Flora of North America species comparison

(from tuberous rhizomes) multiple, densely branched distally, puberulent throughout.

(from short rhizomes) single, branched distally, puberulent.

usually opposite (distal sometimes alternate);

sessile or subsessile;

blades 3-nerved distal to bases, oblanceolate, 20–80 × 5–10(–20) mm, bases cuneate, margins serrate proximally, entire distally, apices acute, faces puberulent (abaxial), glabrous or glabrate (adaxial), gland-dotted.

opposite;

subsessile or petiolate;

blades palmately 3(–5)-lobed (at least larger proximal, lobes relatively broad), blades (or lobes) lanceolate to lance-ovate, 50–100 × 20–40 mm, margins serrate, apices rounded to acute, faces puberulent, gland-dotted.

5;

corollas 2–4 mm.

(4–)5(–6);

corollas (usually pinkish) 2–2.5 mm.

7–10 in 1–2 series, oblanceolate, 1–3 × 0.2–0.5 mm, apices rounded, abaxial faces puberulent, gland-dotted.

8–10 in 2–3 series, oblong, 4.5–6 × 1.5–2 mm, apices rounded, abaxial faces puberulent, gland-dotted.

in corymbiform arrays.

in dense, corymbiform arrays.

1–2 mm;

pappi of 20–30 bristles 2.5–3 mm.

2–3 mm;

pappi of 20–30 bristles 3–5 mm.

= 20, 30, 40.

= 20.