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crop rotation
crop rotation The practice of growing different crops in different years on the same land, in order to prevent the soil's nutrients from being exhausted and to reduce the risk of a build-up of diseases and pests specific to one crop. Crop rotation was widespread in Europe from the time of the ROMAN EMPIRE. Two-field rotation was practised by the ancient Greeks: one half of a farmer's land was planted in the spring or autumn of each year, while the other half was left fallow (i.e. not planted with crops), to allow the soil to ‘rest’. The Romans developed the three-course rotation, which was in use from the Middle Ages until the 18th century. A three-year cycle was followed on each of three fields, with an autumn-sown crop such as rye or winter wheat, a spring-sown crop such as oats or beans, and a year of lying fallow. Two out of three fields were thus in cultivation every year. The three-field system succeeded only in countries with mild climates, such as England. With the AGRICULTURAL REVOLUTION and the acceleration of ENCLOSURES in the 18th century, more scientific methods were applied to crop rotation. A four-course rotation was adopted based on turnips, clover, barley, and wheat. The introduction of root-crops (such as turnips) improved the soil and hence the quality of harvest and livestock; they also smother the weeds that have grown between plants of the previous crop. The replacement of the fallow with a leguminous crop, such as clover, peas, beans, or lentils, boosts the fertility of the soil since leguminous plants are able to ‘fix’ atmospheric nitrogen, which enriches the soil when they die.
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Cite this article
"crop rotation." A Dictionary of World History. 2000. Encyclopedia.com. 10 Feb. 2012 <http://www.encyclopedia.com>. "crop rotation." A Dictionary of World History. 2000. Encyclopedia.com. (February 10, 2012). http://www.encyclopedia.com/doc/1O48-croprotation.html "crop rotation." A Dictionary of World History. 2000. Retrieved February 10, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O48-croprotation.html |
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crop rotation
crop rotation An agricultural practice in which different crops are cultivated in succession on the same area of land over a period of time so as to maintain soil fertility and reduce the adverse effects of pests. Legumes are important in the rotation as they are a source of nitrogen for the soil (see nitrogen fixation; root nodule). In the UK, other crops that may be included in a typical four-stage rotation are wheat, barley, and root crops. However, the use of pesticides enables the monoculture of crops in modern farming systems (see agriculture).
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Cite this article
"crop rotation." A Dictionary of Biology. 2004. Encyclopedia.com. 10 Feb. 2012 <http://www.encyclopedia.com>. "crop rotation." A Dictionary of Biology. 2004. Encyclopedia.com. (February 10, 2012). http://www.encyclopedia.com/doc/1O6-croprotation.html "crop rotation." A Dictionary of Biology. 2004. Retrieved February 10, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O6-croprotation.html |
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crop rotation
crop rotation Practice of successively growing different crops on the same field. Rotated crops generally complement each other, each providing nutrients required by the others.
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Cite this article
"crop rotation." World Encyclopedia. 2005. Encyclopedia.com. 10 Feb. 2012 <http://www.encyclopedia.com>. "crop rotation." World Encyclopedia. 2005. Encyclopedia.com. (February 10, 2012). http://www.encyclopedia.com/doc/1O142-croprotation.html "crop rotation." World Encyclopedia. 2005. Retrieved February 10, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O142-croprotation.html |
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