und Weinbergen, [5] Johann Friedrich Mayer was one of the first Germans to advocate for new ways of expanding beyond the medieval three-field.
Crop rotation is the practice of growing a series of different types of crops in the same area across a sequence of growing seasons. This practice reduces the reliance of crops on one set of nutrients, pest and weed pressure, along with the probability of developing resistant pests and weeds.
Intensive agriculture, also known as intensive farming, conventional, or industrial agriculture, is a type of agriculture, both of crop plants and of animals, with higher levels of input and output per unit of agricultural land area. It is characterized by a low fallow ratio, higher use of inputs such as capital, labour, agrochemicals and water, and higher crop yields per unit land area.
The British Agricultural Revolution, or Second Agricultural Revolution, was an unprecedented increase in agricultural production in Britain arising from increases in labor and land productivity between the mid-17th and late 19th centuries. Agricultural output grew faster than the population over the hundred-year period ending in 1770, and thereafter productivity remained among the highest in the world. This increase in the food supply contributed to the rapid growth of population in England and Wales, from 5.5 million in 1700 to over 9 million by 1801, though domestic production gave way increasingly to food imports in the 19th century as the population more than tripled to over 35 million.
Shifting cultivation is an agricultural system in which plots of land are cultivated temporarily, then abandoned while post-disturbance fallow vegetation is allowed to freely grow while the cultivator moves on to another plot. The period of cultivation is usually terminated when the soil shows signs of exhaustion or, more commonly, when the field is overrun by weeds. The period of time during which the field is cultivated is usually shorter than the period over which the land is allowed to regenerate by lying fallow.
In agriculture, rotational grazing, as opposed to continuous grazing, describes many systems of pasturing, whereby livestock are moved to portions of the pasture, called paddocks, while the other portions rest. Each paddock must provide all the needs of the livestock, such as food, water and sometimes shade and shelter. The approach often produces lower outputs than more intensive animal farming operations, but requires lower inputs, and therefore sometimes produces higher net farm income per animal.
Slash-and-burn agriculture is a farming method that involves the cutting and burning of plants in a forest or woodland to create a field called a swidden. The method begins by cutting down the trees and woody plants in an area. The downed vegetation, or "slash", is then left to dry, usually right before the rainiest part of the year. Then, the biomass is burned, resulting in a nutrient-rich layer of ash which makes the soil fertile, as well as temporarily eliminating weed and pest species. After about three to five years, the plot's productivity decreases due to depletion of nutrients along with weed and pest invasion, causing the farmers to abandon the field and move to a new area. The time it takes for a swidden to recover depends on the location and can be as little as five years to more than twenty years, after which the plot can be slashed and burned again, repeating the cycle. In Bangladesh and India, the practice is known as jhum or jhoom.
Legumes are plants in the family Fabaceae, or the fruit or seeds of such plants. When used as a dry grain for human consumption, the seeds are also called pulses. Legumes are grown agriculturally, primarily for human consumption, but also as livestock forage and silage, and as soil-enhancing green manure. Well-known legumes include beans, chickpeas, peanuts, lentils, lupins, mesquite, carob, tamarind, alfalfa, and clover. Legumes produce a botanically unique type of fruit – a simple dry fruit that develops from a simple carpel and usually dehisces on two sides.
In agriculture, a green manure is a crop specifically cultivated to be incorporated into the soil while still green. Typically, the green manure's biomass is incorporated with a plow or disk, as is often done with (brown) manure. The primary goal is to add organic matter to the soil for its benefits. Green manuring is often used with legume crops to add nitrogen to the soil for following crops, especially in organic farming, but is also used in conventional farming.
In agriculture, cover crops are plants that are planted to cover the soil rather than for the purpose of being harvested. Cover crops manage soil erosion, soil fertility, soil quality, water, weeds, pests, diseases, biodiversity and wildlife in an agroecosystem—an ecological system managed and shaped by humans. Cover crops can increase microbial activity in the soil, which has a positive effect on nitrogen availability, nitrogen uptake in target crops, and crop yields. Cover crops reduce water pollution risks and remove CO2 from the atmosphere. Cover crops may be an off-season crop planted after harvesting the cash crop. Cover crops are nurse crops in that they increase the survival of the main crop being harvested, and are often grown over the winter. In the United States, cover cropping may cost as much as $35 per acre.
In agriculture, polyculture is the practice of growing more than one crop species together in the same place at the same time, in contrast to monoculture, which had become the dominant approach in developed countries by 1950. Traditional examples include the intercropping of the Three Sisters, namely maize, beans, and squashes, by indigenous peoples of Central and North America, the rice-fish systems of Asia, and the complex mixed cropping systems of Nigeria.
No-till farming is an agricultural technique for growing crops or pasture without disturbing the soil through tillage. No-till farming decreases the amount of soil erosion tillage causes in certain soils, especially in sandy and dry soils on sloping terrain. Other possible benefits include an increase in the amount of water that infiltrates into the soil, soil retention of organic matter, and nutrient cycling. These methods may increase the amount and variety of life in and on the soil. While conventional no-tillage systems use herbicides to control weeds, organic systems use a combination of strategies, such as planting cover crops as mulch to suppress weeds.
Nutrient management is the science and practice directed to link soil, crop, weather, and hydrologic factors with cultural, irrigation, and soil and water conservation practices to achieve optimal nutrient use efficiency, crop yields, crop quality, and economic returns, while reducing off-site transport of nutrients (fertilizer) that may impact the environment. It involves matching a specific field soil, climate, and crop management conditions to rate, source, timing, and place of nutrient application.
In agriculture, monocropping is the practice of growing a single crop year after year on the same land. Maize, soybeans, and wheat are three common crops often monocropped. Monocropping is also referred to as continuous cropping, as in "continuous corn." Monocropping allows for farmers to have consistent crops throughout their entire farm. They can plant only the most profitable crop, use the same seed, pest control, machinery, and growing method on their entire farm, which may increase overall farm profitability.
Soil conservation is the prevention of loss of the topmost layer of the soil from erosion or prevention of reduced fertility caused by over usage, acidification, salinization or other chemical soil contamination.
Agriculture began independently in different parts of the globe, and included a diverse range of taxa. At least eleven separate regions of the Old and New World were involved as independent centers of origin. The development of agriculture about 12,000 years ago changed the way humans lived. They switched from nomadic hunter-gatherer lifestyles to permanent settlements and farming.
The Old Rotation is a soil fertility experiment on the Auburn University campus in Auburn, Alabama. The Old Rotation experiment, which started in 1896, is the third-oldest ongoing field crop experiment in the United States and the oldest continuous cotton experiment in the world. It was the first experiment to show that a cotton/legume crop rotation would allow soil to support a cotton crop indefinitely. The Old Rotation is listed on the National Register of Historic Places.
Agriculture in England is today intensive, highly mechanised, and efficient by European standards, producing about 60% of food needs with only 2% of the labour force. It contributes around 2% of GDP. Around two thirds of production is devoted to livestock, one third to arable crops. Agriculture is heavily subsidised by the European Union's Common Agricultural Policy.
Farming systems in India are strategically utilized, according to the locations where they are most suitable. The farming systems that significantly contribute to the agriculture of India are subsistence farming, organic farming, industrial farming. Regions throughout India differ in types of farming they use; some are based on horticulture, ley farming, agroforestry, and many more. Due to India's geographical location, certain parts experience different climates, thus affecting each region's agricultural productivity differently. India is very dependent on its monsoon cycle for large crop yields. India's agriculture has an extensive background which goes back to at least 9 thousand years. In India, in the alluvial plains of the Indus River in Pakistan, the old cities of Mohenjo-Daro and Harappa experienced an apparent establishment of an organized farming urban culture. That society, known as the Harappan or Indus civilization, flourished until shortly after 4000 BP; it was much more comprehensive than those of Egypt or Babylonia and appeared earlier than analogous societies in northern China. Currently, the country holds the second position in agricultural production in the world. In 2007, agriculture and other industries made up more than 16% of India's GDP. Despite the steady decline in agriculture's contribution to the country's GDP, agriculture is the biggest industry in the country and plays a key role in the socio-economic growth of the country. India is the second-largest producer of wheat, rice, cotton, sugarcane, silk, groundnuts, and dozens more. It is also the second biggest harvester of vegetables and fruit, representing 8.6% and 10.9% of overall production, respectively. The major fruits produced by India are mangoes, papayas, sapota, and bananas. India also has the biggest number of livestock in the world, holding 281 million. In 2008, the country housed the second largest number of cattle in the world with 175 million.
Convertible husbandry, also known as alternate husbandry or up-and-down husbandry, is a method of farming whereby strips of arable farmland were temporarily converted into grass pasture, known as leys. These remained under grass for up to 10 years before being ploughed under again, while some eventually became permanent pasturage. It was a process used during the 16th century through the 19th century by "which a higher proportion of land was used to support increasing numbers of livestock in many parts of England." Its adoption was an important component of the British Agricultural Revolution.
Agriculture in the Middle Ages describes the farming practices, crops, technology, and agricultural society and economy of Europe from the fall of the Western Roman Empire in 476 to approximately 1500. The Middle Ages are sometimes called the Medieval Age or Period. The Middle Ages are also divided into the Early, High, and Late Middle Ages. The early modern period followed the Middle Ages.