Abstract: The species of alfalfa that existed in ancient China is unclear, because the color of its flowers was not recorded in any of the ancient texts. At present, there are five theories about the species of alfalfa in ancient China: 1) It was Medicago sativa; 2) it was Medicago hispida; 3) it was both M. sativa and M. hispida; 4) it was Medicago falcata; 5) the species is uncertain. On the basis of a critical evaluation of the alfalfa phytobiology literature and modern research findings, we speculate about the origin of alfalfa species in China. The results showed that alfalfa spread throughout China from Dayuan, consistent with the records of M. sativa introduction. Han E wrote in Sishi Zhuanyao in the Tang dynasty that the origin of the alfalfa species with purple flowers distributed along the yellow river was the same as that of the alfalfa referred to during the Han dynasty. After that, many texts recorded alfalfa with purple flowers and even its ecological and biological characteristics. It can be concluded that the alfalfa species naturalized in the Han dynasty had purple flowers, so it was M. sativa. Mei Yaochen in the Song dynasty and Li Shizhen in the Ming dynasty mentioned alfalfa with yellow flowers, indicating that yellow-flowered alfalfa existed and was utilized in China in the Song and Ming dynasties. According to the records in the Illustrated Catalogue of Plants, three alfalfa species (M. sativa, M. hispida, and M. falcata) were grown in ancient China.

Key words: alfalfa, species, ancient, Medicago sativa, Medicago falcata, Medicago hispida