"Oni-yabu-mao" (Boehmeria holosericea) belongs to Urticaceae (the Nettle family). It is a perennial herb that is distributed westward from Honshu to Shikoku, Kyushu of Japan, China and the Indo-China Peninsula. This herb grows in coastal wilderness and streambanks, and can reach 70-100 cm in height. The leaves are large ovate, thick with serrate edges, and arranged in opposite. The rear surfaces of leaves are covered with dense velvety hairs. The flowers come in August to October. The female clusters are globose and borne on the lower leaf axils, and the female clusters are spicate and borne on the upper leaf axils.