2. Chinese yam, the name of Chinese herbal medicine. This product is the dried rhizome of Dioscorea zingiberensis. 11~1February, cut off the roots, wash the soil, scrape off the skin with a bamboo knife, and dry it in the sun or dry it, which is the hairy yam. Choose coarse Chinese yam, soak it in clear water, add a little heat, cover it with a quilt, keep it moist and stuffy, then put it on a board and knead it into a cylinder, cut both ends together, dry it in the sun and polish it, which is the bright Chinese yam. The main functions are: invigorating spleen, tonifying lung, consolidating kidney and benefiting essence. Treat diarrhea due to spleen deficiency, chronic dysentery, cough due to fatigue, thirst quenching, nocturnal emission, leukorrhagia and frequent urination. Tonifying spleen and stomach, promoting fluid production and benefiting lung, tonifying kidney and astringent essence.