The choicest milkvetch in the immediate Denver area is this tiny cushion plant: pretty much restricted to the foothill rock outcrops near Denver up to central Wyoming. It can make huge cushions, like vegetable sheep, in parts of it range. It is one of a half dozen "Orophaca": this has been used as a sectional name and also an attempted generic. They are the densest, most wonderful cushion plants in the genus--centered in Wyoming and northern Colorado. Astragalus gilviflorus shown in the other post is in this group (the least cushiony of all). The biggest cushions are formed by Astragalus hyalinus, and those can be three feet across and very hummocky. Alas, it has inconspicuous lilac flowers. The real queens of the Orophaca section are A. tridacylicus, A. sericoleucus and A. aretioides, all of them forming dense cushions studded with tiny pink flowers: they are distinguished by all sorts of minutiae, and all three are worth growing. This one was in my old garden on Eudora: must get it back! The yellow is Eriogonum ovalifolium from the Uinta Basin. Penstemon thompsoniae in front.