Bull. Torrey Bot. Club 25: 616. 1898.
Shrubs, erect, branches ascending, 4–7 dm. Stems: internodes narrowly 4-winged at first, then 2-lined. Leaf blades oblong to elliptic-oblong, 20–40 × 12–20 mm, base not articulated, broadly cuneate, margins usually plane, rarely recurved, apex rounded to retuse, midrib with 6 pairs of branches. Inflorescences terminal (1–)3–5(–8)-flowered, narrowly branched. Flowers 15 mm diam.; sepals tardily deciduous, not enclosing capsule, 5, spatulate to elliptic or ovate, unequal, 3–5 × 1.5–2.3 mm; petals 5, coppery yellow, oblong, 8–10 mm length 2 times sepals; stamens deciduous, 60–80; ovary 3-merous, placentation incompletely axile. Capsules cylindric-conic, 6–15 × 4.5–8 mm. Seeds scarcely carinate, 1.8–2 mm; testa finely scalariform-reticulate.
Phenology: Flowering summer (Jun).
Habitat: Stream banks and moist woods, coastal plain and inland valleys
Elevation: 10–500 m
Ark., Fla., La., Okla., Tex.
Hypericum apocynifolium has been included in H. nudiflorum; it can be distinguished from the latter by the fewer, larger flowers with relatively longer, persistent sepals, the larger, thicker-walled capsules, and the seeds, which are ridged and straight rather than carinate and curved.
A record from Georgia in the Flint River drainage has not been verified.