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Taxon  Report  
Hypericum perforatum  L.
Common st. johnswort,   Klamath weed,   Klamathweed
Hypericum perforatum is a perennial herb that is not native to California.
Cal-IPC rating: moderate
Siskiyou Del Norte Modoc Humboldt Shasta Lassen Trinity Plumas Tehama Butte Mendocino Glenn Sierra Yuba Lake Nevada Colusa Placer Sutter El Dorado Yolo Alpine Napa Sonoma Sacramento Mono Amador Solano Calaveras Tuolumne San Joaquin Marin Contra Costa Alameda Santa Cruz Mariposa Madera San Francisco San Mateo Merced Fresno Stanislaus Santa Clara Inyo San Benito Tulare Kings Monterey San Bernardino San Luis Obispo Kern Santa Barbara Ventura Los Angeles Riverside Orange San Diego Imperial
Observation Search
(3984 records)
redone or more occurrences
within a 7.5-minute quadrangle
bloom graphic
Bloom Period
Subspecies and Varieties:
Genus: Hypericum
Family: Hypericaceae  
(Clusiaceae)
Category: angiosperm  
PLANTS group:Dicot
Jepson eFlora section: eudicot

Wetlands: Occurs usually in non wetlands, occasionally in wetlands

Habitat: disturbed, disturbed

Communities: weed, characteristic of disturbed places

Name Status:
Accepted by PLANTS
Information about  Hypericum perforatum from other sources
USDA PLANTS Profile (HYPE)

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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]. 2023. Berkeley, California: The Calflora Database [a non-profit organization]. Available: https://www.calflora.org/   (Accessed: 02/07/2023).