Herbs or subshrubs, perennial, to 2 dm, matted or tufted, silvery-silky. Cotyledons deciduous, petiolate. Stems prostrate, branched, base ± woody. Leaves cauline, clustered near base; stipules 2–5 mm; petiole 1–5(–6) cm; leaflets 5–10, blades 3–20 × 2–6 mm, adaxial surface pubescent. Peduncles 1–3(–8) cm; bracts deciduous, 3–5 mm. Racemes dense, 1–10 cm; flowers whorled. Pedicels 1–3(–4) mm. Flowers 4–11 mm; calyx bulge or spur 0–1 mm, abaxial lobe entire or 3-toothed, 4–6 mm, adaxial lobe 2-toothed, 4–7 mm; corolla blue to violet, banner patch white or yellow, banner glabrous or densely hairy abaxially, keel straight, abaxial margins glabrous, adaxial margin glabrous or ciliate. Legumes 1–2 cm, silky. Seeds 3 or 4, mottled tan, brown, 3–4 mm.
Distribution
w United States.
Discussion
Varieties 3 (3 in the flora).
Selected References
None.
Lower Taxa
Key
| 1 | Banner silky abaxially, keel strongly ciliate. | Lupinus breweri var. grandiflorus |
| 1 | Banner glabrous abaxially, keel glabrous. | > 2 |
| 2 | Flowers 6–9 mm; leaflet blades 6–20 mm. | Lupinus breweri var. breweri |
| 2 | Flowers 4–6(–7) mm; leaflet blades 3–5 mm. | Lupinus breweri var. bryoides |