Grows on many soil types, but is adapted to alkaline and saline soils with at least 5800 ppm of sodium chloride. Abundance depends on yearly rainfall amounts. Seeds disperse with wind, water, human activities, seed-gathering ants, animals, and when dry plants break off at ground level and tumble with the wind. Many seeds survive ingestion by animals, including sheep and rabbits. Plants produce 2 types of seed depending on photoperiod.
Experimental evidence suggests that the bract-like sepals enforce dormancy of brown seeds.
Cool moist vernalization appears to enhance germination of brown seeds by decomposing the adherent sepals. Plants typically produce more black seeds than brown, but the ratio varies according to environmental conditions. Most black seeds are shed by early November. Brown seeds may remain on plants until February. Most seeds germinate late fall to early spring in cold winter areas, but some germination can occur year round when conditions become favorable.