Flora of North America species comparison

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

(from short caudices) single, branched distally, puberulent throughout (lateral buds often develop fertile and infertile branches).

usually opposite (distal sometimes alternate, lateral buds dormant or producing 1 pair of leaves); simple, sessile or subsessile;

blades ± 3-nerved distal to bases, elliptic to lance-elliptic, (30–)50–70 × 5–25 mm (lengths mostly 2–5 times widths), bases narrowly cuneate, margins usually serrate, apices acute, faces puberulent or villous, densely gland-dotted.

opposite (proximal) or alternate (lateral buds dormant or producing 1 pair of leaves);

sessile;

blades (often pinnately or ternately lobed) or lobes pinnately nerved, linear, 20–80 × 0.5–2.5(–4) mm, bases cuneate, margins entire, apices acuminate, faces puberulent, gland-dotted.

5;

corollas 2.5–3 mm.

5;

corollas (sometimes with purple throats) 2.5–3 mm.

7–10 in 2–3 series, elliptic, 1–3 × 0.5–1 mm, apices rounded to acute (not mucronate), abaxial faces puberulent, gland-dotted.

7–10 in 2–3 series, (sometimes purple) elliptic to oblong, 1–3 × 0.5–0.8 mm, (margins hyaline) apices acuminate and mucronate, abaxial faces puberulent (mostly on midveins), usually gland-dotted.

in corymbiform arrays.

in paniculiform arrays.

1.5–2 mm;

pappi of 30–40 bristles 2.5–3 mm.

1–1.7 mm;

pappi of 20–30 bristles 3–3.5 mm.

= 20.

= 20.