Ground elm is the root, herbaceous charcoal or raw use of the Rosaceae plant. The medicinal properties of ground elm charcoal are sour and astringent, and its effects are cooling the blood to stop bleeding, astringent to sores and detoxification. Diyu charcoal is commonly used clinically to treat the following diseases: 1. Treatment of various blood-heat and bleeding evidence. Because of its descending nature, Diyu charcoal is often used to treat bleeding in the lower jiao, such as blood in the stool, blood in urine, blood in hemorrhoids, and blood in collapses, etc. It is often used in combination with Bai Mao Root, Sheng Di, and Dan Pi, etc. 2. It can be used clinically to treat skin oozing, eczema, itching, canker sores and poisoning by pounding the fresh product.