Flora of North America species comparison

(from short caudices or stout rhizomes) single, sparsely branched distally, pubescent throughout.

(from short caudices or rhizomes) single, sparsely branched distally, 5–10+ dm, glabrous or glabrate proximally, puberulent distally (among heads).

usually opposite (distal sometimes alternate);

sessile;

blades ± 3-nerved or pinnately nerved, elliptic to oblanceolate, 30–120 × 10–40 mm (lengths mostly 3–4 times widths), bases narrowly cuneate (sometimes oblique), margins subentire, serrate, or serrulate, apices rounded to acute, faces setulose (denser on midribs and veinlets) to glabrate, usually gland-dotted.

usually opposite (distal sometimes alternate); simple, sessile;

blades pinnately nerved, lanceolate to oblong, 70–150+ × 10–30 mm (lengths mostly 2–5 times widths), bases truncate to somewhat rounded, margins serrate, apices narrowly acute to acuminate, faces glabrate (scattered, fine hairs), gland-dotted.

(4–)5;

corollas 4–4.5 mm.

5;

corollas 3–3.5 mm.

9–15 in 2–4 series, linear, 1.5–9 × 0.6–1 mm, apices acuminate to attenuate, sometimes mucronate, abaxial faces pubescent throughout, gland-dotted.

10–15 in 2–3 series, elliptic to oblong, 2–5 × 0.5–1.5 mm, apices rounded to acute (not mucronate), abaxial faces villous to puberulent, gland-dotted.

in corymbiform arrays.

in corymbiform arrays.

2.5–3.5 mm;

pappi of 40–50 bristles 3.5–4.5 mm.

2–3 mm;

pappi of 30–40 bristles 3–4 mm.

= 20, 30.