Bulbous Oat Grass

Appearance

This coarse grass can grow to 150 centimeters tall. The leaves are bright green, broad, slightly hairy, and rough. The ligule is 3 centimeters long and smooth edged. The panicle is up to 30 centimeters, and the bunched spikelets have projecting and angled awns up to 17 millimeters 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.

Naming

Two subspecies have been described:
⤷  "Arrhenatherum elatius" subsp. "elatius", the more common variety.
⤷  "Arrhenatherum elatius" subsp. "bulbosum", 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.

Distribution

It is native to Europe but 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 and fodder.

Habitat

"Arrhenatherum elatius" is a principal species in two UK National Vegetation Classification habitat communities: the very widespread MG1 and the much rarer MG2. This means that it can be found with species such as "Dactylis glomerata", and "Filipendula ulmaria".

It is found on road verges, along hedges and riverbanks.

It can colonise and stabilise limestone scree, bare calcareous cliffs, maritime shingle and coastal dunes.