The Jointhead arthraxon (Arthraxon hispidus) belongs to Poaceae (the Grass family). It is an annual herb that is widely distributed in various parts of Asia including Japan. This herb grows on rice field linches and fields, and can reach 30-50 cm in height. The leaves are ovate. The Japanese name is derived from crucian carp-like shaped leaves. The long peduncles are borne at the tip of stems and produce several purplish-brown spikes palmately from September to November. It is also called "Kariyasu" in Hachijo Island, and used as a dyewood for traditional silk fabric "Ki-hachijo". It is called "藎草" in Taiwanese Chinese and "荩草" (jin cao) in Chinese. It is a C4 plant (Plants with C4-type photosynthesis).