Species in the genus Carex:

Carex deckinsii / Kouboumugi オニスゲ

Carex deckinsi, a perennial, 20-50cm in height, occurs in flatland wetlands and propagates itself by extending long its suckers, the branches of the underground runner. Leaves are 4-8mm in width, linear. In May-July, stems set flowers, male on the top and female beneath, and the fruit matures in late summer. Bloom time: May-July.