Cornus
Cornus (shanzhuyu or shanyurou) is frequently used in Chinese herbal medicine as a tonic and astringent, mainly in formulas that nourish the liver and kidney. Perhaps the best known application of cornus is in Rehmannia Six Formula (Liuwei Dihuang Wan) and its many modifications.
The dried fruit is said to replenish the liver and kidney (referring to the yin essence) and restrain loss of essence. Indications for its use are internal wind syndromes associated with deficiency of liver, such as dizziness and tinnitus; symptoms of kidney qi deficiency, with soreness in the lower back and knees, impotence, frequent urination, and enuresis; and symptoms of uncontrolled discharge, such as excessive uterine bleeding, leukorrhea, or profuse sweating. It is considered slightly warm in nature, and is notably sour in taste. Although cornus is listed in the materia medica as an astringent, it rarely appears in formulas that are today classified as astringent formulas, appearing instead in tonic therapies. Typical dosage is 6-12 grams in decoction.