| Ulmus alata Michx. | • map | • images (1) |
| Ulmus americana L. | • map | • images (1) (2) (3) |
| Ulmus rubra Muhl. | • map | |
| Uniola paniculata L. | • map | • images (1) |
| Urtica chamaedryoides Pursh | • map | |
| Urtica urens L. | • map | |
| Utricularia biflora Lam. | • map | |
| Utricularia cornuta Michx. | • map | • images (1) (2) |
| Utricularia fibrosa Walt. | • map | • images (1) (2) (3) |
| Utricularia floridana Nash | • map | |
| Utricularia gibba L. | • map | |
| Utricularia inflata Walt. | • map | • images (1) |
| Utricularia juncea Vahl | • map | |
| Utricularia olivacea C. Wright ex Griseb. | • map | |
| Utricularia purpurea Walt. | • map | • images (1) (2) |
| Utricularia radiata Small | • map | |
| Utricularia subulata L. | • map | |
| Uvularia floridana Chapman | • map | |
| Uvularia perfoliata L. | • map | • images (1) |
| Uvularia puberula Michx. | • map | |
| Uvularia sessilifolia L. | • map | |
