Polygonum bistortoides Calflora

Distribution by County 6741

Polygonum bistortoides Pursh

(not an active name)

American bistort, Snakeweed, Western bistort, Western knotweed

Polygonum bistortoides is a perennial herb that is native to California, and also found elsewhere in North America and beyond.

also called Bistorta bistortoides

Record Count by County


Alpine: 37	Humboldt: 29	Modoc: 33	Siskiyou: 87
Amador: 1	Inyo: 1	Mono: 57	Solano: 3
Butte: 29	Kern: 1	Nevada: 62	Sonoma: 1
Calaveras: 1	Lake: 1	Placer: 48	Stanislaus: 1
Colusa: 2	Lassen: 34	Plumas: 45	Tehama: 20
Del Norte: 8	Madera: 17	Riverside: 18	Trinity: 35
El Dorado: 59	Marin: 9	San Bernardino: 35	Tulare: 86
Fresno: 72	Mariposa: 82	Shasta: 12	Tuolumne: 93
Glenn: 9	Mendocino: 10	Sierra: 65

Suggested Citation

Calflora: Information on California plants for education, research and conservation, with data contributed by public and private institutions and individuals, including the Consortium of California Herbaria. [web application]. 2026. The Calflora Database [a non-profit organization]. Available: https://www.calflora.org/ (Accessed: 01/15/2026).