Flora of North America species comparison

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

(from short caudices) multiple, branched distally, puberulent throughout.

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.

opposite (proximal) or alternate (nodes often appearing leafy because of development of leaves on lateral buds without axis elongation);

sessile;

blades (often ternately lobed) or lobes linear, 5–100 × 0.2–0.5(–1) mm, bases ± cuneate, margins entire (strongly revolute), apices rounded to acute, faces glabrate, gland-dotted.

(4–)5;

corollas 4–4.5 mm.

5;

corollas 2–2.5 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.

8–10 in 2–3 series, oblong, 0.5–2.5 × 0.2–0.5 mm, apices acuminate and mucronate, abaxial faces glabrous or glabrate, not or little, if at all, gland-dotted.

in corymbiform arrays.

in dense, paniculiform arrays.

2.5–3.5 mm;

pappi of 40–50 bristles 3.5–4.5 mm.

1–1.7 mm;

pappi of 20–30 bristles 2–2.5 mm.

= 20.