kingdom: Plantae >
subkingdom: Pteridobiotina Britton & Brown >
phylum: Tracheophyta >
class: Magnoliopsida >
order: Fabales Bromhead >
family: Fabaceae >
genus: Astragalus L. >
species: Astragalus flavus Nutt. >
Arizona , Colorado , Nevada , New Mexico , Utah , Wyoming