Culms 17-60 cm, geniculate to semiprostrate at the base, usually with several tillers. Sheaths with hyaline margins, lower cauline sheath margins usually ciliate; blades 1.5-7 cm long, 2-3 mm wide. Spikes 2.2-6 cm long, 0.4-0.5 cm wide, narrowly ellipsoid at the base, subcylindrical distally, with 2-7 fertile spikelets; rudimentary spikelets (2)3; disarticulation at the base of the spikes. Lower fertile spikelets 7-13 mm, lanceolate-ovate, with 3-5 florets, first 1-2 florets fertile; upper spikelets 7-9 mm, reduced. Glumes of lower spikelets 6-10 mm, 2-3-awned, awns 2.5-6 cm, glabrous, scabrous, or velutinous, if 3-awned the central awn often shorter than the lateral awns, sometimes reduced to a tooth; glumes of apical spikelets 6-8 mm, 3-awned, central awns 2.5-8 cm, longer than the lateral awns; lemmas 7-11 mm, with 2-3 teeth, if 3-toothed the central tooth the longest, sometimes extending into an up to 10 mm awn. Caryopses 5-8 mm, falling free from the lemmas and paleas. Haplomes UC. 2n = 28.

North American collections of Aegilops triuncialis are from disturbed sites, mostly roadsides and railroads, in California and western Nevada. The native range of the species extends from the Mediterranean area east to central Asia and south to Saudi Arabia. Specimens from the Flora region belong to Aegilops triuncialis var. triuncialis, which has apical spikelets with 5-8 cm central awns on the glumes and 2 well-developed 1-3 cm lateral awns, and lateral spikelets with 2-3 well-developed 1.5-6 cm awns. It differs from A. triuncialis var. persica (Boiss.) Eig, which has apical spikelets with 2-5 cm central awns on the glumes and 2 lateral awns of 1-2 cm, sometimes reduced to teeth, and lateral spikelets with 1 awn to 1.5 cm and 1-2 teeth.