The Gooseneck loosestrife (Lysimachia clethroides) belongs to Primulaceae (the Primrose family). It is a perennial herb that is distributed throughout Japan, as well as the Korean Peninsula, China and the Indochina Peninsula. This herb grows in sunny fields, hillsides and mountains, and can reach 30-100 cm in height. The leaves are oblong to narrow-ovate with short petioles. The paniculate racemes are borne on the stem apices and bloom many white flowers from July to August. The Japanese name comes from the fact that the inflorescence droops in the shape of a tiger's tail. In Chinese, it is called "矮桃" (ai tao).