Avena sativa, the common oat (generally referred to as oats), is an annual member of grass family Poaceae and one of the eight major cereal crops of the world. (Cereals are a type of fruit called a caryopsis, composed of endosperm, germ, and bran; other major cereal crops are wheat [Triticum spp.], rice [Oryza sativa], barley [Hordeum vulgare], maize [Zea mays], and rye [Secale cereale].)
A. sativa no longer occurs in the wild, but related species of Avena occur in Europe and the Fertile Crescent region of the Near East. Cultivation appears to have started roughly 2,000 years ago during the Bronze Age in Celtic and Germanic regions of Europe, and emanated to other temperate and cold regions (Hedrick 1919). Oats are grown in temperate regions worldwide, with a 2009 total harvest of 23.3 million tons produced on 10.2 million hectares; leading producers are the Russian Federation, Canada, and the U.S. (FAOSTAT 2011). Total area cultivated with oats has declined since 1950 (IndexMundi 2011), with a concurrent increase in soybeans (Glycine max).
Oats are used as food for humans, in oatmeal (porridge), cereals, and cookies. Oats were long considered an inferior food: Samuel Johnson is said to have written, in his dictionary definition, oats were "eaten by people in Scotland, but fit only for horses in England" (to which a Scotsman retorted, "That's why England has such good horses, and Scotland has such fine men!" [Gibson and Benson 2002]). However, oats have increased in popularity in recent decades with research on health benefits of soluble fiber and with increasing numbers of people intolerant to wheat. Oats are high in soluble fiber, carbohydrates, and protein, and are a good source of magnesium, iron, and panthothenic acid (Wikipedia 2011).
Notwithstanding the increasing popularity as a health food, oats are primarily used for animal feed and fodder. They are commonly fed to horses and cattle, and are used in chicken feed and dog food. Oats are also used for pasture, hay, and sileage, and the straw is used as animal bedding (Magness et al. 1971).