Schoenoplectus mucronatus (syn. Scirpus mucronatus) is a species of flowering plant in the sedge family known by the common names bog bulrush, rough-seed bulrush, and ricefield bulrush. It is native to Eurasia and Africa it is known on other continents as an introduced species and sometimes a weed. It is a weed of rice fields in California. It grows in moist and wet terrestrial habitat, and in shallow water. It is a perennial herb growing from a short, hard rhizome. The erect, three-angled stems grow in dense clumps and reach a meter tall. The leaves take the form of sheaths wrapped around the base of stem, but they generally do not have blades. The inflorescence is a headlike cluster of cone-shaped spikelets accompanied by an angled, stiff bract which may look like a continuation of the s