Spikelets 2 per node . Florets 2 per spikelet , the upper much reduced and sterile. Awns and glumes flattened, stiff, with minute upward pointing barbs lining margins. Spikelets separate from the head above glumes. Old spikes consisting of the ascending glumes remain intact for a long period.
Some florets can remain attached to spikes long after plants turn brown.
Disturbed sites, grassland, openings in chaparral, oak woodlands, agronomic fields. Grows best on clay soils or where deep soil moisture is available late in the growing season. Seed production is prolific. Seeds disperse locally with wind and water and to greater distances with soil movement, human activities, and by clinging to the feet and fur of animals. Most seeds germinate in fall after the first rain, but some seeds remain dormant or germinate in winter or spring.