|common wild oat (Avena fatua)|
about 33, see text
Avena is a genus of 33 species (including two hybrids) in the grass family Poaceae. Collectively known as the oats, they include some species which have been cultivated for thousands of years as a food source for humans and livestock. They are widespread throughout Europe, Asia and northwest Africa. Several species have become naturalized in many parts of the world, and are regarded as invasive weeds where they compete with crop production. All oats have edible seeds, though they are small and hard to harvest in most species.
- See Oat for a more detailed discussion of the oat as a food source.
For diseases of oats, see List of oat diseases.
One species is of major commercial importance as a cereal grain. Four other species are grown as crops of minor or regional importance.
- Avena sativa – the common oat, a cereal crop of global importance and the species commonly referred to as "oats"
- Avena abyssinica – the Ethiopian oat, called "a half-weed, half-crop confined to the highlands of Ethiopia."
- Avena byzantina, a minor crop in the Near and Middle East
- Avena nuda – the naked oat or hulless oat, which plays much the same role in Europe as does A. abyssinica in Ethiopia. It is sometimes included in A. sativa and was widely grown in Europe before the latter replaced it. As its nutrient content is somewhat better than that of the common oat, A. nuda has increased in significance in recent years, especially in organic farming.
- Avena strigosa – the lopsided oat, bristle oat, or black oat, grown for fodder in parts of Western Europe and Brazil
These species, called wild oats or oat-grasses, are nuisance weeds in cereal crops, as, being grasses like the crop, they are difficult to remove chemically; any standard herbicide that would kill them would also damage the crop. A specific herbicide must be used. The costs of this herbicide and the length of time it must be used to reduce the weed is significant, with seeds able to lie dormant for approximately 10 years.
- Avena barbata – slender wild oat
- Avena brevis – short oat
- Avena fatua – common wild oat
- Avena maroccana – Moroccan oat
- Avena occidentalis – western oat
- Avena pubescens – downy oat-grass
- Avena pratensis – meadow oat-grass
- Avena spicata – poverty oat-grass
- Avena sterilis – winter wild oat
"Sowing wild oats" is a phrase used since at least the 16th century; it appears in a 1542 tract by Thomas Beccon, a Protestant clergyman from Norfolk. Apparently, a similar expression was used in Roman Republican times, possibly by Plautus. The origin of the expression is the fact that wild oats, notably A. fatua, are a major weed in oat farming. Among European cereal grains, oats are hardest to tell apart from their weedy relatives, which look almost alike but yield little grain. The life cycle of A. fatua is nearly synchronous with that of common oat, and their relationship is an example of Vavilovian mimicry. Historically, growers could control the weed only by checking the crop plants one by one and hand-weeding. Consequently, "sowing wild oats" became a phrase to describe unprofitable activities. Given the reputation of oat grain to have invigorating properties and the obvious connection between plant seeds and human "seed", it is not surprising that the meaning of the phrase became a reference to the destructive sexual liaisons of an unmarried young male, which result in unwanted children born out of wedlock.
|Wikimedia Commons has media related to Avena.|
- Quinion, Michael (1999): World Wide Words: Sow one's wild oats. Web posted 1999-NOV-27. Retrieved 2007-OCT-17.
- Zohary, Daniel & Hopf, Maria (2000): Domestication of plants in the Old World (3rd ed.). Oxford University Press.