| Ulmaceae | |
Ulmus americana var. alata
| (Michx.) Spach | | |
| Ulmaceae | |
Ulmus americana fo. alba
| (Aiton) Fernald | Rhodora 47(556): 133 | 1945 |
| Ulmaceae | |
Ulmus americana var. alba
| Aiton | Hort. Kew. 1: 320 | 1789 |
| Ulmaceae | |
Ulmus americana fo. americana
| | | |
| Ulmaceae | |
Ulmus americana fo. ascendens
| A.D. Slavin | Amer. Midl. Naturalist 12: 225 | 1931 |
| Ulmaceae | |
Ulmus americana var. aspera
| Chapm. | Fl. South. U.S. 416–417 | 1860 |
| Ulmaceae | |
Ulmus americana fo. columnaris
| Rehder | J. Arnold Arbor. 3: 42 | 1922 |
| Ulmaceae | |
Ulmus americana var. floridana
| (Chapm.) Little | Phytologia 4(5): 306 | 1953 |
| Ulmaceae | * |
Ulmus americana var. glabra
| Walp. | Ann. Bot. Syst. 3: 424 | 1852 |
| Ulmaceae | |
Ulmus americana fo. intercedens
| Fernald | Rhodora 47(556): 133 | 1945 |
| Ulmaceae | |
Ulmus americana fo. laevior
| Fernald | Rhodora 47(556): 133 | 1945 |
| Ulmaceae | |
Ulmus americana fo. pendula
| (Aiton) Fernald | Rhodora 47(556): 133 | 1945 |
| Ulmaceae | |
Ulmus americana var. pendula
| Aiton | Hort. Kew. 1: 320 | 1789 |
| Ulmaceae | |
Ulmus americana var. rubra
| (Muhl.) Aiton | Hort. Kew. 1: 319 | 1789 |
| Ulmaceae | * |
Ulmus americana var. scabra
| Spach | Ann. Sci. Nat., Bot., sér. 2, 15: 364 | 1841 |
| Ulmaceae | |
Ulmus americana fo. viridis
| F. Seym. | Amer. Midl. Naturalist 48: 249 | 1952 |