Astragalus lemmonii, the Lemmon’s milkvetch, is a rare plant of eastern California. It is a member of the bean family, the Leguminosae (a.k.a. Fabaceae), and specifically a member of the subfamily Papilionoideae (a.k.a. Faboideae). The genus Astragalus is a large genus within this family; members of this genus are known as milkvetches or locoweeds. Close relatives of this particular species include Astragalus peckii and Astragalus lentiformis.