| Name | Cirsium clavatum var. americanum (A. Gray) D. J. Keil |
| Authorship | (A. Gray) D. J. Keil |
| Rank | Variety |
| Placed in | Cirsium clavatum (M. E. Jones) Petrak |
| Citation | 2004 Sida 21(1): 211 |
| Holdings | 1 Specimen held in the Harvard University Herbaria identified as Cirsium clavatum var. americanum (A. Gray) D. J. Keil |
| Identification made in | [no date] (1) |