| Betulaceae | |
Alnus rugosa var. americana
| (Regel) Fernald | Rhodora 47: 350 | 1945 |
| Betulaceae | |
Alnus rugosa var. americana
| (Regel) Fernald | Rhodora 47(563): 350 | 1945 |
| Betulaceae | |
Alnus rugosa fo. emersoniana
| Fernald | Rhodora 47: 347 | 1945 |
| Betulaceae | |
Alnus rugosa fo. hypomalaca
| Fernald | Rhodora 47(563): 353–354, pl. 982, f. 1–3 | 1945 |
| Betulaceae | |
Alnus rugosa var. obtusifolia
| (Regel) H. Winkl. | Pflanzenr. IV,61: 120 | 1904 |
| Betulaceae | |
Alnus rugosa var. occidentalis
| (Dippel) C.L. Hitchc. | | |
| Betulaceae | |
Alnus rugosa fo. rugosa
| | | |
| Betulaceae | |
Alnus rugosa var. rugosa
| | | |
| Betulaceae | |
Alnus rugosa var. serrulata
| (Aiton) H. Winkl. | Pflanzenr. IV. 19(Heft 61): 120 | 1904 |
| Betulaceae | |
Alnus rugosa fo. tomophylla
| (Fernald) Fernald | Rhodora 47: 353 | 1945 |
| Betulaceae | |
Alnus rugosa var. tomophylla
| (Fernald) Fernald | Rhodora 47(563): 353 | 1945 |
| Betulaceae | |
Alnus rugosa var. typica
| H.J.P. Winkl. | Pflanzenreich 19(4.61): 119 | 1904 |