Hu Zhang
Polygonum cuspidatum Sieb. et Zucc.
☯ TCM Properties
Clears Damp-Heat and Resolves Jaundice; Clears Heat and Resolves Toxicity; Invigorates Blood and Dispels Stasis; Alleviates Pain; Resolves Phlegm and Stops Cough; Promotes Bowel Movement
Western Herbalism Properties
Botanical Description
Reynoutria japonica (Polygonum cuspidatum, Fallopia japonica) is a large, vigorous rhizomatous perennial herb in the Polygonaceae, native to eastern Asia and notoriously invasive in much of Europe and North America. From a thick, deeply running, woody rhizome with bright orange-yellow interior, hollow stems rise 1-3 m tall, jointed and reddish-mottled like bamboo and conspicuously swollen at the nodes, each sheathed by a papery ochrea. The alternate leaves are broadly ovate with a truncate base and pointed tip, 5-15 cm long, glabrous. Small greenish-white to cream flowers are borne in slender, erect to nodding axillary panicles in late summer; plants are functionally dioecious. Fruits are small winged three-angled achenes. The dried rhizome and root, harvested in spring or autumn, are Hu Zhang.
Dosage
| Form | Amount | Frequency | Duration | Population | Notes |
|---|---|---|---|---|---|
| decoction | 6-15g | Daily | — | — | — |
Cultural & Historical Context
Traditional Chinese Uses
Hu Zhang (giant knotweed rhizome, Japanese knotweed) is a cool herb that invigorates Blood, clears Heat, promotes bile flow, and drains Dampness. It is used for Blood stagnation conditions including amenorrhea and traumatic injury, Damp-Heat patterns including jaundice and urinary infections, and Lung Heat cough with phlegm. Modern research has extensively studied its active compound resveratrol for cardiovascular and anti-inflammatory effects. Its broad Blood-moving and Heat-clearing profile gives it wide clinical applicability.
Traditional American Uses
None Documented
Important Disclaimer
This information is for educational purposes only and is not intended to replace professional medical advice. Always consult a qualified healthcare provider before using any herbal remedy, especially if you are pregnant, nursing, or taking medications.