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| 1 Bracts of the inflorescence foliaceous and overlapping; [alien species, cultivated and sometimes escaping in upland or bottomland situations]. |
| ..2 Bracts yellow or red; corolla white |
| ..2 Bracts green; corolla pink to purplish (rarely white) |
| 1 Bracts of the inflorescence small, neither foliaceous nor overlapping. |
| ....3 Corolla orange, 3.5-5 cm long; lower corolla lip unmarked |
| ....3 Corolla white, lavender, or purplish; lower corolla lip marked with darker stripes; [native species, of various wetlands]. |
| ......4 Inflorescence a panicle |
| ......4 Inflorescence a spike. |
| ........5 Spike densely flowered; seeds verrucose; primary leaves averaging 6-8× as long as wide; [of the Piedmont, Mountains, and Coastal Plain] |
| ........5 Spike loosely flowered; seeds smooth or minutely muricate (with very fine, sharp projections); primary leaves either ca. 2-6× as long as wide or > 8× as long as wide; [of the Coastal Plain]. |
| ..........6 Corolla purple, 18-30 mm long; leaves averaging > 8× as long as wide; cystoliths parallel to the midvein of the leaf; [of s. GA south into FL]. |
| ............ 7 Upper leaf blades 4-7 cm long, not channeled, tough but not fleshy; calyx segments 5-7 mm long, < 1 mm wide |
| ............ 7 Upper leaf blades 8-13.5 cm long, channeled, fleshy; calyx segments 11-15 mm long, ca. 1 mm wide |
| ..........6 Corolla pale lavender to white, 8-13 mm long; leaves averaging 2-6× as long as wide; cystoliths parallel to the secondary veins of the leaf; [of the Coastal Plain throughout our area]. |
| ............ ..8 Spikes lax, the flowers usually borne singly, secund; seeds smooth; leaves averaging ca. 5× as long as wide |
............ ..8 Spikes somewhat congested, the flowers borne in opposite pairs; seeds minutely muricate (with very fine, sharp projections); leaves averaging ca. 3× as long as wide |