Taxon  Report   4312 
Hypericum perforatum  L.
Klamath weed,  Klamathweed, common St. Johnswort
Hypericum perforatum, a dicot, is a perennial herb that is not native to California; it was introduced from elsewhere and naturalized in the wild.
The California Invasive Plant Council classifies its potential impact on native ecosystems as moderate   (plant profile / CalWeedMapper).

 Interactive Distribution Map 

 Observation Hotline 
 (observation details + photos)

point, line, or polygon

one or more occurrences within a 7.5-minute quadrangle

 Plant Characteristics
 and Associations

Bloom Period
Hypericum perforatum
© 2003 Penn Martin II
Hypericum perforatum
© 2005 Louis-M. Landry
Hypericum perforatum
© 2005 Louis-M. Landry
weed, characteristic of disturbed places
Habitat: disturbed, disturbed [Walker]
Genus: Hypericum
Subspecies and Varieties:
Hypericum perforatum ssp. perforatum
Distribution by County 

Add an Observation of  Hypericum perforatum

Name Status:
Accepted by TJM2 + PLANTS + JM93
 Information about  Hypericum perforatum  from other sources:

Commercial availability unknown.

Photos on CalPhotos / Google Images

website references on Google

Jepson eFlora

Records from the Consortium of California Herbaria

Original Publication citation. on the
International Plants Names Index

Search (Flora of North America)

Hypericum perforatum
© 2007 Louis-M. Landry

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]. 2015. Berkeley, California: The Calflora Database [a non-profit organization].
Available:   (Accessed: Sep 04, 2015).

The information on this page comes from diverse sources. None of the links are sponsored.

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