Avena fatua is a species of grass in the oat genus. It is known as the common wild oat. Like fellow wild oat species A. sterilis, it bears 42 chromosomes, and its seeds shatter at maturity for yearly seeding. This oat is native to Eurasia but it has been introduced to most of the other temperate regions of the world. It is naturalized in some areas and considered a noxious weed in others.