Bian Xu
Polygonum aviculare L.
☯ TCM Properties
Clears Heat and Promotes Urination to Relieve Stranguria; Expels Parasites; Relieves Itching
Western Herbalism Properties
Botanical Description
Polygonum aviculare, common knotgrass or Bian Xu, is an annual herbaceous species in the Polygonaceae family with a near-cosmopolitan distribution on disturbed ground, paths, and field margins. Plants form prostrate to ascending mats 10-50 cm across, with slender, wiry, often reddish jointed stems bearing a characteristic silvery membranous ocrea at each node. Leaves are alternate, elliptic to lanceolate, 1-3 cm long, with entire margins. Tiny inconspicuous flowers 2-3 mm across, with greenish-white to pink-edged tepals, are borne singly or in small clusters in leaf axils from late spring to autumn, producing small triangular achenes.
Dosage
| Form | Amount | Frequency | Duration | Population | Notes |
|---|---|---|---|---|---|
| decoction | 9-15g | Daily | — | — | — |
Cultural & Historical Context
Traditional Chinese Uses
Bian Xu (knotgrass herb, polygonum aviculare) is a cool herb used in Chinese medicine to clear Damp-Heat from the Bladder, promote urination, and expel intestinal parasites. It is applied for urinary tract infections with burning and difficult urination from Damp-Heat, as well as for intestinal parasitic infections including roundworm and pinworm. Its anti-parasitic action differentiates it from many other diuretic herbs and gives it a dual role in Lower Burner Damp-Heat with concurrent parasite infestation.
Traditional American Uses
Polygonum aviculare is documented in the NAEB database with 20 medicinal (Drug) uses across Cherokee, Iroquois, Navajo (Ramah), Thompson, Choctaw, and Mendocino peoples. Recorded categories include pediatric aid, analgesic, antidiarrheal, dermatological aid, urinary aid, gynecological aid, orthopedic aid, and gastrointestinal aid applications, typically employing decoctions or infusions of the whole plant (NAEB).
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.