Hypericum boreale
Hypericum
millepertuis bor é al, northern bog St. John's-wort, northern St. John's-wort
millepertuis, St. Andrew's cross, St. John's-wort
internodes 4-angled, apical internode shorter than adjacent one or almost absent.
internodes terete (not lined) or 2-, 4-, or 6-lined at first (lines usually raised), then sometimes becoming angled, terete, or winged;
bark smooth or striate, sometimes corky, punctiform.
spreading, sessile;
blade (concolor), broadly to narrowly oblong or elliptic to oblanceolate or round, 5–15 × 2–5 mm, papery to membranous, margins plane, apex rounded, basal veins 3–5, midrib branched or not.
cylindric to rounded-pyramidal, 1–13-flowered, branching mostly dichasial;
bracts not linear-subulate.
terminal, cymose, 2+-flowered, or flowers solitary, branching stellate [cupulate];
sepals persistent or deciduous, (3–)4–5, distinct or ± connate, margins sometimes glandular-ciliate;
petals persistent or deciduous, (3–)4–5[–6], contorted, yellow to orange, sometimes red-tinged;
stamens persistent or deciduous, (5–)10–300(–650), in continuous or interrupted ring or in (3–)4–5 fascicles, fascicles distinct or connate, each with 1–60+ stamens;
filaments distinct or basally connate;
anthers yellow to orange, oblong to ellipsoid, almost isodiametric, sometimes with amber or black gland on connective;
staminode fascicles 0 [3];
ovary 2–5-merous;
placentation axile to parietal;
ovules 2+ on each placenta;
styles distinct or ± connate basally, spreading to ± appressed.
3–5 mm diam.;
sepals usually lanceolate to narrowly oblong, rarely oblanceolate, equal, 2.5 × 0.8–1 mm, margins sometimes ciliate, not setulose-ciliate, apex rounded;
petals pale yellow, oblong, 1.7–3.5 mm;
stamens 5–16, scarcely grouped;
styles 0.5 mm;
stigmas broadly capitate.
narrowly ovoid to cylindric-ellipsoid, 4–5 × 2–2.5 mm, usually broadest at or near middle.
2–5-valved, sometimes with glandular vittae or vesicles.
0.4–0.7 mm;
testa finely linear-scalariform.
narrowly cylindric to ellipsoid, sometimes carinate;
testa foveolate or reticulate to scalariform [papillose].
= 12, 9–7, 6 (dihaploid).
= 16 [“18”].
Hypericum boreale
Hypericum
Where Hypericum boreale grows submerged, the plants are almost always sterile with elongated stems and suborbiculate leaves (H. boreale forma callitrichoides Fassett). Such plants intergrade shorewards with typical H. boreale (F. H. Utech and H. H. Iltis 1970). All other chromosome counts for H. mutilum and its near relatives have given n = 8; B. M. Kapoor’s (1972) count of 2n = 18 must be treated with reserve.
Hypericum mutile var. boreale (Britton) E. P. Bicknell is not a validly published name.
The discovery of Hypericum boreale near the mouth of Fraser River at Vancouver in 1989 extends the distribution of this species across Canada almost to the Pacific coast; this occurrence is almost certainly the result of recent introduction.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Species ca. 490 (54 in the flora).
Shrubs with deciduous leaves, petals, and stamens belong to either Hypericum sect. Ascyreia Choisy (with five stamen fascicles and five styles) or sect. Androsaemum (Duhamel) Godron (with five stamen fascicles and three or four styles). These are all introductions, mostly garden escapes. Those in sect. Ascyreia include: Hypericum calycinum Linnaeus, a low shrub with creeping stolons and flowers 50–95 mm diam. that has been found in California, Oregon, and Washington; H. ×moserianum Luquet ex André, its hybrid with H. patulum Thunberg, a low (sterile?) branching shrub with red anthers; and H. hookerianum Wight & Arnott, a shrub to 2 m tall with narrow leaves and a dense ring of relatively short stamens, recorded from California (its identity requires confirmation). In sect. Androsaemum, H. androsaemum is a deciduous shrub with relatively small flowers and baccate fruits that ripen from cherry-red to black; it has been found in British Columbia and in California and Washington.
Introduced herbaceous species with three stamen fascicles and three styles include: Hypericum hirsutum, with hairy stems and leaves (Ontario); H. tetrapterum, with four-winged internodes and lanceolate sepals (British Columbia and Washington); H. pulchrum with cordate leaves and red-tinged petals (Newfoundland, St. Pierre and Miquelon); and H. humifusum Linnaeus, a procumbent herb with unequal sepals (British Columbia).
(Discussion copyrighted by Flora of North America; reprinted with permission.)
1. Herbs, subshrubs, or shrubs, black glands absent; stamens in continuous or interrupted ring or in 4 or 5 barely discernable fascicles, each of 1 or 2 stamens | → 2 |
1. Herbs or shrubs, black and/or red glands usually present throughout, sometimes absent; stamens in 5 fascicles, each of 2+ stamens | → 3 |
2. Herbs (perennial), subshrubs, or shrubs; petals deciduous; stamens usually persistent, sometimes deciduous, 30–650, in continuous ring or in 4–5 barely discernable fascicles; styles ± appressed, bases distinct. | sect. Myriandra |
2. Herbs (annual or perennial); petals persistent; stamens persistent, (5–)10–80, usually in continuous or interrupted ring, sometimes in 5 barely discernable fascicles; styles ± spreading, bases distinct. | Hypericum informal sect. group Brathys |
3. Shrubs; leaves deciduous (base articulated); style bases distinct. | sect. Webbia |
3. Herbs (perennial); leaves persistent or tardily deciduous (base not articulated) or; style bases ± connate or distinct | → 4 |
4. Herbs, black glands absent; flowers 40–70 mm diam.; stamens 150, in 5 fascicles, fascicles usually distinct, rarely 1 pair connate; styles ± appressed, bases ± connate or distinct. | sect. Roscyna |
4. Herbs, black glands usually on leaves, sepals, and petals and, sometimes, on stems and anthers; flowers 6–35 mm diam.; stamens 20–109, in 5 fascicles, fascicles connate (as 2 + 2 + 1); styles spreading, bases distinct. | Hypericum informal sect. group Hypericum |
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WA
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