"Inu-enju" (Maackia amurensis ssp. buergeri) belongs to Fabaceae (the Pea family). It is a tall deciduous tree that is endemic to Japan, and distributed northward from Chubu-district of Honsho to Hokkaido. This tree grows in forest edges or stream banks, and can reach about 15 m in height. The barks are grayish-brown and furrowed longitudially. The leaves are impari-pinnate with 7-13, ovate leaflets. The 3-7 racemes are borne on the terminal branches, and the pale yellowish-white, papilionacenous flowers bloom from July to August. The fruits are broad-linear seed pods, 4-9 cm long.