Flora of North America species comparison

all or mostly opposite (distal sometimes alternate);

blades ± lance-linear (lengths 10–15 times widths), 9–12(–20+) × 0.6–1.2(–1.5+) cm, bases rounded, margins obscurely toothed to subentire, apices ± attenuate, faces ± scabrellous.

all or mostly alternate (proximal sometimes opposite);

blades lance-ovate or lance-elliptic to lance-linear, 5–12(–22+) × 1–6(–12+) cm, sometimes pinnately lobed, bases ± cuneate, ultimate margins usually coarsely toothed to subentire, sometimes sinuate, apices acute, faces ± scabrellous to strigillose.

± hemispheric to saucerlike, 11–15+ mm diam.

± obconic to turbinate, 3–5 mm diam.

12–13;

laminae 15–25+ mm.

(1–)2–3(–7);

laminae 3–4(–7+) mm.

60–100+;

corollas yellow.

8–12(–15);

corollas ochroleucous or white.

18–24+ in 2–3 series, ± erect to spreading, linear to lance-linear, 5–15+ mm.

8–12+ in 1–2 series, ± erect, spatulate to oblanceolate, 2.5–5(–7) mm.

borne singly or 3–5+ in loose, corymbiform arrays.

(20–)60–100+ in corymbiform to paniculiform arrays.

dark brown, oblanceolate to elliptic, 7 mm, faces glabrous;

pappi 0–0.5 mm.

dark brown to blackish, oblanceolate, 3.5–5+ mm, faces ± scabrellous;

pappi 1.5–3+ mm.

= 34.

= 32, 34.