Cirsium altissimum
| Tall thistle |
Cirsium arvense
| Field thistle; Canadian thistle |
Cirsium carolinianum
| Carolina thistle |
Cirsium discolor
| Pasture thistle; Field thistle |
Cirsium hillii
| Hill's thistle |
Cirsium muticum
| Fen thistle; Swamp thistle |
Cirsium pitcheri
| Dune thistle |
Cirsium pumilum
| Pasture thistle |
Cirsium pumilum var. hillii
| Hill's thistle |
Cirsium undulatum
| Wavy-leaved thistle |
Cirsium vulgare
| Bull thistle |