Astragalus is valued for its tonic and adaptogenic effects. Astragalus is one of the most popular herbs in China today. Astragalus is native to northern China and the elevated regions of the Chinese provinces, Yunnan and Sichuan. The portion of the plant used medicinally is the four- to seven-year-old dried root, collected in the spring. While over 2,000 types of astragalus exist worldwide, the Chinese version has been extensively tested, both chemically and pharmacologically.