The oat (Avena sativa), sometimes called the common oat, is a species of cereal grass (Avena) grown for fodder and for its seed, which is known by the same name (usually in the plural). Oats appear to have been domesticated as a secondary crop, as their seeds resembled those of other cereals closely enough for them to be included by early cultivators. Oats tolerate cold winters less well than cereals such as wheat, barley, and rye, but need less summer heat and more rain, making them important in areas such as Northwest Europe that have cool, wet summers. They can tolerate low-nutrient and acid soils. Oats grow thickly and vigorously, allowing them to outcompete many weeds, and compared to other cereals are relatively free from diseases.
Oats are used for human consumption as oatmeal, including as steel cut oats or rolled oats. Global production is dominated by Canada and Russia; global trade is a small part of production, most of the grain being consumed within the producing countries. Oats are a nutrient-rich food associated with lower blood cholesterol and reduced risk of human heart disease when consumed regularly. One of the most common uses of oats is as livestock feed; the crop can also be grown as groundcover and ploughed in as a green manure.
Description
The oat is a tall stout grass, a member of the family Poaceae; it can grow to a height of 1.8 metres (5.9 ft). The leaves are long, narrow, and pointed, and grow upwards; they can be some 15 to 40 centimetres (5.9 to 15.7 in) in length, and around 5 to 15 millimetres (0.20 to 0.59 in) in width. Leaf blades emerge first from nodes in the stalk, then the sheath. New leaves grow upwards on nodes further from the ground, leaves on the old nodes gradually brown and wilt. Roots are fibrous, mostly in the uppermost 0.3 metres (0.98 ft) of the soil (though some may penetrate as deep as 1.5 metres (4.9 ft), and develop from a crown at the soil surface. When seeds are dense, they make only one or...
