Cortex Eucommiae. Part used: Bark. Known as Eucommia Bark. Entering meridians: Kidney and Liver. Origin: Guizhou, Sichuan and Shaanxi. Du Zhong may be able to tonify liver and kidneys, strengthen tendons and bones and prevent abortion. All Phoenix Medicial dry herb and concentrated herbal granules are grown without sulphur, pesticides or herbicides and are grown in the place of origin.