Flora of North America species comparison

, branches, and twigs densely covered with conspicuous lenticels, glabrescent; short shoots absent.

and twigs spreading, glabrous or hairy, without resting buds, with or without short shoots (brachyblasts), bark smooth to rough, crown usually rounded.

stipules to 1 mm, not spiny, caducous, hard, triangular-subulate, glabrous;

petiole 0.4–1.5(–2) cm, shorter than rachis, subglabrous;

pinnae 2(or 4), rachis 8–13 mm;

leaflets 2 per pinna, blades obovate to oblanceolate-elliptic, 3–8.5(–9) × 1.5–5(–7) cm, base oblique, margins entire, usually revolute, apex rounded with a very small mucro, brochidodromous venation conspicuous on both surfaces, main vein subcentral, surfaces glabrous.

alternate, even-bipinnate, not sensitive to touch;

stipules present; petiolate;

pinnae 2(or 4), opposite, extrafloral nectaries present between pinnae and leaflets;

leaflets 2, opposite, blade margins entire, surfaces glabrous or glabrescent.

pedunculate, 15–50+-flowered, axillary, heads or spikes, forming pseudoracemes;

bracts absent or present, glandular.

primary peduncle flattened, axis to 7 cm, glabrescent, secondary peduncles (2.5–)4.5–6 cm, glabrous;

bract absent.

calyx campanulate or tubular, 1.5–2 mm, lobes 0.5 mm, glabrescent;

corolla campanulate or funnelform, to 5.5 mm, lobes 4 or 5;

stamens white, dirty cream, or pink, tube to 3–3.5 mm;

ovary 1–1.5 mm, glabrous, stipe to 1.5 mm.

mimosoid, sessile, valvate;

calyx greenish, campanulate or tubular, lobes 5 or 6, calyx and corolla connate;

corolla greenish;

stamens 15+, monadelphous, connate proximally into a tube, filaments white or pinkish;

anthers dorsifixed.

legumes, sessile or stipitate, turgid, recurved to coiled, oblong, without thickened margins, dehiscent, leathery, rugose to reticulate, hairy or glabrous; ± constricted between seeds.

slightly recurved to 1-coiled (especially at dehiscence), slightly constricted between seeds, 8–20 × 1–1.5 cm, margin not evident, base attenuate, apex cuspidate without beak, glabrous, veins faint;

without stipe.

on secondary peduncles 15–30-flowered, sometimes elongated.

6–12, usually not pendulous, 6–9 × 5–6 mm;

aril red, covering proximal 1/3 of seed.

5–12[–16], elliptic to ovate or obovate in outline, strongly biconvex;

aril present.

triangular, 0.8 mm, puberulous abaxially.

= 13.

= 26.