| Heterosteca americana (L.) Desv., 1813 |
| Heterosteca juncifolia Desv., 1810 |
| Hexarrhena J. Presl, 1830 |
| Hexarrhena cenchroides J. Presl, 1830 |
| Hierochloe R. Br., 1810 |
| Hierochloe mexicana (Rupr. ex E. Fourn.) Benth. ex Hitchc., 1930 |
| Hilaria Kunth, 1815 |
| Hilaria annua Reeder & C. Reeder, 1988 |
| Hilaria belangeri (Steud.) Nash, 1912 |
| Hilaria belangeri var. belangeri (Steud.) Nash, 1912 |
| Hilaria belangeri var. longifolia (Vasey) Hitchc., 1935 |
| Hilaria cenchroides Kunth, 1815 |
| Hilaria cenchroides var. ciliata Scribn., 1891 |
| Hilaria cenchroides var. texana Vasey, 1890 |
| Hilaria ciliata (Scribn.) Nash, 1912 |
| Hilaria ciliata (Scribn.) Sohns, 1956 |
| Hilaria hintonii Sohns, 1956 |
| Hilaria mutica (Buckley) Benth., 1881 |
| Hilaria rigida (Thurb.) Benth. ex Scribn., 1882 |
| Hilaria semplei Sohns, 1956 |