OBJECTIVETo identify Radix Scutellariae (Huangqin) of different growth years, to distinguish whether it's wild or cultivated and to provide useful information for the quality control of Huangqin crude drug.

METHODBy using morphological and histological methods, we studied 87 individuals of 45 specimens from 12 habitats of 5 provinces of China, which grew wild or were cultivated in different growing years. Moreover, 22 commercial samples of Huangqin from 7 provinces were also investigated.

RESULTThe identification was performed base on morphological and histological characteristics, such as, the shape, color, cork, remaining stems, decayed central xylem, and vessels arrangement, xylem cork ring, growth rings, etc.

CONCLUSIONWe established an identification method for distinguishing Huangqin wild or cultivated in different growing years. Furthermore, the structure of annual rings in the transection of Radix Scutellariae has been discovered for the first time.