It is an annual grass growing 30 to 70 centimetres (12 to 28 in) tall with an open, branching inflorescence in the form of a panicle.

Both upper and lower glumes are lanceolate, and both are hairless or only have very fine hairs.

[3] Its anthers are about 0.4 mm (1⁄32 in) long, which suggests that most of its seeds are produced by self-fertilization.

[4] Bromus arizonicus is native to the American southwest and northwestern Mexico, occurring in the United States from California and Nevada east to Texas, and in Mexico in Baja California.

[2] It prefers dry, open areas and disturbed grounds at elevations lower than 2,000 m (6,600 ft) feet.