Bromus inermis Leysser ssp. inermis

Family: Poaceae, Tribe: Bromeae

Pertinent Synonyms & Notes (particularly those used in California; go to GRIN for other synonyms)


Pertinent Common Names (particularly those used in California; go to GRIN for other common names)

smooth brome

Primary Disseminule Type


Description (diagnostics are in brown)

Spikelets solitary, pedicelled, consisting of 6–13 fertile florets with similar-looking though diminished sterile florets at apex, oblong, nearly terete, 15–25(40) mm long x 3–5 mm wide, glabrous or minutely scabrous, disarticulating below each fertile floret at maturity.

Glumes persistent, shorter than spikelet, membranous, without keel. Lower glume lanceolate, (4)6–9 mm long, 0.75 length of upper glume, 1(3)-veined (lateral veins typically absent), apex obtuse. Upper glume lanceolate, 6–11 mm long, same length as adjacent fertile lemma, 3-veined, apex obtuse.

Fertile florets: rachilla persistent, hairy or scabrid, callus short, blunt, glabrous.

Lemma oblong to elliptic, 8–13 mm long x 1.5–3 mm wide, with green or purple coloring, chartaceous, much thinner on margins, with rounded back (no keel), 5–7-veined, midvein and lateral veins ribbed, surface sometimes scabrous, glabrous or pubescent, hairy below, apex rounded to obtuse, entire to minutely bifid, awnless or awn subapical, delicate, short (up to 3 mm long).

Palea same length as lemma, keels ciliolate, surface glabrous or pubescent.

Caryopsis fusiform to elliptic, 6–7.5 mm long x 1.5–2 mm wide, brown, apex fleshy and hairy, dorsal side with a distinct longitudinal groove, hilum a prominent linear groove, same length as caryopsis.

Similar Species

Similar Species Comparison Chart

Risk Assessment (codes in yellow or red indicate cause for concern; assessments are current as of mid-2011; click AUQP, NZBORIC, or NZBPI for access to the most recent versions of these databases and possible assessment changes)