Isatis indigotica is the spacial Chinese herb from the plant that is commonly called Dyer's Woad. Banlangen is the name in Mandarin Pinyin. This is used in formulas relating to the winter time. It is commonly used in combination with the above ground part of the plant to make Chinese Herbal Tea. Both below ground and above ground parts make the full benefit, combined and cooked together. Sold by the pound. USA shipping only. No sales out of the USA. Use as directed by your Traditional Chinese Medicine Doctor. Limit servings to adults unless directed by your practitioner.