Published In: Reports of explorations and surveys: to ascertain the most practicable and economical route for a railroad from the Mississippi River to the Pacific Ocean, made under the direction of the Secretary of War 2(1): 120, pl. 3. 1857. (Pacif. Railr. Rep.)

• Astragalus beckwithii var. beckwithii  = Astragalus beckwithii Torr. & A. Gray
• Astragalus beckwithii var. purpureus M.E. Jones  = Astragalus beckwithii Torr. & A. Gray
• Astragalus beckwithii var. sulcatus Barneby  = Astragalus beckwithii Torr. & A. Gray
• Astragalus beckwithii var. weiserensis M.E. Jones  = Astragalus beckwithii Torr. & A. Gray