Yam is usually produced in Shanxi, Zhejiang, Jiangxi, Yunnan, Hebei, Hunan, Hubei, Shaanxi, Jiangsu, Guizhou, Sichuan and Shandong. The yam in Wenxian County is the best and can also be used as medicine. Yam can not only be eaten by people, but also has high nutritional value. Can be used for regulating chronic cough and preventing osteoporosis.

Shandong yam

The output of Shandong yam is relatively low, but the quality is very good. Its length is usually about 40 to 50 cm, which has the function of preventing blood lipid precipitation.

Hebei yam

Hebei with yam, the thickness is very symmetrical, generally about 50 cm long. Has the effects of strengthening body and bones, stimulating appetite, nourishing food, moistening lung and moistening dryness.

Zhejiang yam

Zhejiang yam is about a catty in 2 yuan. Can be used for treating cough due to lung deficiency, diarrhea due to spleen deficiency, quenching thirst, and promoting gastrointestinal peristalsis.

Hunan yam

The output of yam in Hunan is very high. 14 yuan Each kilogram of yam is rich in dietary fiber, which can promote gastrointestinal digestion and enhance gastrointestinal digestion and absorption.