Flora of North America species comparison

prostrate or decumbent.

erect.

mostly alternate;

petioles 15–30(–45+) mm;

blades rounded-deltate to ovate or obovate, 20–45(–70+) × 10–25(–50+) mm overall, not lobed or 1–2(–3)-pinnately lobed, bases cuneate, ultimate margins entire or toothed, abaxial and adaxial faces strigillose to sericeous.

opposite (distal sometimes alternate);

petioles 0;

blades lanceolate or lance-elliptic to lance-oblong or oblanceolate, 20–50(–70+) × 8–12(–25+) mm, rarely ± pinnately lobed (lobes ± deltate), bases cuneate (then rounded), margins entire or toothed, abaxial faces densely strigose (silvery gray), adaxial faces strigillose.

peduncles 0.5–2 mm;

involucres shallowly cup-shaped, 4–6+ mm diam., strigillose;

florets 8–25(–50).

peduncles 1–4+ mm;

involucres cup-shaped (sometimes with black nerve in each lobe), 3–4+ mm diam., strigillose;

florets 8–18+.

clustered, proximal to staminates;

florets 1.

clustered (in axils), proximal to staminates;

florets 1(–2).

bodies fusiform to ± pyriform, 4–7+ mm, ± strigillose to pilosulous, spines 8–16+, scattered, stoutly conic or flattened- to triquetrous-subulate, 0.5–1.5+ mm, tips straight.

bodies ± pyriform to ± globose, 2–3+ mm, glabrous or strigose, spines (1–)3–5+, scattered, stoutly conic, 0.4–0.8+ mm, tips straight (often each with black nerve).

= 36.

= 72.