Astragalus whitneyi, the balloonpod milkvetch, is a mid to high elevation tufted perennial. There are five varieties listed, Astragalus whitneyi var. confusus, var. lenophyllus, var. siskiyouensis, var. whitneyi and var. sonneanus. Found on desert mountains along the eastern escarpment of the Cascade/Sierra Nevada crest. Starting in Washington going south to northeastern California, western Nevada and continuing east to southwestern Idaho.
As the common name implies the pods are inflated balloons. The tan/golden pods are mottled with splotches of red through purple. The flowers come in white through purple depending on the variety and are held in clusters, splayed out around the tufts of stems. They grow six to eight inches tall with fuzzy green or gray leaves. As the thin walled pods mature they loose their splotches and turn a shiny golden color. Detaching they drift with the wind, eventually shattering, disbursing their seed.
I grow Astragalus whitneyi var. lenophyllus. The flowers on this variety are white.
http://www.calflora.org/cgi-bin/species_query.cgi?where-taxon=Astragalus...
http://www.calflora.org/cgi-bin/species_query.cgi?where-taxon=Astragalus...
http://www.pnwflowers.com/flower/astragalus-whitneyi
http://plants.usda.gov/java/profile?symbol=ASWH
http://science.halleyhosting.com/nature/basin/5petal/pea/astragalus/ball...
