Purple price's feather (Amaranthus patulus) belongs to Amaranthaceae (the Amaranth family). It is an annual herb that is native to the tropical America. Nowadays, it is naturalized widely in Asia and Australia. It was introduced into Japan in the days of Meiji Era (about 160 years ago). This herb grows in grasslands, fields and waste grounds, and can reach 60-200 cm in height. The stems are erect, green and sometimes tinged rose pink. The leaves are diamond-ovate with long petioles. The mat magenta, slender and columnar spikes are borne from summer to fall. It is a discolored form of Smooth pigweed.