Arrhenatherum

Arrhenatherum is a genus of grasses, commonly known as oat grass, native to temperate regions of Europe and Asia. These perennial plants are part of the Poaceae family and are named for their resemblance to true oats.1

The genus Arrhenatherum includes about six to seven species of tall grasses. A notable species is tall oat grass (A. elatius), which has been introduced globally as a pasture grass and can be considered a weed in some areas. A variety of tall oat grass, onion couch (A. elatius, variety bulbosum), is known for its bulblike stems and is a noxious weed outside its native range.1

Arrhenatherum grasses are characterized by 2-flowered spikelets, with the first floret being staminate and awned. Some species are cultivated for forage and pasture.21