Flora of North America species comparison

usually 1 per caudex branch, arising from center of rosette, elevated on woody base or from ground surface, (2–)3–8 dm, densely pubescent proximally, trichomes short-stalked, 2-rayed and simple, to 1 mm, pubescent distally.

usually 1 per caudex branch, arising from center of rosette near ground surface, 2–8(–10) dm, usually glabrous proximally, rarely sparsely pubescent, trichomes simple, to 0.7 mm, glabrous distally.

blade linear to oblanceolate, 2–7(–12) mm wide, margins usually entire, rarely denticulate, ciliate along petiole, trichomes to 1.5 mm, surfaces densely pubescent, trichomes usually short-stalked, 2–5-rayed (rarely some simple), 0.4–0.8 mm.

blade oblanceolate, 3–8(–13) mm wide, margins entire or denticulate, ciliate, trichomes (simple), 0.5–1.2 mm, surfaces sparsely to densely pubescent, trichomes simple, to 0.8 mm, often mixed with short-stalked, 2- or 3-rayed ones, 0.15–0.5 mm.

10–30(–45), often concealing stem proximally;

blade auricles 2–5(–6) mm, surfaces of distalmost leaves pubescent.

6–30(–45), often concealing stem proximally;

blade auricles 1–1.5 mm, surfaces of distalmost leaves sparsely pubescent, sometimes margins ciliate.

12–50(–70)-flowered, usually unbranched.

10–30(–50)-flowered, usually unbranched.

ascending at anthesis;

sepals pubescent;

petals purple, 9–14 × 2–4 mm, glabrous or sparsely pubescent (trichomes abaxially);

pollen ellipsoid.

pendent at anthesis;

sepals pubescent;

petals white, 3–4 × 0.7–1.2 mm, glabrous;

pollen ellipsoid.

usually divaricate-ascending, rarely horizontal, gently recurved or straight, 8–22 mm, pubescent, trichomes subappressed, 2–4-rayed.

reflexed, abruptly recurved at base, otherwise straight, 4–10 mm, glabrous.

usually divaricate-ascending, rarely horizontal, not appressed to rachis, not secund, usually curved, edges parallel, (6–)8–13 cm × 1.5–2.2 mm;

valves glabrous or trichomes relatively few, scattered;

ovules 90–250 per ovary;

style 0.01–0.5 mm.

strongly reflexed, usually appressed to rachis, not secund, straight, edges parallel, 5–9 cm × 1.8–2.5 mm;

valves glabrous;

ovules 46–80 per ovary;

style 0.2–0.8 mm.

uniseriate or sub-biseriate, 1.5–1.7 × 1–1.2 mm;

wing continuous, 0.1–0.2 mm wide.

uniseriate, 1.8–2.1 × 1–1.5 mm;

wing continuous, 0.15–0.25 mm wide.