Bromus inermis is a perennial C3 grass (Reich et al. 2003), 0.5 to 1 m tall, cool season grass, sod-forming, colonial from rhizomes, plants hairless, except often finely hairy at nodes; sheaths closed near top; ligule to 0.1 cm.
Leaves alternate, blades 0.8-1.5 cm wide, to 30 cm long.
Flower spikelets about as long as inflorescence branches, 1.5-3 cm, 7-11 flowered; first glume 0.4-0.8 cm, second to 1cm; lemmas 1-1.2 cm, with little or no awns; self incompatible; inflorescence 10-20 cm long, at first open then contracted, branched, with stiff, open or ascending branches, 4-10 branches per node; blooming and fruiting June-July.
Wetland status: NL.
Frequency in NYC: Infrequent.
Habitat: Roadsides, open areas. Moderately tolerant of salt, tolerant of drought, intolerant of shade.
Notes: Seeds eaten by Itonidid midges and Chalcid flies as well as birds and small mammals (Sather, 1995; Martin et al. 1951).