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mountain St. John's wort

bushy St. John's-wort, dense St. Johnswort

Habit Shrubs, decumbent, spreading and rooting, wiry, branches ascending to erect, forming compact mats, 0.5–4.5 dm. Shrubs, erect, forming slender bush, 6–30 dm.
Stems

internodes 4-lined.

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

Leaf

blades oblong or elliptic to obovate, 4–25 × 2–12 mm, base not articulated, cuneate, margins plane, apex rounded, midrib with 2–4 pairs of branches.

blades narrowly elliptic-oblong or oblanceolate to linear, 20–45 × 2–7 mm, base articulated, narrowly cuneate to attenuate, margins recurved to revolute, apex apiculate-rounded to subacute, midrib with 14–17 pairs of branches.

Inflorescences

1(–5)-flowered.

broadly pyramidal to broadly cylindric, 5–25-flowered from apical node, with (2–)5–15-flowered dichasia from 1–2 proximal nodes.

Flowers

20–25 mm diam.;

sepals persistent, not enclosing capsule, 5, broadly elliptic to elliptic-spatulate or obovate, subequal, 4–5 × 2.5–3 mm;

petals 5, golden yellow, oblanceolate, 6–10.5 mm;

stamens persistent, 100;

ovary 3-merous.

10–17(–20) mm diam.;

sepals deciduous, not enclosing capsule, 5, narrowly oblong to oblanceolate-spatulate, unequal or subequal, 4–6 × 1–1.5 mm, basal veins 1–3;

petals 5, deep golden yellow, obovate-oblanceolate, 6–9 mm;

stamens deciduous, 100–150;

ovary 3–4(–5)-merous.

Capsules

ovoid to ovoid-cylindric, 8–12 × 5 mm.

narrowly ovoid conic to cylindric-ovoid, 5–6(–7) × 2–3 mm, not or scarcely lobed.

Seeds

narrowly to broadly carinate, 1.5–2 mm;

testa finely foveolate-reticulate.

not carinate, 0.8–1.3 mm;

testa linear-reticulate.

2n

= 18.

Hypericum buckleyi

Hypericum densiflorum

Phenology Flowering early–mid summer (Jun–Jul). Flowering summer (Jun–Aug).
Habitat Seepage areas, moist rock crevices, ditches, road embankments Wet or moist habitats (meadows, lake margins, pinelands, etc.), road embankments, rocky hillsides
Elevation 900–1600 m (3000–5200 ft) 0–1000 m (0–3300 ft)
Distribution
from FNA
GA; NC; SC
[BONAP county map]
from FNA
AL; DE; GA; KY; MD; NC; NJ; PA; SC; TN; VA; WV
[WildflowerSearch map]
[BONAP county map]
Discussion

Hypericum buckleyi is found throughout the southern Appalachian Mountains.

The decumbent habit and persistent sepals and stamens distinguish Hypericum buckleyi from its nearest relative, H. prolificum.

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

Hybrid intermediates between Hypericum densiflorum and H. lobocarpum occur in northwestern Alabama, and a narrow-leaved, small-flowered form in Tennessee and northern Georgia (H. interior) verges toward H. galioides. Hypericum densiflorum is always distinct from H. prolificum in the wild; these species hybridize in gardens. Hypericum ×arnoldianum Rehder, known in cultivation only, was thought by Rehder to have the parentage H. galioides × lobocarpum; on both morphological and cytological grounds, the conclusion of W. P. Adams (1972) that it was H. densiflorum × lobocarpum seems much more likely.

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

Source FNA vol. 6, p. 81. FNA vol. 6, p. 78.
Parent taxa Hypericaceae > Hypericum > sect. Myriandra Hypericaceae > Hypericum > sect. Myriandra
Sibling taxa
H. adpressum, H. anagalloides, H. apocynifolium, H. ascyron, H. boreale, H. brachyphyllum, 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. prolificum, 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. crux-andreae, H. cumulicola, 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 H. glomeratum, H. interior, H. nothum, H. prolificum var. densiflorum
Name authority M. A. Curtis: Amer. J. Sci. Arts 44: 80. (1843) Pursh: Fl. Amer. Sept. 2: 376. (1813)
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