About Hypericum tetrapetalum Lam.
Fourpetal St. Johnswort (scientific name Hypericum tetrapetalum Lam.) is a perennial herb or small shrub with a woody base, reaching a height of 20 to 100 cm (7.9 to 39.4 inches). Young stems are two- or four-lined, and develop into two-lined or terete stems as they age. Its leaves range in shape from oblong to triangular-ovate, measuring 5–35 mm (0.20–1.38 in) long and 4–15 mm (0.16–0.59 in) wide, with heart-shaped, clasping bases. Terminal flowerheads bear one to three flowers; each flower is 20–30 mm (0.79–1.18 in) in diameter, with 4 bright yellow petals and around 100 stamens. This species produces flowers through most of the year, and its seed capsules are three-parted. Fourpetal St. Johnswort differs from its close relative Hypericum crux-andreae by its broader leaves with clasping bases. The distributions of these two species overlap in southern Georgia and northern Florida, but no apparent hybrids between them have been observed. In the United States, Hypericum tetrapetalum is distributed across Alabama, Georgia, and Florida. It also grows in western Cuba. This species inhabits wet pinelands and ditches with sandy soil.