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shrubby St. John's-wort

Atlantic St. Peter's-wort, St. Peter's wort

Habit Shrubs, erect or ± diffuse, forming rounded or irregular bush, (2–)7.5–15(–20) dm. Shrubs, usually erect to suberect, rarely decumbent and rooting, usually unbranched, rarely sparsely branched distally, 1–13.5 dm.
Stems

internodes 4-lined at first, then 2-lined to terete.

internodes 2–4-lined at first, then 2-winged.

Leaf

blades narrowly oblong to narrowly elliptic-oblanceolate, 30–70 × 6–15 mm, base articulated, attenuate to narrowly cuneate, margins plane to recurved, apex rounded-apiculate to acute, midrib with 10–16 pairs of branches.

blades usually oblong to elliptic, rarely obovate to oblanceolate or triangular-ovate, 12–36 × 6–16 mm, base articulated, rounded to slightly cordate-amplexicaul, without glandlike auricles, margins plane to subrecurved, apex rounded to obtuse, midrib with to 3 pairs of branches.

Inflorescences

cylindric, (1–)3–7(–9)-flowered from apical node, with paired single flowers or triads or 1–3(–7)-flowered branches from 2+ proximal nodes.

± narrowly cylindric to narrowly pyramidal, 1–3(–7)-flowered, branching dichasial, from to 4 proximal nodes.

Flowers

15–30 mm diam.;

sepals deciduous, not enclosing capsule, 5, elliptic to obovate or oblanceolate-spatulate, unequal or subequal, 4–8 × 1.5–4 mm;

petals 5, golden yellow, obovate to oblanceolate-spatulate, 7–15 mm;

stamens deciduous, 150–500;

ovary 3(–5)-merous, placentation incompletely axile.

20–30 mm diam.;

sepals persistent, enclosing capsule, 4, unequal, outer broadly ovate to circular, 9–20 × 9–18 mm, apex apiculate or obtuse to rounded, inner narrowly elliptic to lanceolate, 7–14 × 2–4 mm, apex acute to subacute;

petals 4, bright yellow, obovate, 11–18 mm;

stamens persistent, 80–100;

ovary 3(–4)-merous.

Capsules

usually narrowly ovoid-conic to ovoid, rarely ellipsoid, 7–13 × 4–7 mm.

narrowly ellipsoid-ovoid, 7–10 × 5–6.5 mm.

Seeds

carinate, 1.5–2 mm;

testa linear-reticulate.

not carinate, 0.8 mm;

testa shallowly scalariform.

2n

= 18.

= 18.

Hypericum prolificum

Hypericum crux-andreae

Phenology Flowering summer (Jun–Sep). Flowering summer–fall.
Habitat Rocky slopes, embankments, dry stream bottoms, woodland (in north), on limestone or granite Moist to dry, pine savannas and flatwoods, meadows, bogs, other wet habitats, lake and pond margins
Elevation 50–600+ m (200–2000+ ft) 0–1500 m (0–4900 ft)
Distribution
from FNA
AL; AR; DC; DE; FL; GA; IA; IL; IN; KY; LA; MD; MI; MO; MS; NC; NJ; NY; OH; OK; PA; SC; TN; TX; VA; WI; WV; ON
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from FNA
AL; AR; DC; DE; FL; GA; KY; LA; MD; MS; NC; NJ; NY; OK; PA; SC; TN; TX; VA
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[BONAP county map]
Discussion

Hypericum prolificum is variable, the most luxuriant form being found in the southwestern part of its range. Natural hybrids have not been recorded; it hybridizes in gardens with H. densiflorum (H. x\arnoldianum Rehder), H. frondosum, H. kalmianum, and H. lobocarpum (H. x\dawsonianum Rehder).

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Hypericum crux-andreae, long known as Ascyrum stans, is a derivative of H. frondosum in which the tetramerous tendency in the perianth has become fixed. The low, multistemmed form with cuneate leaves, longer-

pedicellate flowers, and shorter sepals (A. cuneifolium, A. stans var. obovatum) cannot be separated from typical H. crux-andreae.

Linnaeus included “Hypericum ex terra mariana, floribus exiguis luteis” under his phrase name for Ascyrum crux-andreae; that element of the protologue refers to H. mutilum Linnaeus; see N. K. B. Robson (1980).

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Source FNA vol. 6, p. 76. FNA vol. 6, p. 85.
Parent taxa Hypericaceae > Hypericum > sect. Myriandra Hypericaceae > Hypericum
Sibling taxa
H. adpressum, H. anagalloides, H. apocynifolium, H. ascyron, H. boreale, H. brachyphyllum, H. buckleyi, H. canadense, H. canariense, H. chapmanii, H. cistifolium, H. concinnum, H. crux-andreae, H. cumulicola, H. densiflorum, H. denticulatum, H. dolabriforme, H. drummondii, H. edisonianum, H. ellipticum, H. erythreae, H. fasciculatum, H. frondosum, H. galioides, H. gentianoides, H. graveolens, H. gymnanthum, H. harperi, H. hypericoides, H. kalmianum, H. lissophloeus, H. lloydii, H. lobocarpum, H. maculatum, H. majus, H. microsepalum, H. mutilum, H. myrtifolium, H. nitidum, H. nudiflorum, H. paucifolium, H. perforatum, H. pseudomaculatum, H. punctatum, H. radfordiorum, H. scouleri, H. setosum, H. sphaerocarpum, H. suffruticosum, H. tenuifolium, H. tetrapetalum, H. virgatum, H. ×mitchellianum
H. adpressum, H. anagalloides, H. apocynifolium, H. ascyron, H. boreale, H. brachyphyllum, H. buckleyi, H. canadense, H. canariense, H. chapmanii, H. cistifolium, H. concinnum, H. cumulicola, H. densiflorum, H. denticulatum, H. dolabriforme, H. drummondii, H. edisonianum, H. ellipticum, H. erythreae, H. fasciculatum, H. frondosum, H. galioides, H. gentianoides, H. graveolens, H. gymnanthum, H. harperi, H. hypericoides, H. kalmianum, H. lissophloeus, H. lloydii, H. lobocarpum, H. maculatum, H. majus, H. microsepalum, H. mutilum, H. myrtifolium, H. nitidum, H. nudiflorum, H. paucifolium, H. perforatum, H. prolificum, H. pseudomaculatum, H. punctatum, H. radfordiorum, H. scouleri, H. setosum, H. sphaerocarpum, H. suffruticosum, H. tenuifolium, H. tetrapetalum, H. virgatum, H. ×mitchellianum
Synonyms Brathys prolifica, H. spathulatum, Myriandra ledifolia, M. prolifica, M. prolifica var. spathulata, M. spathulata Ascyrum crux-andreae, A. cuneifolium, A. grandiflorum, A. simplex, A. stans var. obovatum, Hypericoides crux-andreae, H. stans
Name authority Linnaeus: Mant. Pl. 1: 106. (1767) (Linnaeus) Crantz: Inst. Rei Herb. 2: 520. (1766)
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