About Hypericum setosum L.
Hypericum setosum L. is an erect, pubescent annual or biennial herb that grows 20–75 cm tall and produces few branches. Its leaves are simple, opposite, entire, ascending, sessile, and clasping at the base, ranging from elliptic-lanceolate to ovate in shape. Leaves measure 3–15 mm long and 2–8 mm wide, are typically 1-nerved, and have an acute tip. Flowers grow on alternate or terminal ascending branches arranged in a cymose inflorescence. Each flower is perfect, regular, bracteate, and has either short pedicels or is subsessile. It bears five ciliate sepals 3–4.5 mm long, and five petals 4–7 mm long; petals are usually yellow or pink, and often marcescent. Numerous stamens are arranged in basal clusters. The ovary is superior and unilocular, with three or four separate styles that are 1.5–2.5 mm long, each topped with a capitate stigma. The fruit is an ovoid capsule 4–5 mm long and 2.5–3.5 mm wide that dehisces longitudinally. Numerous seeds are produced, each yellow, lustrous, around 0.5 mm long, and with an areolate surface.
This species is distributed from Southeast Virginia south to central peninsular Florida, and west to Southeast Texas. It grows in pine savannas, wet pine flatwoods, boggy areas, fireplow lines, and scrapes. It is classified as a facultative wetland species, and is occasionally found in non-wetland habitats. Ecologically, Hypericum setosum forms a persistent soil seed bank that can remain viable for several years.
