"Abukuma-toranoo" (Bistorta abukumensis) belongs to the Polygonaceae (the Knotweed family). It is a perennial herb that is distributed on the Pacific side of the Abukuma mountain range, from southern part of Miyagi prefecture to eastern southern part of Fukushima prefecture in Honshu. This herb grows on the forest floors along the mountain streams, and up to a height of 15-30 cm. It has bisexual and female plant. The basal leaves are elliptic, with acute tips, cordate bases and long petioles. The cauline leaves are ovate to elliptic, the lower leaves have a petiole, the upper leaves are sessile and enfold stem widely. The white or slightly reddish flowers will bloom in the raceme of the shoot apex from April to May. It is characterized by long peduncles, 3-7.5 mm.