Hypericum scouleri

Hooker

Fl. Bor.-Amer. 1: 111. 1831.

Common names: Scouler’s St. John’s wort
Synonyms: Hypericum formosum subsp. scouleri (Hooker) C. L. Hitchcock H. formosum var. scouleri (Hooker) J. M. Coulter H. nortoniae H. scouleri subsp. nortoniae (M. E. Jones) J. M. Gillett
Treatment appears in FNA Volume 6. Treatment on page 100. Mentioned on page 98.

Herbs erect or ascending, with rooting, creeping, branching base, 0.5–6.6 (–8) dm. Stems: internodes usually weakly 2-lined, sometimes not lined, without black glands, rarely with reddish glands. Leaves usually spreading, rarely erect, sessile or (proximal) subpetiolate; blade oblongelliptic 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). Inflorescences cylindric to narrowly pyramidal, (1–) 8–20-flowered. Flowers 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. Capsules oblanceoloid, 6–10 × 3.5–6 mm, with longitudinal vittae. Seeds not carinate, (0.5–) 0.7–0.8 mm; testa linear-reticulate. 2n = 16.


Phenology: Flowering summer (Jun–Sep).
Habitat: Wet meadows and banks, coniferous forests, screes, lake margins, marshes, tidal shores
Elevation: 0–2900 m

Distribution

V6 176-distribution-map.jpg

Alta., B.C., Ariz., Calif., Colo., Idaho, Mont., Nev., N.Mex., Oreg., Utah, Wash., Wyo., Mexico (Baja California), Mexico (Baja California Sur), Mexico (Chihuahua), Mexico (Coahuila), Mexico (Durango), Mexico (Sonora), Mexico (Zacatecas)

Discussion

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.

Selected References

None.

Lower Taxa

None.

"dm" is not declared as a valid unit of measurement for this property.

... more about "Hypericum scouleri"
reddish +  and black +
gland black +
oblong;ellipsoid +
acute;rounded +
Norman K. B. Robson +
Hooker +
striate +  and smooth +
punctiform +
branching +  and rooting +
distinct +
subcordate +  and rounded or cuneate +
2.8 cm28 mm <br />0.028 m <br /> (3.2 cm32 mm <br />0.032 m <br />) +
1.5 cm15 mm <br />0.015 m <br /> (1.8 cm18 mm <br />0.018 m <br />) +
1.2 cm12 mm <br />0.012 m <br /> (2.8 cm28 mm <br />0.028 m <br />) +
elliptic +  and triangular-ovate or obovate +
0.6 cm6 mm <br />0.006 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
0.6 cm6 mm <br />0.006 m <br /> (1 cm10 mm <br />0.01 m <br />) +
oblanceoloid +
0.35 cm3.5 mm <br />0.0035 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
Scouler’s St. John’s wort +
Alta. +, B.C. +, Ariz. +, Calif. +, Colo. +, Idaho +, Mont. +, Nev. +, N.Mex. +, Oreg. +, Utah +, Wash. +, Wyo. +, Mexico (Baja California) +, Mexico (Baja California Sur) +, Mexico (Chihuahua) +, Mexico (Coahuila) +, Mexico (Durango) +, Mexico (Sonora) +  and Mexico (Zacatecas) +
0–2900 m +
connate +  and distinct +
0.6 cm6 mm <br />0.006 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
black +  and reddish +
laminar +  and intramarginal +
Wet meadows and banks, coniferous forests, screes, lake margins, marshes, tidal shores +
(1-)8-20-flowered +
axillary +  and terminal +
cylindric +  and narrowly pyramidal +
lined +  and 2-lined +
terete +  and angled +
subpetiolate +  and sessile +
deciduous +  and persistent +
erect;spreading +
glandular-ciliate +
3(-4)-merous +
axile +  and parietal +
glanduliferous +
contorted +  and imbricate +
red-tinged +  and golden yellow +
persistent +
distinct +
oblanceolate +
0.7 cm7 mm <br />0.007 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
Flowering summer (Jun–Sep). +
Fl. Bor.-Amer. +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.07 cm0.7 mm <br />7.0e-4 m <br />) +
not carinate +
0.07 cm0.7 mm <br />7.0e-4 m <br /> (?) +  and 0.08 cm0.8 mm <br />8.0e-4 m <br /> (?) +
persistent +
connate +  and distinct +
ovate;lanceolate or narrowly oblong +
unequal +  and subequal +
0.1 cm1 mm <br />0.001 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
persistent +
connate +  and distinct +
elongate +
0.2 cm2 mm <br />0.002 m <br /> (?) +  and 0.8 cm8 mm <br />0.008 m <br /> (?) +
Hypericum formosum subsp. scouleri +, H. formosum var. scouleri +, H. nortoniae +  and H. scouleri subsp. nortoniae +
Hypericum scouleri +
Hypericum sect. Hypericum +
species +
scalariform +
reticulate +  and foveolate +
south +, west +  and north +
ascending +  and erect +
hairy +  and glabrous +
6 +, 9 +  and 7 +