Astragalus tenellus Nutt.
Pulse milk-vetch is perennial from a branched base atop a long woody taproot. Leaves are 2-3 inches long and pinnate, like two combs held back-to-back, because of 11-21 narrow leaflets up to an inch long. The 1/2 inch-long flowers are like those of the pea, only white or yellowish, with purplish keels and banner petals. Flowers are found in loose clusters (racemes) of 5-15 that occur mostly near the top of the plant. Mature fruits (legumes) about 1/2 inch long hold the brown, purple-spotted seeds. Blooms in July on rocky or gravelly native prairie. Grows on dry habitats on a great variety of of substrates from barren knolls in sagebrush valley up through pinyon-juniper woodland into mountains. Found across southeastern Idaho.
The plant is not listed among the milk-vetches that can poison livestock, and may have some forage value, as more plants seem to occur where grazing is light or moderate.