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Distribution by County   3022    
Equisetum arvense  L.
Common horsetail rush, Common horsetail, field horsetail, Field horsetail
Equisetum arvense is a fern that is native to California, and also found elsewhere in North America and beyond.
Record Count by County

Alameda: 25 Lake: 4 Plumas: 76 Sierra: 39
Alpine: 8 Lassen: 16 Riverside: 17 Siskiyou: 16
Amador: 3 Los Angeles: 16 Sacramento: 7 Solano: 6
Butte: 49 Madera: 8 San Benito: 2 Sonoma: 40
Calaveras: 8 Marin: 118 San Bernardino: 24 Sutter: 4
Colusa: 3 Mariposa: 34 San Diego: 40 Tehama: 31
Contra Costa: 7 Mendocino: 66 San Francisco: 2 Trinity: 28
Del Norte: 16 Modoc: 11 San Joaquin: 3 Tulare: 60
El Dorado: 46 Mono: 48 San Luis Obispo: 11 Tuolumne: 21
Fresno: 104 Monterey: 18 San Mateo: 51 Ventura: 17
Glenn: 1 Napa: 1 Santa Barbara: 11 Yolo: 1
Humboldt: 48 Nevada: 54 Santa Clara: 23 Yuba: 6
Inyo: 18 Orange: 34 Santa Cruz: 26
Kern: 11 Placer: 46 Shasta: 34

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: 06/14/2026).