Duzhong is the bark from the eucommia tree, which can reach heights of up to 15 metres. The trees’ survival was once threatened because their bark was often stripped to the point of killing them. Today, harvesting is limited to peeling small patches from trees more than 10 years old in the late summer and early autumn. Duzhong is now expensive and not always easy to come by. It’s considered one of the noble herbal drugs in traditional Chinese medicine, with healing properties in the white, rubbery liquid of the inner bark. According to Li Shizhen’s Compendium of Materia Medica, the name duzhong derives from an old story about an man named Du Zhong, who took the herb and became enlightened. Duzhong has a warm nature and sweet taste. It’s said to be able to tone the liver and kidneys, strengthen tendons and bones, help calm a restless foetus to prevent miscarriage and lower blood pressure, among other things. It’s also taken to alleviate fatigue, impotence and lower back pain related to a kidney deficiency. Modern pharmacological studies suggest duzhong can be used as an anti-oxidative and an anti-inflammatory, to counter fatigue, reduce stress, synthesise collagen, heal wounds, and stimulate the immune system. Because duzhong has a warm nature, according to TCM, anyone who is yin-deficient should use it with caution. Signs of yin deficiency include hot flushes in the day or evening, weak, rapid nervous movements, night sweats, warm palms and soles, insomnia, dizziness and dark yellow urine. The dosage of duzhong in decoction and pill form is 10-15g. Dry-fried duzhong is more potent than the unprocessed form. Frying the bark with salt enhances its tonifying effects on the liver and kidneys by increasing the extraction of active ingredients. Salt-fried duzhong is is used to treat lower back pain. Before taking any medicine, consult your TCM or general practitioner Rose Tse and Angela Collingwood info@shen-nong.com Edited by Suzanne Harrison suzanne.harrison@scmp.com Published: January 23, 2006 Source: South China Morning Post