Hypericum perforatum
Hypericum scouleri
Chase-devil, common St. John's-wort, Klamath weed, millepertuis commun, Tipton's weed
Norton's St. John's-wort, Scouler's St. John's-wort, western john's-wort, western St. John's-wort
internodes usually weakly 2-lined, sometimes not lined, without black glands, rarely with reddish glands.
usually spreading, rarely erect, sessile or (proximal) subpetiolate;
blade oblong-elliptic or elliptic to triangular-ovate or (proximal) obovate, 12–28(–32) × 6–15(–18) mm, base subcordate to rounded or (proximal) cuneate, margins plane, apex obtuse to rounded, midrib with 4–5 pairs of branches, tertiary veins not densely reticulate, black glands intramarginal (± dense) and, rarely, (1–2) laminar (distal).
cylindric to narrowly pyramidal, (1–)8–20-flowered.
6–15(–25) mm diam.;
sepals not or scarcely imbricate, erect in fruit, ovate to lanceolate or narrowly oblong, unequal to subequal, 2.5–5.5 × 1–2 mm, apex acute to rounded;
petals golden yellow, sometimes red-tinged, oblanceolate, 7–12 mm;
stamens 50–90(–109);
anther gland black;
styles 2–8 mm.
oblanceoloid, 6–10 × 3.5–6 mm, with longitudinal vittae.
not carinate, (0.5–)0.7–0.8 mm;
testa linear-reticulate.
= 16.
Hypericum perforatum
Hypericum scouleri
Subspecies 4 (1 in the flora).
Hypericum perforatum has been introduced into various parts of the world, including North America, where only subsp. perforatum is represented. The range of variation in the flora area is less than occurs in Europe, and signs of hybridization that are common there are absent in North America.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Some authors have included Hypericum scouleri in central Mexican H. formosum Kunth as a synonym, subspecies, or variety; the similarities in sepal form and glandularity between these species are due to convergence. Hypericum formosum is related to another Mexican species (H. oaxacanum R. Keller); the affinities of H. scouleri are with the H. attenuatum group from eastern Asia. Hypericum scouleri itself does occur in northern and central Mexico as far south as Michoacán, México, and Hidalgo, where it is known by the synonym H. simulans Rose.
J. M. Gillett and N. K. B. Robson (1981) treated the dwarf alpine form of Hypericum scouleri as subsp. nortoniae. Further work has revealed a range of intermediate forms between the two putative subspecies, which prevents their recognition. Likewise, the differentiation of a southern population (H. formosum subsp. formosum in the sense of C. L. Hitchcock) from a northern one [H. formosum subsp. scouleri (Hooker) C. L. Hitchcock] based on the broader, blunter, and less-glandular sepals in the latter, does not appear warranted.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
- Local floras:
BC, 
OR, 
WA - Local Web sites:
CalFlora, CalPhotos, 
Flora NW, 
Go Botany, 
IL Wildflowers, 
KS Wildflowers, 
MD Biodiversity, 
MI Flora, 
MN Wildflowers, 
MO Plants, 
PNW Herbaria, Turner Photog. 
WildflowerSearch
iNaturalist (observations)
USDA Plants Database- LBJ Wildflower Center
- SEINet
- Plants of the World Online
- Encyclopedia of Life
- Wikipedia
- Google Image Search
- Local floras: BC, CA, OR, WA
- Local Web sites: CalFlora, CalPhotos, Flora NW, PNW Herbaria,
SW CO Wildflowers - WildflowerSearch
- iNaturalist (observations)
- USDA Plants Database
- LBJ Wildflower Center
- SEINet
- Plants of the World Online
- Encyclopedia of Life
- Wikipedia
- Google Image Search
