Plants loosely cespitose, not rhizomatous. Culms 40–150 cm, glabrous, often branching at the lower cauline nodes; basal branching extravaginal. Leaves not basally concen-trated; sheaths glabrous, persis-tent; ligules of lower leaves 0.5–1.5 mm, truncate; ligules of upper leaves 1.5–4 mm, rounded to sharply acute; blades 5–30 cm long, 2–10 mm wide, flat, smooth on both surfaces. Panicles 10–40 cm, lax, lower nodes either with 3–7 branches bearing 10–40 functional spikelets, or with 15–30+ branches with no functional spikelets; primary branches spreading to ascending; lower branches 3–8 cm; secondary branchesdiverging from the primary branches. Glumes 2.5–3.5 mm, acuminate, 3-veined; florets 1.5–2 mm, dorsally compressed; calluses about 0.3 mm, glabrous, dis-articulation scars circular; lemmas stiffly membranous, glabrous, margins fused at the base, not overlapping, light brown at maturity; awns 3–4 mm; anthers 2–2.5 mm, penicillate; ovaries rounded, bearing two styles. Caryopses 1.5–1.7 mm long, about 0.8 mm thick; hila linear, about 1/2 as long as the caryopses. 2n = 24.
Piptatherum miliaceum is a Eurasian introduction that is now established in several parts of the world. In its native range it grows, often as a common species, primarily in disturbed areas, wadis, and oases, penetrating into the semidesert regions of northern Africa and western Asia. It is used as a fodder plant in northern Africa. Within the Flora region, P. miliaceum is known from Arizona and California, growing in disturbed sites. It has also been found on a ballast dump in Maryland.