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| 1 Leaf sheath fronts yellow, thickened, and not fragile at the top; leaf blades papillose adaxially (at 25× magnification) |
| 1 Leaf sheath fronts green or whitish, thin, and fragile at the top; leaf blades not papillose adaxially. |
| ..2 Leaf sheath fronts smooth. |
| ....3 Larger perigynia 6-8 mm long; leaves to 12 mm wide |
| ....3 Larger perigynia 3-5 mm long; leaves to 7 mm wide. |
| ......4 Perigynia smoothly rounded at base, not distended; perigynium veins 3-5 abaxially, 0 adaxially |
| ......4 Perigynia cordate at base, distended; perigynium veins 10-12 abaxially, 7 adaxially |
| ..2 Leaf sheath fronts rugose. |
| ........5 Perigynia broadly rounded at base, not distended; perigynium veins 3-5 abaxially, 0 adaxially |
| ........5 Perigynia cordate or truncate at base, distended; perigynium veins 15 abaxially, 7 adaxially. |
| ..........6 Perigynia (5-) avg. 5.4 (-6) mm long, the beak > 3 mm long; larger leaves mostly 8-17 mm wide; perigynium scales cuspidate to short-awned; [mostly of the Coastal Plain and lower Piedmont] |
| ..........6 Perigynia (4-) avg. 4.7 (-5) mm long, the beak < 2.5 mm long; larger leaves mostly 4-10 mm wide; perigynium scales acuminate to cuspidate; [widespread in our area] |