Lupinus nanus
Trans. Hort. Soc. London, ser. 2, 1: 409, plate 14, fig. 2. 1835.
Herbs, annual, 1–6 dm, pubescent. Cotyledons deciduous, petiolate. Stems ascending or erect, branched or unbranched. Leaves cauline; petiole 2–8.5 cm; leaflets 5–7(–9), blades 10–40 × 1–12 mm, adaxial surface pubescent. Peduncles 2–15 cm; bracts deciduous, 4–12 mm. Racemes 4–40 cm; flowers usually whorled, sometimes spirally arranged distally. Pedicels 2.5–7 mm. Flowers 6–15 mm; calyx 4–8 mm, lobes ± equal, adaxial lobe deeply cleft; corolla usually blue, rarely light blue, lavender, pink, white, banner spot white, upper keel margins ciliate near apex, banner as wide as or wider than long. Legumes 2–4 × 0.4–0.7 cm, pubescent. Seeds 4–12. 2n = 48.
Phenology: Flowering late winter–spring.
Habitat: Open or disturbed areas.
Elevation: 0–1300 m.
Distribution
Calif., Oreg., Wash.
Discussion
Lupinus nanus is a highly variable complex. Plants in northern California and southwestern Oregon, referred to as L. vallicola, have smaller flowers and may be confused with L. bicolor.
Lupinus nanus occurs throughout California except in the Great Basin and desert regions and northward to Washington.
Selected References
None.