Click the number at the start of a key lead to highlight both that lead and its corresponding lead. Click again to show only the two highlighted leads. Click a third time to return to the full key with the selected leads still highlighted.
1 Flowers primarily terminal, sometimes lateral, in dense globose or ovoid spikes, flowers sessile, corolla 15-20 (-25) mm diameter; [cultivated and rarely escaped]
....3 Corollas 3.5-5 mm wide, sepals glabrous or sparsely pilose, ciliate, 2-2.5 mm; leaf blades linear to narrowly lanceolate; stems sparsely pubescent; [historically as a waif on ballast in MD]
......4 Stems pubescent (rarely glabrous), corolla 4.5-7 mm, erect to prostrate.
......4 Stems glabrous to sparingly pubescent, corolla 8-12 mm, stems usually prostrate to ascending
........5 Sepals lanceolate to narrow-lanceolate, 4-5 mm, with spreading hairs; phyllotaxis pentastichous; leaves with pinnate venation; [calcareous glades and barrens of c. TN, and west of the Mississippi River in MS, AR, and TX westwards]
..........6 Leaves ovate, < 2× as long as wide, stems strictly prostrate [pine rocklands, Big Pine Key, FL]
............ 7 Leaves glabrous above and below; stems wiry-filiform, often erect and many-branched from base; leaves linear to linear-subulate; [rocklands of s. FL]
............ ..8 Leaves pubescent above; [rocklands of s. FL]
............ ..8 Leaves glabrous above; [widespread in the Coastal Plain]