Irrigation is the application of water to crops. The water may be diverted from a stream or pumped from a well. Irrigation is used during drought in humid areas, but is usual in arid climates. Irrigation is also used to suppress weeds in rice fields[1] and to protect plants against frost.[2]Agriculture that relies only on direct rainfall is referred to as rain-fed farming. Irrigation is often studied together with drainage, which is the natural or artificial removal of surface and sub-surface water.
Added by Fred Bauder
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