| Scirpus carolinianus Lam., 1791 |
| Scirpus castaneus Michx., 1803 |
| Scirpus cephalotes L., 1762 |
| Scirpus cernuus Vahl, 1805 |
| Scirpus cernuus subsp. californicus (Torr.) Thorne, 1978 |
| Scirpus cernuus var. californicus (Torr.) Beetle, 1944 |
| Scirpus chilensis Nees, 1843 |
| Scirpus chirigota C. Wright, 1871 |
| Scirpus coahuilensis Svenson, 1944 |
| Scirpus coloradoensis Britton, 1904 |
| Scirpus complanatus Retz., 1789 |
| Scirpus corymbosus L., 1756 |
| Scirpus cubensis Poepp. & Kunth, 1837 |
| Scirpus cubensis var. gracilis (Boeckeler) Beetle, 1944 |
| Scirpus cyperinus (L.) Kunth, 1837 |
| Scirpus cyperoides Hemsl., 1885 |
| Scirpus debilis Lam., 1791 |
| Scirpus dichotomus L., 1753 |
| Scirpus dictyospermus C. Wright, 1871 |
| Scirpus diphyllus Retz., 1789 |