Gymnanthemum extensum, also known as bitterleaf tree, Chinese: 展枝斑鸠菊zhan zhi ban jiu ju, Thai: หนานเฉาเหว่ยnan chao woei, is a species of flowering shrub of the family Asteraceae.[1] It is an up to 8 m shrub or small tree found naturally growing at 1,200 m (3,900 ft) to 2,100 m (6,900 ft) above sea level in open forests or thickets in slopes, valleys and by the roadside.[2]