Bouteloua barbata

Bouteloua barbata Lag. (Poaceae), six-weeks grama or sixweeks grama, is a small tufted warm-season annual grass 5-30 cm tall, native to dry rangelands and disturbed ground of the southwestern United States and northern and central Mexico, where it is common on sandy, gravelly and clay soils in desert grassland, mesquite scrub and roadsides. The tufted base produces several geniculate, branched culms that often spread outward and root at the lower nodes. Leaves are short, with flat to involute blades 2-6 cm long and 1-2 mm wide and a fringed membranous ligule. The inflorescence consists of three to seven short pectinate, one-sided spikes 1-2 cm long, each held more or less at right angles to the culm and resembling a small comb or eyebrow, hence one of the common names. Each spike bears many densely crowded spikelets with conspicuous three-awned lemmas. It is a quick-growing post-rain annual that completes its life cycle in roughly six weeks under favorable conditions.