| Elymus philadelphicus L., 1755 |
| Elymus philadelphicus var. hirsutus Farw., 1927 |
| Elymus philadelphicus var. pendulus (Eaton & J. Wright) Farw., 1927 |
| Elymus pilosus (J. Presl) Á. Löve, 1984 |
| Elymus ponticus (Podp.) N. Snow, 2007 |
| Elymus pringlei Scribn. & Merr., 1901 |
| Elymus pubiflorus (J.G. Sm.) Burtt Davy, 1902 |
| Elymus repens (L.) Gould, 1947 |
| Elymus repens subsp. caesius (J. Presl & C. Presl) Soó, 1980 |
| Elymus repens subsp. repens (L.) Gould, 1947 |
| Elymus riparius Wiegand, 1918 |
| Elymus robustus Scribn. & J.G. Sm., 1897 |
| Elymus robustus var. vestitus Wiegand, 1918 |
| Elymus simplex Scribn. & Williams, 1898 |
| Elymus simplex var. luxurians Scribn. & T.A. Williams, 1898 |
| Elymus sitanion Schult., 1824 |
| Elymus smithii (Rydb.) Gould, 1947 |
| Elymus spicatus (Pursh) Gould, 1947 |
| Elymus stebbinsii Gould, 1947 |
| Elymus subsecundus (Link) Á. Löve & D. Löve, 1964 |