| Hypericum tenuifolium | |
|---|---|
 | |
Scientific classification | |
| Kingdom: | Plantae |
| Clade: | Tracheophytes |
| Clade: | Angiosperms |
| Clade: | Eudicots |
| Clade: | Rosids |
| Order: | Malpighiales |
| Family: | Hypericaceae |
| Genus: | Hypericum |
| Section: | H.sect. Myriandra |
| Subsection: | H.subsect. Centrosperma |
| Species: | H. tenuifolium |
| Binomial name | |
| Hypericum tenuifolium | |
| Synonyms[3] | |
| |
Hypericum tenuifolium, known asAtlantic St. John's-wort[4] andsandhill St. John's-wort,[5] is a species offlowering plant in the St. John's wort family,Hypericaceae. It isendemic[1] to theSoutheastern United States.[6]
Atlantic St. John's-wort is a small, spreading shrub, growing 10–50 cm (4–20 in) tall and forming mats.[6][7] The leaves are very narrow, hence its nametenuifolium (from Latin tenuis 'thin' and folium 'leaf'), and are only 0.4–0.8 mm (0.016–0.031 in) broad and 4–11 mm (1⁄8–3⁄8 in) long, with rounded tips andrevolute margins. The flowerheads are narrowly cylindric, producing 1–7 flowers. Each flower is10–14 mm (3⁄8–1⁄2 in) broad with 5 sepals, 5 bright yellow petals, and 50–90 stamens. The ovaries are three-parted, forming cylindric capsule fruits. It flowers in the summer, typically June through September, but sometimes as late as December.[5]
Hypericum tenuifolium occurs in theAtlantic coastal plain in the southeasternUnited States, inAlabama,Florida,Georgia,North Carolina, andSouth Carolina.[6] Its habitat includes dry, open,sandy areas such as pineflatwoods, pinesavannas, andsandhills.[6][5]
