| Astragalus emoryanus (Rydb.) Cory, 1936 |
| Astragalus emoryanus var. terlinguensis (Cory) Barneby, 1956 |
| Astragalus ervoides Hook. & Arn., 1840 |
| Astragalus ervoides var. ervoides Hook. & Arn., 1840 |
| Astragalus ervoides var. maysillesii Barneby, 1964 |
| Astragalus erythrostachys Ulbr., 1902 |
| Astragalus esperanzae M.E. Jones, 1923 |
| Astragalus fastidiosus Greene, 1886 |
| Astragalus fastidius (Kellogg) M.E. Jones, 1898 |
| Astragalus fendleri (A. Gray) A. Gray, 1853 |
| Astragalus filipes Torr. & A. Gray, 1866 |
| Astragalus filipes var. residuus Jeps., 1925 |
| Astragalus flexuosus Douglas ex G. Don, 1832 |
| Astragalus flexuosus var. greenei (A. Gray) Barneby, 1960 |
| Astragalus francisquitensis M.E. Jones, 1895 |
| Astragalus francisquitensis var. lagunensis (M.E. Jones) M.E. Jones, 1902 |
| Astragalus galegoides Nutt., 1818 |
| Astragalus gambelianus E. Sheld., 1894 |
| Astragalus gentryi Standl., 1940 |
| Astragalus giganteus S. Watson, 1882 |