Lupinus arbustus
Lupinus lepidus
grassland lupine (ssp. neolaxiflorus), long-spur lupine, Montana lupine (ssp. pseudoparviflorus), spur lupine
desert lupine, Donner Lake lupine, dwarf lupine, Lobb's lupine, Pacific lupine, prairie lupine, prostrate lupine, stool lupine, tidy lupine
erect, ascending, or decumbent, branched.
acaulescent or prostrate to ± erect, unbranched or branched.
cauline and basal;
stipules 4–9 mm;
petiole 2–16 cm;
leaflets 7–10(–13), blades 20–70 × 3–15 mm, adaxial surface strigose.
usually basal, sometimes cauline present;
stipules 3–25 mm;
petiole 2–13 cm;
leaflets 5–8, blades 5–40 × 3–7 mm, surfaces pubescent.
open, 3–18 cm;
flowers whorled.
dense, 3–20 cm, not exceeding to exserted beyond leaves;
flowers whorled, usually crowded.
2–5 cm;
bracts deciduous, 3–6 mm.
2–13 cm;
bracts usually persistent, 4–15 mm.
1–7 mm.
0.4–3 mm.
8–14 mm;
calyx spur distinct, 1–3 mm, abaxial lobe 3-toothed, 2.5–5 mm, 1–3 mm, adaxial lobe 2-toothed, 2–4 mm;
corolla blue, purple, pink, white, or yellowish, banner patch white, yellowish, or absent, banner hairy abaxially, wings with dense hair patch outside near tip, lower keel margins glabrous, adaxial margin ciliate.
6–13 mm;
calyx bulge or spur 0–1 mm, abaxial lobe entire or 3-toothed, 4–7 mm, adaxial lobe entire or 2-toothed, 3–7 mm;
corolla pink, violet, or blue, banner glabrous abaxially, lower keel margins glabrous, adaxial margin ciliate.
2–3 cm, silky.
1–2 cm, hairy.
deciduous, petiolate.
deciduous, petiolate.
3–6, tan, 5–6 mm.
2–6, ± mottled tan or green to brown, 2–4 mm.
Lupinus arbustus
Lupinus lepidus
Lupinus arbustus is known from the Cascade and Klamath ranges, San Gabriel Mountains, Sierra Nevada, and the Great Basin area in California; Owyhee Desert in Idaho and Oregon; eastern Washington and western Montana; and western Juab and Tooele counties, Utah.
Lupinus arbustus is separated from the argenteus group by the presence of hairs on the corolla wings. Recognition of subspecies and varieties of this already complex species leads to precarious separation among taxa.
Lupinus variegatus A. Heller (1912, not Poiret 1814) is an illegitimate name that pertains here.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Varieties 10 (10 in the flora).
Dwarf perennial lupines are usually characterized by a cespitose habit, persistent inflorescence bracts, banners that are glabrous abaxially, and ciliate keel petals. The history of the taxonomy of this group was discussed in detail by B. J. Cox (1972), R. C. Barneby (1989), and K. A. Weitemier (2010). Barneby gave justification for his conservative treatment of this taxon, which is generally followed here. Genetic analysis in lupines has shown little separation, according to Weitemier, but he suggested that there is good evidence to retain these variations as varieties, following Barneby, rather than elevating them to species level.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
1. Racemes not exceeding leaves, or only partially so. | → 2 |
2. Banner recurved, reflexed, 3+ mm wide. | var. aridus |
2. Banner not or scarcely recurved, overhanging wings, 2.5–3 mm wide. | → 3 |
3. Stems present and branched; leaves basal and cauline; racemes loose; pedicels 2.5–. | var. cusickii |
3. Stems very short or absent, densely tufted; leaves basal; racemes dense; pedicels 0.4–. | → 1 |
1. 5 mm. | var. utahensis |
1. Racemes entirely exserted beyond leaves. | → 4 |
4. Leaves clustered near base (appearing ± basal); herbs appearing acaulescent or shortly caulescent. | → 5 |
5. Flowers 9–12 mm; leaflet blades 10–20 mm; rare, only from Mt. Ashland, Oregon. | L. lepidus var ashlandensis |
5. Flowers 6–9(–10) mm; leaflet blades 5–30 mm; British Columbia southward to California, eastward to Idaho, Nevada. | → 6 |
6. Racemes ± dense, 2–8 cm; herbs to 1 dm; leaflet blades 5–10 mm; elevation (1600–)2000–3500 m. | var. lobbii |
6. Racemes elongate, (2–)4.5–11(–15) cm; herbs 1.2–3.5 dm; leaflet blades 10–30 mm; elevation 1000–2500 m. | var. sellulus |
4. Leaves usually spread along stems or at least with some tufts of cauline leaves; herbs usually strongly caulescent (except stems short or absent in var. culbertsonii). | → 7 |
7. Flowers 10–14 mm; Alberta, British Columbia, Alaska, Oregon, Washington. | var. lepidus |
7. Flowers 7–11.5(–12) mm; California, Nevada. | → 8 |
8. Racemes dense, (5–)12–30 cm; flowers in 9–12 whorls, dense; leaves cauline; elevation (300–)1500–2500(–3200 m). | var. confertus |
8. Racemes usually open, 2–10(–12) cm; flowers in (2 or)3–7 whorls, ± well spaced; leaves basal and cauline; elevation 1900–4000 m. | → 9 |
9. Leaflet blades usually 10–30 mm; flowers (9–)10–11.5 mm; elevation 1900–3600 m. | var. culbertsonii |
9. Leaflet blades usually 5–15(–30) mm; flowers usually 7–9(–12) mm; elevation 2300–4000 m. | var. ramosus |
- Local floras:
BC, 
CA, 
OR, 
WA - Local Web sites: CalFlora, CalPhotos,
Flora NW, 
PNW Herbaria, Turner Photog. 
WildflowerSearch
iNaturalist (observations)
USDA Plants Database- LBJ Wildflower Center
- SEINet
- Plants of the World Online
- Encyclopedia of Life
- Wikipedia
- Google Image Search
- Local floras: BC, CA, OR, WA
- Local Web sites: CalFlora, CalPhotos, Flora NW, PNW Herbaria
- WildflowerSearch
- iNaturalist (observations)
- USDA Plants Database
- LBJ Wildflower Center
- SEINet
- Plants of the World Online
- Encyclopedia of Life
- Wikipedia
- Google Image Search
