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. HaplomesUC.
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.
