| Trifolium albopurpureum var. olivaceum (Greene) Isely, 1980 |
| Trifolium amabile Kunth, 1824 |
| Trifolium amabile var. amabile Kunth, 1824 |
| Trifolium amabile var. hemsleyi (Lojac.) D. Heller & Zohary, 1984 |
| Trifolium amabile var. longifoliolum Hemsl., 1879 |
| Trifolium amabile var. mexicanum (Hemsl.) D. Heller, 1984 |
| Trifolium arizonicum Greene, 1895 |
| Trifolium arvense Walter, 1788 |
| Trifolium bejariense Moric., 1833 |
| Trifolium calocephalum Nutt. ex Torr. & A. Gray, 1838 |
| Trifolium calophyllum Greene, 1897 |
| Trifolium carolinianum Michx., 1803 |
| Trifolium carolinianum f. bejariense (Moric.) McDermott, 1910 |
| Trifolium cognatum House, 1906 |
| Trifolium columbinum Greene, 1887 |
| Trifolium columbinum var. olivaceum (Greene) Jeps., 1901 |
| Trifolium cyathiferum Lindl., 1827 |
| Trifolium denudatum Nutt., 1847 |
| Trifolium depauperatum Desv., 1814 |
| Trifolium dianthum Greene, 1897 |