Flora of North America species comparison

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

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

usually opposite (nodes often appearing leafy, lateral buds producing 2+ pairs of leaves);

sessile or subsessile;

blades strongly 3-nerved from bases, lance-elliptic to oblanceolate, 50–120 × 5–20 mm, bases ± cuneate, margins entire proximally, serrate distally, apices acuminate, faces puberulent or villous, 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 3–3.5 mm.

(4–)5(–6);

corollas (usually pinkish) 2–2.5 mm.

8–10 in 2–3 series, oblong, 1–4 × 0.5–1.5 mm, (bases tapered) apices rounded to acute (not mucronate), abaxial faces pubescent throughout.

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.

2–3 mm;

pappi of 30–40 bristles 3.5–4 mm.

2–3 mm;

pappi of 20–30 bristles 3–5 mm.

= 20, 30, 40.

= 20.