Leaves are decussate, trifoliolate. Leaflets are dentate serrate, herbaceous.

Lateral veins raise beneath.

Petioles are slender, glabrous, reddish, enlarged at the base.

Flowers open densely in May to June on the shoot of previous year.

This species prefers moist soils along streams in the cooltemperate zone.

The wood is used for utensils, fuels.

Distribution ; Hokkaido, Honshu, Shikoku, Kyushu