Flora of the Southeastern United States

Leaf sheath fronts green or whitish, thin, and fragile at the top; leaf blades not papillose adaxially.

Leaf sheath fronts smooth.

Larger perigynia 6-8 mm long; leaves to 12 mm wide

Larger perigynia 3-5 mm long; leaves to 7 mm wide.

Perigynia smoothly rounded at base, not distended; perigynium veins 3-5 abaxially, 0 adaxially

Perigynia cordate at base, distended; perigynium veins 10-12 abaxially, 7 adaxially

Leaf sheath fronts rugose.

Perigynia broadly rounded at base, not distended; perigynium veins 3-5 abaxially, 0 adaxially

Perigynia cordate or truncate at base, distended; perigynium veins 15 abaxially, 7 adaxially.

Perigynia (5-) avg. 5.4 (-6) mm long, the beak > 3 mm long; larger leaves mostly 8-17 mm wide, the blades glaucous; perigynium scales cuspidate to short-awned; [mostly of the Coastal Plain and lower Piedmont]

Perigynia (4-) avg. 4.7 (-5) mm long, the beak < 2.5 mm long; larger leaves mostly 4-10 mm wide, the blades green; perigynium scales acuminate to cuspidate; [widespread in our area]

Beak of the perigynium shorter than the body.

Perigynia somewhat abruptly contracted into a beak ca. 0.5 × as long as the perigynium body; ventral surface of the perigynium with several incomplete veins basally; culms sharply triangular and narrowly winged, somewhat spongy and easily crushed; dorsal leaf sheaths green; ventral leaf sheaths with scattered red dots, and transversely rugose; [normally of shaded locations]

Perigynia tapering into a beak, much shorter than the perigynium body; ventral surface of the perigynium with several inconspicuous complete veins; culms inconspicuously triangular to roundish, not winged, neither spongy nor easily crushed; dorsal leaf sheaths dark blue-green with conspicuous white dots; ventral leaf sheaths without scattered red dots, not transversely rugose; [normally of sunny locations]

Beak of the perigynium as long as, or longer than, the body.

Ventral leaf sheath margins with orange-red dots; achene ovate-lanceolate; perigynium wall adhering to achene

Ventral leaf sheath margins without orange-red dots; achene broadly ovate to ovate-orbicular; perigynium wall not adhering to the achene (or only slightly so).

Ventral leaf sheaths transversely rugose, more or less convex at the apex and prolonged upward past the base of the blade, friable.

Perigynia (5-) avg. 5.4 (-6) mm long, the beak > 3 mm long; inflorescences to 15 cm long; larger leaves mostly 8-17 mm wide, the blades glaucous; perigynium scales cuspidate to short-awned; [mostly of the Coastal Plain and lower Piedmont]

Perigynia (4-) avg. 4.7 (-5) mm long, the beak < 2.5 mm long; inflorescences to 10 cm long; larger leaves mostly 4-10 mm wide, the blades green; perigynium scales acuminate to cuspidate; [widespread in our area]