The cosmopolitan bulrush (Bolboschoenus koshevnikovii) Cyperaceae (the Sedge family). It is a perennial herb that is native to all over Japan, the Korean Peninsula, China, Taiwan and Sakhalin. This herb grows in coastal wetlands and estuaries, paddy fields, and can reach 40-70 cm in height. It is smaller than "Uki-yagara" (Bolboschoenus fluviatilis ssp. yagara). The leaves are linear, 2-5 mm wide and usually gather at the base. The 1-6 spikelets are densely attached to the tip of the stem from July to October. The spikelets are ovate-shaped with a length of 8-15 mm.