Astragalus parryi (Parry's Milk Vetch)

Order Fabales, Family Fabaceae, Genus Astragalus

In my opinion, this is the prettiest Astragalus. It likes full sun and open woods. After a detailed search, it turns out that iNaturalist has the best collection of photos. Northwest Wildflowers has more information. Apparently, A. parryi has a limited occurance, growing only in Colorado and Wyoming.