| Name | Ustilago segetum f. polygoni P. Karsten |
| Authorship | P. Karsten |
| Rank | Forma |
| Placed in | Ustilago segetum (Bulliard) Roussel |
| Citation | 1866 Fungi Fenniae Exsicc. 4: 394 |
| Holdings | 1 Specimen held in the Harvard University Herbaria identified as Ustilago segetum f. polygoni P. Karsten |
| Identification made in | [no date] (1) |