Rhynchospora grayi Kunth

Of all North American species of Rhynchospora, R. grayi appears best adapted to the xeric conditions found in the coarser sands of the longleaf pine-scrub oak–dominated yellow sandhills. Interestingly, it seems seldom to mix with its closest relative, R. megalocarpa, which is more often found in white sandhills.

Plants perennial, cespitose, 10–100 cm; rhizomes absent. Culms erect or excurved, leafy, obscurely trigonous, slender, firm. Leaves shorter than culms; blades spreading to ascending, linear, proximally flat, 2–4 mm wide, apex involute, then trigonous, subulate. Inflorescences: spikelet clusters 1–4, loose to dense, broadly turbinate, lobed or hemispheric; peduncles and branches ascending; leafy bracts exceeding proximal, sometimes distal, clusters. Spikelets light red brown, ellipsoid or narrowly ovoid, 4–5 mm, apex acute to acuminate; fertile scales broadly ovate, 3.5–4.5 mm, apex acute or acuminate, apiculate. Flowers: perianth bristles mostly 6, reaching from fruit midbody to tubercle tip or beyond, antrorsely barbellate. Fruits 1(–2) per spikelet, 2.5–3 mm; body dark brown, broadly, tumidly obovoid, 2–2.5 × 2–2.5 mm, apically buttressed to tubercle; surfaces finely transversely rugulose or nearly level, with fine transverse rows of pits or low papillae, often appearing nearly smooth; tubercle low conic, 0.4–0.6 mm, apiculate.

Ala., Fla., Ga., La., Miss., N.C., S.C., Tex., Va.; West Indies.

Fruiting spring–summer.

Sandy pinelands and sandhills, particularly in longleaf pine type; 0–300m.

Phaeocephalum grayi (Kunth) House; Rhynchospora distans Elliott 1816, not (Michaux) Vahl 1805; R. elliottii A. Gray 1835, not A. Dietrich 1833; Schoenus distans Muhlenberg; S. fuscus Muhlenberg

Rhynchospora grayi là loài thực vật có hoa trong họ Cói. Loài này được Kunth miêu tả khoa học đầu tiên năm 1837.