Flora of North America species comparison

fusiform, fascicled, thickened, epidermis splitting or peeling near base.

erect to spreading, terete or sometimes ridged, 60–250(–400) cm, densely branched, densely villous to glabrate, especially near base.

subterete or somewhat angled, with narrow raised lines or wings decurrent from leaf axils, 40–150 cm, well branched in distal 1/2, glabrous or sparsely to densely strigillose.

stipules deltate, 0.5–0.8 × 0.6–0.7 mm, fleshy;

petiole 0–1 cm;

blade linear to oblong or oblanceolate, sometimes narrowly ovate, 0.7–14.5 × 0.1–4 cm, base tapered, margins entire, apex acute to acuminate, surfaces ± densely villous or strigillose;

bracts not or scarcely reduced.

stipules narrowly deltate, 0.05–0.2 × 0.05–0.1 mm;

petiole 0.1–0.3(–0.7) cm;

blade lanceolate-elliptic, (0.6–)2–12 × (0.3–)1–1.5(–2.5) cm, base attenuate, margins entire, apex acute, surfaces strigillose throughout or glabrate with strigillose veins;

bracts often reduced and more linear.

open, leafy racemes, flowers solitary in axils, presentation often radial;

bracteoles ovate, 3–8 × 1.4–4 mm, apex acuminate, attached near base of ovary.

leafy racemes, flowers solitary in leaf axils;

bracteoles linear-lanceolate, 1–2.5 mm, margins entire, apex acute or subacuminate, glabrous or with scattered hairs, attached near base of ovary.

sepals lanceolate to ovate, (6–)8–13 × 3–7 mm, apex acuminate, surfaces strigillose adaxially;

petals bright yellow, fan-shaped, (5–)10–20 × 5–20 mm, apex sometimes shallowly notched;

stamens 8 in 2 subequal series, yellowish white, filaments spreading, 4–6 mm, anthers oblong, 2.5–5 × 1–2 mm;

pollen shed in tetrads or sometimes polyads;

ovary cylindric, 4-angled, sometimes slightly twisted, 8–22 × 1–3 mm;

nectary disc elevated 0.4–0.5 mm on ovary apex, 1–2.4 mm diam., with 4 white-pubescent sunken lobes opposite petals;

style 2.5–3.5 mm, stigma capitate-globose, 1.8–3.5 × 2.5–3.5 mm, surrounded by anthers and pollen shed directly on it.

sepals narrowly ovate-deltate, (6–)6.5–9.5 × 4–6.5 mm, margins entire, apex acute to obtuse, surfaces strigillose, sometimes mixed with villous hairs, or glabrate;

petals cordate, 10–14 ×8–12 mm, base attenuate, apex emarginate;

filaments opaque white, awl-shaped, 1–3 mm, anthers 1–1.7 × 0.6–0.8 mm;

ovary subcuboid to globose, 2.5–4 ×2.5–3.5 mm;

nectary disc slightly elevated on ovary apex, 0.8–1.5 mm diam., 4-lobed, ringed with soft, curly hairs or glabrous;

style 1.5–2.4 mm, glabrous, stigma light yellow, capitate to hemispherical, 1–1.3 × 1.4–2 mm, shallowly 4-lobed, not or scarcely exserted beyond anthers.

cylindric to clavate-cylindric, subterete to ± 4-angled, 17–50 × 2.5–8 mm, thin-walled, irregularly dehiscent by 4–8 linear valves splitting from apex, short-villous, pedicel 5–25 mm.

subcuboid to squarish globose, 4–6(–7) × 4–6 mm, 4-angled and 4-winged, wings 0.3–1.5 mm wide, pedicel 2–7 mm.

in several indistinct rows per locule, broad-cylindric with rounded ends, 0.6–0.9 × 0.5–0.8 mm, raphe inflated and nearly equal to seed body.

light brown, oblong to reniform, 0.5–0.8 × 0.2–0.4 mm, surface cells elongate transversely to seed length.

= [16], 32, 48.

= 16.