Wall Barley - Hordeum murinum

20 to 60 cm tall. Leaves light green, flat and hairy with inflated sheaths. Bristly flower spikes may reach up to 10 cm in length, though often shorter.

Meadow Barley (Hordeum secalinum) and other Hordeum, including some rarely recorded alien species. 

Annual (unlike Meadow Barley, which is perennial and has tillers at flowering).  May be present in bare-ish patches in older grasslands, as well as waste places, roadsides, around lamp-posts and bins, etc.

Roadsides and waste ground.

June to July.

Annual.

Fairly common in the southern half of Britain at least.

Fairly common in Leicestershire and Rutland. In the 1979 Flora survey of Leicestershire it was found in 367 of the 617 tetrads.