Plants annual. Culms 10-40 cm, erect or ascending. Lower sheaths densely retrorsely villous-pubescent, upper sheaths glabrous; ligules 0.5-1.0 mm, glabrous, truncate, dentate or lacerate; blades 5-20 cm long, 1.5-4 mm wide, pilose, sparingly pubescent, or subglabrous. Panicles 6-15 cm long, 1-2 cm wide, racemose, dense, strongly contracted, stiffly erect; branches shorter than the spikelets, stiff, erect, straight. Spikelets 17-45 mm long, 4-7 mm wide, narrowly oblong or lanceolate, terete to moderately laterally compressed, usually 1 per node; florets (4)8-12, bases concealed at maturity; rachilla internodes concealed at maturity. Glumes glabrous or puberulent; lower glumes 7-9 mm, 3-veined, upper glumes 8-11 mm, 5-7-veined; lemmas 11-15(17) mm long, 3-5 mm wide, lanceolate, glabrous or pubescent, 9-veined, rounded over the midvein, margins bluntly angled, not inrolled at maturity, apices and teeth acuminate, teeth less than 1 mm; awns 12-20 mm, strongly divaricate at maturity, flattened and often basally twisted, arising 1.5 mm or more below the lemma apices; anthers 0.75-1.5 mm. Caryopses equaling or shorter than the paleas, thin, weakly inrolled or flat. 2n = 14, 28.

Bromus caroli-henrici is native to Mediterranean Europe. In the Flora region, it grows in open, disturbed areas in north-central California. It has been misidentified as B. alopecuros Poir., but differs mainly in having single spikelets at the nodes versus 2-3, and in its acuminate versus broadly triangular lemma teeth.