Calflora, a 501c3 non-profit
Distribution by County   4312    
Hypericum perforatum  L.
Common st. johnswort,   Klamath weed,   Klamathweed
Hypericum perforatum is a perennial herb that is not native to California.
Cal-IPC rating: limited
Record Count by County

Alameda: 9 Lassen: 66 Riverside: 4 Siskiyou: 183
Alpine: 2 Los Angeles: 2 Sacramento: 222 Solano: 14
Amador: 118 Madera: 74 San Benito: 2 Sonoma: 544
Butte: 200 Marin: 95 San Bernardino: 1 Stanislaus: 3
Calaveras: 23 Mariposa: 476 San Diego: 20 Sutter: 3
Colusa: 2 Mendocino: 98 San Francisco: 2 Tehama: 122
Contra Costa: 8 Merced: 4 San Joaquin: 3 Trinity: 534
Del Norte: 44 Modoc: 62 San Luis Obispo: 10 Tulare: 1
El Dorado: 246 Monterey: 93 San Mateo: 92 Tuolumne: 312
Fresno: 12 Napa: 40 Santa Barbara: 1 Ventura: 1
Glenn: 24 Nevada: 133 Santa Clara: 35 Yolo: 1
Humboldt: 138 Orange: 1 Santa Cruz: 26 Yuba: 37
Kern: 5 Placer: 199 Shasta: 362
Lake: 45 Plumas: 89 Sierra: 59

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]. 2024. Berkeley, California: The Calflora Database [a non-profit organization]. Available: https://www.calflora.org/   (Accessed: 11/21/2024).