The green links below add additional plants to the comparison table. Blue links lead to other Web sites.
enable glossary links

myrtleleaf St. Johnswort

sandhill St. Johnswort

Habit Shrubs, erect, with woody caudex, unbranched or branched distally, 3–10 dm, bark on older stems corky. Shrubs, decumbent, straggling and rooting, forming low, rounded clumps or mats, 1–5 dm.
Stems

internodes 4-lined.

internodes (4-) or 6-lined at first, then terete.

Leaf

blades oblong-ovate to triangular-lanceolate, 8–40 × (5–)7–20 mm, base articulated, subcordate-amplexicaul, margins recurved, apex rounded, midrib with 3 or 4 pairs of branches.

blades linear-subulate, 13–25 × 0.5–0.8 mm, base articulated, parallel, margins revolute, apex rounded to retuse, midrib unbranched.

Inflorescences

hemispheric to ± flat-topped, 7–30-flowered, widely branched, with flowers or flowering branches from to 3 proximal nodes.

narrowly pyramidal, 1–3-flowered, with 1–3(–5)-flowered dichasia from to 5 proximal nodes, without additional flowering branches;

pedicels 0.5 mm.

Flowers

15–25 mm diam.;

sepals persistent, not enclosing capsule, 5, ovate to lanceolate, unequal to subequal, 5–8 × 2–4.5 mm;

petals 5, bright yellow, obovate to oblong-lanceolate, 8–15 mm;

stamens deciduous, 200;

ovary 3(–4)-merous.

12–14 mm diam.;

sepals deciduous, not enclosing capsule, 5, linear-subulate, unequal, (3–)4.5–7 × 0.5–0.8 mm;

petals 5, golden yellow, oblanceolate-oblong, 5–7.5 mm;

stamens deciduous, 100;

ovary 3-merous.

Capsules

pyramidal-ovoid, 5–6 × 3–4 mm.

ovoid, 3–4 × 2–2.5 mm.

Seeds

narrowly carinate, 1 mm;

testa shallowly linear-reticulate.

carinate, 0.7 mm;

testa not seen.

2n

= 18.

Hypericum myrtifolium

Hypericum lloydii

Phenology Flowering late spring–summer (May–Jul), sometimes fall. Flowering summer (Aug).
Habitat Moist pinewoods, grassy bogs, pond margins, ditches Dry habitats (pine woods, granite outcrops, roadside embankments), inner coastal plain and foothills
Elevation 0–200 m (0–700 ft) 100–300 m (300–1000 ft)
Distribution
from FNA
AL; FL; GA; MS; SC
[WildflowerSearch map]
[BONAP county map]
from FNA
AL; GA; NC; SC
[WildflowerSearch map]
[BONAP county map]
Discussion

Hypericum myrtifolium is related to H. frondosum; it differs in its shorter, usually amplexicaul leaves, the widely dichasially branched inflorescences, and persistent sepals.

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

The habit, leaf shape, and drier habitats distinguish Hypericum lloydii from H. galioides.

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

Source FNA vol. 6, p. 84. FNA vol. 6, p. 79.
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. 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. 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. 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. 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 Brathydium myrtifolium, H. glaucum, H. sessiliflorum, Myriandra glauca H. galioides var. lloydii
Name authority Lamarck: in J. Lamarck et al., Encycl. 4: 180. (1797) (Svenson) W. P. Adams: Contr. Gray Herb. 189: 32. (1962)
Web links