Calflora, a 501c3 non-profit
Distribution by County   1145    
Brassica rapa  L.
Common mustard, Field mustard, Rape mustard
Brassica rapa is an annual herb that is not native to California.
Cal-IPC rating: limited
Record Count by County

Alameda: 48 Kern: 1 Orange: 75 Santa Cruz: 41
Alpine: 2 Kings: 2 Placer: 15 Shasta: 9
Amador: 8 Lake: 15 Plumas: 24 Siskiyou: 99
Butte: 63 Los Angeles: 92 Riverside: 24 Solano: 31
Calaveras: 13 Madera: 2 Sacramento: 39 Sonoma: 55
Colusa: 8 Marin: 107 San Benito: 23 Stanislaus: 17
Contra Costa: 53 Mariposa: 28 San Bernardino: 12 Sutter: 22
Del Norte: 11 Mendocino: 21 San Diego: 100 Tehama: 8
El Dorado: 10 Merced: 25 San Francisco: 58 Trinity: 5
Fresno: 18 Modoc: 7 San Joaquin: 29 Tulare: 22
Glenn: 2 Mono: 2 San Luis Obispo: 73 Tuolumne: 10
Humboldt: 58 Monterey: 121 San Mateo: 165 Ventura: 29
Imperial: 1 Napa: 16 Santa Barbara: 82 Yolo: 25
Inyo: 1 Nevada: 11 Santa Clara: 158 Yuba: 13

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: 03/06/2026).