Triadenum fraseri
Triadenum tubulosum
bog St. John's wort, Fraser's marsh-St. John's-wort, Fraser's St. John's-wort, marsh St. John's-wort, millepertuis de Fraser
lesser marsh St. Johnswort
shallowly 4-lined at first, then terete.
internodes 2-lined at first, then terete.
sessile, sometimes amplexicaul;
blade broadly ovate or triangular-ovate to oblong, 15–50(–70) × 10–40(–50) mm, base usually ± shallowly cordate, rarely truncate, apex rounded to retuse, gland dots laminar (relatively dense) and intramarginal.
sessile or (distal) subsessile, rarely amplexicaul;
blade narrowly oblong or elliptic to oblanceolate, 50–120(–150) × 10–40(–50) mm, base rounded to truncate or subcordate, apex rounded or rounded-apiculate to retuse, gland dots intramarginal.
spiciform-cylindric, 3–7-flowered from terminal node, with sessile or pedunculate inflorescences and flowering branches from to 4 proximal nodes.
15 mm diam.;
sepals narrowly oblong, 4–7 × 1–1.5 mm, apex acute to obtuse;
petals elliptic-obovate, 5–8 mm;
stamen fascicles 4–7 mm;
filaments 1/2+ connate;
styles 0.8–1.5 mm.
cylindric, 8–12 × 3.5–4 mm, apex obtuse.
0.8–1.2 mm.
Triadenum fraseri
Triadenum tubulosum
According to B. Boivin (1967), Triadenum fraseri (as Hypericum virginicum) was introduced into British Columbia from eastern Canada in peat. It seems to be almost always distinguishable from T. virginicum and to have a distinct habitat; it merits specific rank.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
The absence of laminar glands in leaves is a more reliable characteristic for differentiating Triadenum tubulosum from T. walteri than sessile versus petiolate leaves, which are not always quite sessile towards the inflorescence in T. tubulosum, or sepals, which can be obtuse in both.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
- Local floras:
BC, 
WA - Local Web sites:
Flora NW, 
Go Botany, 
IL Wildflowers, 
MD Biodiversity, 
MI Flora, 
MN Wildflowers, 
PNW Herbaria 
WildflowerSearch
iNaturalist (observations)
USDA Plants Database- LBJ Wildflower Center
- SEINet
- Plants of the World Online
- Encyclopedia of Life
- Wikipedia
- Google Image Search
LA Plants
MO Plants
