Flora of North America species comparison

glabrous.

glabrous.

basal and proximal cauline 1-nerved, linear to linear-lanceolate, 70–150 × 1–2.5 mm, abruptly or gradually reduced on distal 1/2 of stems, essentially glabrous (margins sometimes sparsely ciliate).

basal and proximal cauline 1-nerved, narrowly oblanceolate, (50–)90–150 × (2–)4–9(–12) mm wide, usually abruptly, sometimes gradually, reduced distally, glabrous or sparsely pilose (abaxially), gland-dotted (proximal margins sparsely pilose-ciliate).

0.

0 or (ascending) mostly 2–12 mm.

cylindro-turbinate, 9–12 × 3.5–5 mm.

campanulate-cylindric, (6–)7–9 × 3.5–4.5(–5) mm.

3–4(–5);

corolla tubes glabrate inside.

7–10(–12);

corolla tubes pilose inside.

in 2–3 series, (often dark purple in anthesis) oblong-lanceolate to lanceolate-triangular, weakly unequal, essentially glabrous, margins without hyaline borders, sometimes sparsely ciliate, apices acute to acute-attenuate (sometimes with narrow tips).

usually in 3–5(–6) series, in 5–6(–7) series in largest heads, ovate-triangular to oblong, unequal, glabrous, margins with narrow, hyaline borders (lacking at apices), sometimes sparsely ciliolate, apices acute to obtuse-angled (with thickened, not markedly involute, apicula).

(closely spaced, stems obscured) in dense, (cylindric) spiciform arrays.

in loose, racemiform to spiciform arrays (not secund, internodes 6–20 mm).

4.5–6 mm;

pappi: lengths ± equaling corollas, bristles plumose.

(2–)3–4 mm;

pappi: lengths ± equaling corollas, bristles barbellate.

globose or subglobose.

mostly globose.

= 20.