Flora of North America species comparison

usually slightly flexuous, usually glabrous, not glutinous; short shoots present.

strongly flexuous, usually pubescent, not glutinous; short shoots present.

7–65 mm;

stipular spines terete, straight, 2–35(–55) × 0.5–1.4 mm near base;

petiole (3–)6–12(–17) mm, usually sparsely to densely pubescent, hairs erect;

petiolar gland 1, usually medial on petiole, sessile or short-stalked, circular to slightly elongated, 0.2–1 mm, apex depressed;

rachis 10–55 mm;

pinnae 2–6(or 7) pairs, 6–33 mm;

leaflets 8–19 pairs per pinna, blades flat, oblong, 1.6–6.3 × 0.5–1.7 mm, base oblique and obtuse, apex broadly acute to obtuse, surfaces glabrous, glabrate, or pubescent abaxially, glabrous adaxially.

12–45 mm;

stipular spines terete, straight, 5–40(–55) × 0.7–1.5 mm near base;

petiole 3–7 mm, usually densely pubescent, hairs erect;

petiolar gland 1, variable between medial to near basal positions of lowermost pinnae, sessile, elongated to circular, 0.3–2 mm, apex depressed;

rachis 5–40 mm;

pinnae 2–8 pairs, 12–23 mm;

leaflets 11–19 pairs per pinna, blades flat, oblong, 3–5.5 × 0.9–1.5 mm, base oblique and obtuse, apex broadly acute to obtuse, surfaces glabrous.

globose heads, densely flowered, 6–10 mm diam., solitary or clusters of 2–5 on short shoots;

involucre at base of head (not obvious).

globose heads, densely flowered, 6–9 mm diam., solitary or clusters of 2–5 on short shoots;

involucre at base of head (not obvious).

12–36(–45) mm.

12–36 mm.

bright yellow;

calyx 1.1–1.8 mm, glabrous;

corolla 1.9–2.8 mm, glabrous;

filaments yellow, 3.5–5.5 mm.

pale yellow;

calyx 1.1–1.8 mm, pubescent;

corolla 1.5–2.4 mm, pubescent;

filaments yellow, 3.5–4.5 mm.

oblong, nearly terete or elliptic in cross section, 30–170 × 9–18 mm, constricted or not between seeds.

linear, elliptic in cross section, 65–150 × 5–9 mm, constricted between seeds.

biseriate, uniseriate, or irregularly arranged.

uniseriate.

= 26.