Description

Key Characters:

Growth Form: Annual herbs.

Stems: Stems spreading, ascending, or erect, up to 7.5 dm long, striate, appressed short–pubescent, taproot with slender branches, nodules often present.

Roots:

Leaves: Leaves compound (trifoliolate). Alternate. Leaflets oblanceolate to narrowly obovate. Leaflets 0.9–2.8 cm long, 0.3–0.8 cm wide. Apex rounded, usually retuse. Base cuneate. Upper surfaces glabrous or sparsely pubescent; lower surfaces appressed short–pubescent. Margins entire. Veins 5–10 on each side of midvein. Petioles 4–18 mm long. Stipules linear–triangular, 1–4 mm long.

Flowers: Flowers in racemes, flowers 5.2–9.5 mm long, 6–21 in terminal or leaf–opposed, somewhat lax inflorescences, rachis 2–15 cm long (incl. peduncle), bracts linear–triangular, 1–2 mm long, ascending, usually persistent. Flowers papilionaceous; bracteoles absent or minute at base of calyx, linear–triangular. Calyx appressed short–pubescent, the tube 1.1–2.1 mm long, the lobes 3.3–3.8 mm long, lateral lobes distinct at apex. Calyx slightly bilabiate, the lobes shorter than to longer than the tube. Petals yellow with lines near base, standard 5–7 mm long, 7–8 mm wide, wings oblong, 5.5–6 mm long, 2–2.5 mm wide, keel petals with twisted beak prolonged, margins ciliate. Stamens 10, connate into a tube, the tube split at least at base on the upper side; anthers dimorphic, alternately long (and basifixed) and short (and versatile). Elongated anthers 1.1–1.7 mm long, short ones 0.2–0.3 mm long. Ovary superior.

Fruit: Pods pale brown at maturity; 0.6–2.5 cm long; nonstipitate; appressed short–pubescent or spreading pubescent. Seeds ca. 10 per pod; brown; 3.5–4 mm long; smooth.

Ploidy: 2n = 8; 16; 32

Habitat:

Elevation Range: