A cereal grass plant whose seeds are useful to humans. It is grown in nearly all cultivated areas of the temperate parts of the world, and is an important crop in Europe, North and South America, North Africa, much of Asia, and Australia. Barley is the most dependable cereal crop where drought, summer frost, and alkali soils are encountered. In the United States, barley is grown to some extent in 49 states, with the most important production areas in North Dakota, Montana, and California. Principal uses of barley grain are as livestock feed, for the production of barley malt, and as human food. It is also used in some areas for hay and silage.