Commercial grain farming is an extensive and mechanised form of agriculture. This is a development in the continental lands of the mid-latitudes, which were once roamed by nomadic herdsmen.
The continental position, well away from maritime influence, and the low precipitation (between 305 and 660 mm/12 and 26 inches) make crop cultivation a calculated risk. It was the invention of farm machinery which enabled farmers to cultivate grain on a large scale, and there is a marked specialisation in wheat monoculture in many areas. Communication with the outside world is mainly by railways and the bulk of the grain harvest is exported.