Lupinus andersonii
Lupinus arboreus
Anderson's lupine
coastal bush lupine, tree lupine, yellow bush lupine
erect or ascending, branched.
ascending or erect, branched, woody.
cauline;
stipules not leaflike, green to silvery, 3–15 mm;
petiole 2–6 cm;
leaflets 6–9, blades 20–60 × 5–10 mm, adaxial surface pubescent.
cauline;
stipules 8–12 mm;
petiole 2–3(–6) cm;
leaflets 5–12, blades 20–60 × 3–10 mm, adaxial surface glabrous.
open, 2–23 cm;
flowers ± whorled.
10–30 cm;
flowers whorled or not.
1–8.5 cm;
bracts deciduous, 2–10 mm.
4–10 cm;
bracts deciduous, 8–10 mm.
1.5–5 mm.
4–10 mm.
9–12 mm;
calyx bulge or spur 0–1 mm, abaxial lobe 2 or 3-toothed, 3–8 mm, adaxial lobe 2-toothed, 5–7 mm;
corolla usually light blue or lavender to purple, rarely white, banner patch white turning purple, banner glabrous abaxially, keel upcurved, glabrous, banner ovate, wings wide, covering keel tip.
14–18 mm;
calyx bulge or spur 0–1 mm, abaxial lobe entire, 5–7 mm, adaxial lobe 2-toothed, 5–9 mm;
corolla usually yellow, rarely lilac to purple, banner patch darker or not or white, banner glabrous abaxially, lower keel margins glabrous, adaxial margin ciliate from claw to tip.
2–4.5 cm, silky.
4–7 cm, hairy.
deciduous, petiolate.
deciduous, petiolate.
4–6, brown, mottled tan, 4–6 mm.
8–12, black to tan, often striped lighter, 4–5 mm.
= 48.
Lupinus andersonii
Lupinus arboreus
Lupinus andersonii is found widely in regions of the Sierra Nevada in California and western Nevada plus adjacent areas of southern Oregon. The erect branching with puberulent leaflets and a banner that is glabrous abaxially distinguish it from L. angustiflorus, L. apertus, and L. padrecrowleyi, which have pubescence at least on the abaxial crest of the banner. According to P. A. Munz (1959), L. egressus C. P. Smith may be of hybrid origin (L. fulcratus × L. andersonii).
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Lupinus arboreus is known from the central California coast southward to northern Baja California; it was introduced as a sand binder and has become naturalized in northern California, Oregon, Washington, and southern British Columbia.
Lupinus arboreus grades into L. rivularis in the North Coast of California. Plants with yellow petals and sweet-smelling flowers are widely cultivated as a sand binder. Hairier plants from the western San Francisco Bay area with yellow banners and blue wings have been called var. eximius; plants with glabrous leaflets and purple petals have been called L. propinquus. Lupinus arboreus hybridizes with L. littoralis and probably other species. Seeds of L. arboreus species are toxic.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
- 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
