Culms (5)10-40 cm. Ligules 3-10 mm; blades 2.5-11(20) cm long, 2.5-7.5 mm wide. Panicles 2-8 cm long, 0.9-3.2 cm wide; branches 1-2 cm, with a few scattered, whitish hairs. Fertile spikelets 2.6-4.2 mm; lower rachilla internodes about 1 mm, glabrous; upper rachilla internodes 1.4-2.2(2.6) mm, puberulent or glabrous, sometimes scabrous; glumes 2.6-4.2 mm, bisexual florets 2.4-3 mm, minutely bifid, teeth shorter than 0.2 mm, apices awned, awns 5-7.2 mm; anthers 0.4-0.7 mm; rudimentary florets 0.4-0.6 mm, awns 4-5(7) mm. Sterile spikelets 6-9 mm; lemmas 1-2 mm. Caryopses 1-2 mm. 2n = 14.
Calif., Ariz., Pacific Islands (Hawaii), Tex.
Lamarckia aurea grows on open ground, rocky hillsides, and in sandy soil, at elevations from sea level to 700 m. Within the Flora region, it is known only from the southwest. It is an attractive, but rather weedy species.