Lupinus argenteus Pursh var. depressus (Rydb.) C.L. Hitchc.
Annotated by Hannah Marx, 10 Dec 2013. Sources: Flora of PNW.

Idaho: Custer County: Idaho: Sawtooth National Forest: White Cloud Mountains: Castle Peak: summit down southwest slope to treeline Elev. 11815 ft.
44.039758° N, 114.588008° W
Datum: WGS 84. Uncertainty: 348 meters. Coordinate Source: Digital Map.
Very loose talus, mostly bare of plants except for in boulder outcrops and exposed soils and cracks. Composed of both limestone and granite. Treeline; Pinus albicaulis, near end of talus slope on south face = 9860 ft., 44.03274ºN, 114.5878ºW. Summit Assoc.: Selaginella, Draba sp., grasses, Polemonium viscosum, Arabis sp. Dominant Assoc. on slope: Minuartia obtusiloba, Oxyria digyna, Antennaria alpina. Just at treeline; blue flowers, hairy. Leaf tissue in silica gel at ID. Phenology: Flowers.

Hannah Marx 2013-192, Jul 25, 2013
With Chris Lundy (Sawtooth Mountain Guides)
ID, Accession: 169082, Barcode: ID169391