Ricefield bulrush (Scirpus mucronatus)
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Ricefield bulrush, a perennial sedge, is widely distributed in California rice fields and other disturbed wet places, where it behaves like an annual. It can be found in the Sacramento Valley, San Francisco Bay region, western North Coast Ranges, and South Coast, up to an elevation of about 490 feet (150 m).
The mature plant is about 2 to 3 feet (60–90 cm) tall and generally shorter than river bulrush.
A single leaflike structure (bract) under the flower head distinguishes ricefield bulrush from river bulrush, which has three to five bracts. Ricefield bulrush also flowers later in the season than river bulrush, Scirpus fluviatilis, about 60 to 70 days after flooding.
Ricefield bulrush reproduces by seed and underground horizontal stems (rhizomes).