ミズキ科ハナイカダ属の落葉低木で、学名は Helwingia japonica。英名は Japan helwingia。
The Japan helwingia (Helwingia japonica) belongs to Cornaceae (the Dogwood family). It is a small deciduous tree that is native to Japan, the Korean Peninsula and China. This tree grows in wettish forest edges and forest floors, and can reach 1-2 m in height. The leaves are oblong and opposite with aristate toothed edges. The pale green, four-petaled flowers bloom on the center of midribs from April to May. It is dioecious. The several male flowers are borne in a cluster and the female flower is usually alone. The fruits ripen into black from July to August, and they are sweet and edible. The burgeons are uesd for wild vegetable in Japan. The Japanese name comes from the appearance of the flowers and fruits on the leaves like raftsman. It is also called "青莢葉" (qing jia ye) in Chinese.