Typical varieties are Scirpus acutus (hardstem bulrush), common tule, Scirpus cypernius (wool grass), Scirpus fluviatilis (river bulrush), Scirpus robustus (alkali bulrush), Scirpus validus (soft stem bulrush), and Scirpus lacustris (bulrush). Bulrush is known as Scirpus in the United States but is referred to as Schoeno-plectus in the rest of the world (Mitsch and Gosselink, 2000). Distribution is worldwide. Optimum pH is 4 to 9. Salinity tolerance for hardstem, wool grass, river, and soft stem bulrushes is 0 to 5 ppt; alkali and Olney's, 25 ppt. Growth of alkali, wool grass, and river bulrush is moderate, with dense cover achieved in 1 yr with 1-ft (0.3-m) plant spacing; growth of all others is moderate to rapid, with dense cover achieved in 1 yr with 1- to 2-ft (0.3- to 0.60-m) plant spacing. Deep root penetration in gravel is approximately 2 ft (0.6m). Annual yield is approximately 9 (dw) ton/ac (20 mt/ha). Tissue (dw basis) is approximately 18% N, 2% P; 30% solids. Bulrush seeds and rhizomes are a food source for many water birds, muskrats, nutria, and fish; they also provide a nesting area for fish when inundated. Bulrushes can be permanently inundated — hardstem up to 3 ft (1 m), most others 0.5 to 1 ft (0.15 to 0.3 m); some can tolerate drought conditions. They are commonly used for many FWS and SSF constructed wetlands in the United States.

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