Carex aequialta
Carex aequialta is a tussock-forming perennial in the family Cyperaceae, that is native to China, Japan and Korea. It's common name in Korean is 물꼬리사초 or Mul-kko-ri-sa-cho. Description 
The perennial herb typically grows to a height of  and has short rhizomes and trigonous shaped culms with a length of . The basal leaves are brown and scalelike. There are also cauline leaves. The inflorescence is corymb-like with 2 to 4 spikes. The terminal spikes are 1.5 to 4.5 centimeters long, and awnless. There are 2 to 3 lateral spikes which are between 1.5 to 5 long. The perigynia are obovate, wide, and smooth. The achenes are suborbicular are 2 to 2.5 millimeters long. See also
 List of Carex species

References

aequialta
Plants described in 1909
Taxa named by Georg Kükenthal
Flora of China
Flora of Japan
Flora of Korea