Anglestem Beaksedge

Rhynchospora caduca has its closest relationships with the even more robust R. odorata Grisebach, on the one hand, and the swamp inhabiting, more slender, and rhizomatous R. mixta Britton ex Small, on the other. Intergrades with R. odorata appear in Alabama and northwest Florida; intergrades with R. mixta appear where ranges overlap in both the Atlantic and Gulf coastal plains.

Plants perennial, cespitose, 70–150 cm; rhizomes often present, short, scaly. Culms erect or ascending, leafy, trigonous. Leaves exceeded by culm; blades linear, proximally 4–7 mm wide, apex trigonous, tapering. Inflorescences terminal and axillary; clusters 3–6, mostly dense, narrowly to broadly turbinate, branches ascending; leafy bracts exceeeding proximalmost inflorescences. Spikelets rich brown, ovoid, (3–)4–5 mm, apex acuminate; fertile scales ovate, 2.5–3.5 mm, apex acuminate, midrib included or short excurrent. Flowers: perianth bristles mostly 6, exceeding tubercle tip. Fruits mostly 3–4 per spikelet, 2–2.2 mm; body brown on short pedicellar (to 0.3 mm) stalk, broadly obovoid, lenticular, 1.3–1.5 × 1–1.5 mm, surfaces transversely rugulose, vertically finely striate and rectangular alveolate; tubercle compressed, triangular acuminate, 0.5–0.8 mm, edges setulose.

Ala., Ark., Fla., Ga., La., Miss., N.C., Okla., S.C., Tenn., Tex., Va.

Fruiting summer–fall.

Low meadows, clearings, marshes, marsh borders, seeps, bog moats, savannas, ditches, pine flatwoods, swamps; 0–400m.

Phaeocephalum caducum (Elliott) House; Rhynchospora patula A. Gray

Rhynchospora caduca, commonly called anglestem beaksedge, is a species of flowering plant in the sedge family (Cyperaceae). It is native to North America, where it is found in the southeastern United States. Its typical natural habitat is in low, wet areas, such as in marshes, seeps, tidal swamps, pine savannas, and flatwoods.

Rhynchospora caduca is a cespitose perennial, usually with short scaly rhizomes. It is tall for a Rhynchospora, growing up to 150 cm high. It produces fruits in summer through fall. It is closely related to Rhynchospora mixta and Rhynchospora odorata, and local introgressant populations have been noted.