Japanese name: ミヤマタニワタシ（深山谷渡） Scientific name:Vicia bifolia
A perennial 30–70 cm tall, growing in forests in the mountains.
It has a slender rhizome.
The stem is erect, and its upper part zigzags at each node.
Leaves are alternate and even-pinnately compound with 2 leaflets; the tendrils are hardly developed.
The leaflets are narrowly ovate to ovate, 4–13 cm long and 1.5–4.5 cm wide, with a long, sharply pointed tip; they are thin in texture and slightly wrinkled.
The stipules are ovate to narrowly ovate and often have teeth at the base.
Short racemes 5–20 mm long arise from the upper leaf axils and bear 5–10 flowers.
The flowers have almost no flower stalks.
The flowers are bluish purple and 12–17 mm long; the bracts are narrowly ovate to ovate, 3–8 mm long, and remain after flowering.
The fruit is a flat legume that splits open when ripe.
