| Schoenus polyphyllus Vahl, 1798 |
| Schoenus rugosus Vahl, 1798 |
| Schoenus secans L., 1759 |
| Schoenus setaceus Bergius, 1772 |
| Schoenus spadiceus Kunth, 1815 |
| Schoenus tenuifolius Kunth, 1815 |
| Scirpeae T. Lestib. ex Dumort., 1827 |
| Scirpidium Nees, 1834 |
| Scirpidium aciculare (L.) Nees, 1834 |
| Scirpidium nigrescens Nees, 1842 |
| Scirpidium sulcatum (Roth) Nees, 1842 |
| Scirpoides Scheuchz. ex Seguier, 1754 |
| Scirpoides mexicana (C.B. Clarke ex Britton) Goetgh. ex C.S. Reid & J.R. Carter, 2017 |
| Scirpus L., 1753 |
| Scirpus acicularis L., 1753 |
| Scirpus acutangulus Roxb., 1820 |
| Scirpus acutus Muhl. ex Bigelow, 1814 |
| Scirpus acutus f. congestus (Farw.) Fernald, 1921 |
| Scirpus acutus var. malheurensis (L.F. Hend.) Beetle, 1948 |
| Scirpus acutus var. occidentalis (S. Watson) Beetle, 1948 |