Prairie Grass - introduced (*Bromus catharticus)

Native to South America. Perennial. C3.

Family. Poaceae (Grass family).

Identification:

• it is a tall grass (to 1.5m)
• the flower cluster is a loose spray
• the glumes are shorter than the spikelets
• the spikelets have many close-packed lemmas
• the lemmas are unawned or shortly awned
• the spikelets are sideways compressed
• the leaves are flat
• the ligule, becoming torn, is up to 4mm long
• the glumes taper to a very short (to 0.3mm) awn
• the spikelets are neatly packed close together, alternating sides along the spikelet
• the lemmas may have short awns (to 4mm), and are strongly keeled (i.e have a central ridge, like that of a boat)
• the flowers are green at first, and colour to distinctive shades of brown and green.

Prairie Grass is a very common weed, usually growing with other weeds in disturbed places. The flowers with shades of green and brown are distinctive.

It is an environmental weed.

Bromos: a kind of oat; catharticus: a purging effect.

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