Spermatophytes (seed plants): Angiosperms (flowering plants): Eudicots: Core Eudicots: Rosids: Fabids: Malpighiales
WEAKLEY'S FLORA OF THE SOUTHEASTERN US (2/10/25):
Hypericum perforatum ssp. perforatum
FAMILY
Hypericaceae
Go to FSUS key
Dig deeper at SERNEC, a consortium of southeastern herbaria.
Check out EDDMapS.org to see where this has been reported.
Read more about European St. Johnswort at Vascular Plants of North Carolina.
SYNONYMOUS WITH
PLANTS NATIONAL DATABASE:
Hypericum perforatum
FAMILY
Clusiaceae
SYNONYMOUS WITH Floristic Synthesis of North America. BONAP (Kartesz, 2021)
Hypericum perforatum
SYNONYMOUS WITH Flora of North America north of Mexico, vol. 6 (2015)
Hypericum perforatum ssp. perforatum
SYNONYMOUS WITH VASCULAR FLORA OF THE CAROLINAS (Radford, Ahles, & Bell, 1968) 126-01-026:
Hypericum perforatum FAMILY Hypericaceae
SYNONYMOUS WITH Manual of the Southeastern Flora (Small, 1933, 1938)
Hypericum perforatum
COMMON NAME:
European St. Johnswort, Klamath-weed
To see larger pictures, click or hover over the thumbnails.
)
USDA-NRCS PLANTS Database / Britton, N.L., and A. Brown. 1913 pnd_hype_001_lvd
)
USDA / Selected Weeds of the US. 1970 swus_page_267
)
Tim Spira tpshperforatum2
June
)
Tim Spira tpshperforatum2_2
June
Leaves sessile, with translucent dots that look like "windows", per Wildflowers of Tennessee, the Ohio Valley, and the Southern Appalachians (Horn, Cathcart, Hemmerly, & Duhl, 2005).
)
JK Marlow jkm090707_010
July Avery County NC
The Roan Highlands
)
JK Marlow jkm090707_015
July Avery County NC
The Roan Highlands
Numerous flowers borne in a compound cyme, per Wildflowers of Tennessee, the Ohio Valley, and the Southern Appalachians (Horn, Cathcart, Hemmerly, & Duhl, 2005).
)
JK Marlow jkm090707_016
July Avery County NC
The Roan Highlands
Flowers 3/4"-1" wide, with black "stitching" on the margins of petals, per Wildflowers of the Southern Mountains (Smith, 1998).
)
JK Marlow jkm090707_020
July Avery County NC
The Roan Highlands
Five petals, to 0.4" long, black-dotted near the margin, per Wildflowers of Tennessee (Carman, 2005).
WEAKLEY'S FLORA OF THE SOUTHEASTERN US (2/10/25):
Hypericum perforatum ssp. perforatum
FAMILY
Hypericaceae
SYNONYMOUS WITH
PLANTS NATIONAL DATABASE:
Hypericum perforatum
FAMILY
Clusiaceae
SYNONYMOUS WITH
Floristic Synthesis of North America. BONAP (Kartesz, 2021)
Hypericum perforatum
SYNONYMOUS WITH
Flora of North America north of Mexico, vol. 6
Hypericum perforatum ssp. perforatum
SYNONYMOUS WITH
VASCULAR FLORA OF THE CAROLINAS (Radford, Ahles, & Bell, 1968) 126-01-026:
Hypericum perforatum
FAMILY
Hypericaceae
SYNONYMOUS WITH
Manual of the Southeastern Flora (Small, 1933, 1938)
Hypericum perforatum
725
Forb
Perennial
Habitat: Fields, pastures, roadsides, woodland borders, per Weakley's Flora
Non-native: Europe
Common (uncommon in Coastal Plain)
CLICK HERE to see a map, notes, and images from Weakley's Flora of the Southeastern US.
This plant may be causing problems in natural areas outside its native range, according to authorities such as:
LEAVES:
Simple
Herbaceous, with broad leaves, 3(4) locular capsules, stamens connate at base into 3 or 5 fascicles, leaves with translucent (but very few black) glands, and sepals and/or petals marked with black dots or lines
Opposite
FLOWER:
Summer/Fall
Yellow
Radially symmetrical
5 persistent sepals
5 petals
Superior ovary
Bisexual
FRUIT:
Summer/Fall
Capsule
TO LEARN MORE about this plant, look it up in a good book!
- Invasive Plants, Guide to Identification, Impacts and Control (Kaufman & Kaufman, 2007) p333
- Newcomb's Wildflower Guide (Newcomb, 1977) p268
- Wildflowers of the Atlantic Southeast (Cotterman, Waitt, & Weakley, 2019) p253
- Wildflowers of the Eastern United States (Duncan & Duncan, 1999) p050
- Wildflowers of Tennessee (Carman, 2005) p065
- Wildflowers of Tennessee, the Ohio Valley, and the Southern Appalachians (Horn, Cathcart, Hemmerly, & Duhl, 2005) p088
- Wildflowers & Plant Communities of the Southern Appalachian Mountains and Piedmont (Spira, 2011) p390
- Wildflowers of the Southern Mountains (Smith, 1998) p098
If a search such as "Carex leptalea var. leptalea" doesn't deliver the results you want, try "Carex leptalea".
Or, to minimize chances of a misspelling, try just "Carex le".
Less is more: If "pencil flower" doesn't deliver the results you want, try "pencil".