| Sporobolus virginicus var. pallidus Benth., 1878 |
| Sporobolus viscidus Sohns, 1956 |
| Sporobolus wolfii Vasey, 1883 |
| Sporobolus wrightii Munro ex Scribn., 1882 |
| Spreta Hitchc. & Chase, 1910 |
| Stapfochloa H. Scholz, 2004 |
| Stapfochloa canterae (Arechav.) P.M. Peterson, 2015 |
| Stapfochloa ciliata (Sw.) P.M. Peterson, 2015 |
| Stegosia Lour., 1790 |
| Stegosia cochinchinensis Lour., 1790 |
| Stegosia exaltata (L. f.) Nash, 1909 |
| Steinchisma Raf., 1830 |
| Steinchisma cupreum (Hitchc. & Chase) W.V. Br., 1977 |
| Steinchisma exiguiflorum (Griseb.) W.V. Br., 1977 |
| Steinchisma hians (Elliott) Nash, 1903 |
| Steinchisma laxum (Sw.) Zuloaga, 2003 |
| Stenochloa Nutt., 1848 |
| Stenochloa californica Nutt., 1848 |
| Stenofestuca (Honda) Nakai, 1950 |
| Stenostachys Turcz., 1862 |