Arrhenatherum elatius

Outside of its native range it can be found elsewhere as an introduced species. It is found especially in prairies, at the side of roads and in uncultivated fields. The bulbous subspecies can be a weed of arable land. It is palatable grass for livestock and is used both as forage (pasture) and fodder (hay and silage).

Description

This coarse grass can grow to 1.80 m (6 ft) tall. The leaves are 4–10 mm (0–0 in) wide, bright green, broad, slightly hairy, and rough. The ligule is 1–3 mm (0–0 in) long and smooth edged. The panicle is up to 30 cm (12 in), and the bunched spikelets have projecting and angled awns up to 17 mm (1 in) long, green or purplish. The panicles often remain into winter. The spikelets are oblong or gaping. It flowers from June to September. The roots are yellow.

Four subspecies are currently accepted by Kew's Plants of the World:

• Arrhenatherum elatius subsp. elatius, the typical (nominate) subspecies.
• Arrhenatherum elatius subsp. bulbosum (syn. Arrhenatherum tuberosum), onion couch or tuber oat-grass, distinguished by the presence of corms at the base of the stem, by which it propagates. It occurs in vegetated shingle and arable land.
• Arrhenatherum elatius subsp. cypricola (Cyprus, endemic).
• Arrhenatherum elatius subsp. sardoum (western Mediterranean region).