ロウバイ科ロウバイ属の落葉低木で、学名は Chimonanthus praecox f. concolor (syn. Chimonanthus praecox f. lutea)。英名は Wintersweet。
The Wintersweet (Chimonanthus praecox f. concolor) belongs to Chimonanthus (the Wintersweet family). It is a small deciduous tree that is native to China. This tree was introduced into Japan in the Meiji Era (1868-1912). It is a form of Wintersweet (Chimonanthus praecox) and it can reach 2-5 m in height. Leaves are ovate to oblong and oppposite. Fragrant ceroplastics-like pale yellow flowers come from December to February before foliation. The tepal is pale yellow both on outside and inside. In China, it does not seem to be distinguished from "Wintersweet" and both are called "蠟梅" (la mei)".