The "Doku-utsugi" (Coriaria japonica) belongs to the family Coriariaceae. It is a small decidous tree that is endemic to Japan, and distributed northward from Kinki district of Honshu to Hokkaido. This tree grows in montane stream edges and screes, and can reach about 1.5 m in height. The leaves are long-ovate and opposite, and resemble to pinnately compound with 15-18 pairs of leaflets. It is a monoecious. The racemes are born on the axils of new branches, and the small flowers bloom from April to May. The fruits ripen rose pink to blackkish purple from August to September. All parts of plants contain poisonous coriamyrtin, in particular the fruits contain concentrated toxic components. It causes fatal poisoning after accidental eating of the plants.