| Family | Scientific Name | Common Name | Habitat | Distribution | Image |
|---|
| Asteraceae | Centaurea ×gerstlaueri | Meadow Knapweed | Roadsides, disturbed areas. | Native of Europe. Poindexter, Weakley, & Denslow (2011) report its naturalization in Alleghany Co. NC. | |
| Asteraceae | Centaurea ×varnensis | | Disturbed areas, along railroads and in cemeteries. | | |
| Asteraceae | Centaurea aspera | Rough Star-Thistle | Port waif from the 19th century. | Native of Europe. | |
| Asteraceae | Centaurea benedicta | Blessed-thistle | Fields, roadsides, disturbed areas. | Native of Mediterranean Europe and w. and c. Asia. | 
|
| Asteraceae | Centaurea calcitrapa | Purple Star-thistle, Caltrops | Roadsides, disturbed areas. | Native of Europe. | 
|
| Asteraceae | Centaurea cineraria | Dusty Miller, Silver Knapweed, Velvet Centaurea | Probably only a waif. | Native of Mediterranean Europe. | |
| Asteraceae | Centaurea diffusa | Tumble Knapweed, White-flowered Knapweed | Roadsides, disturbed areas. | Native of Europe. | |
| Asteraceae | Centaurea diluta | North African Knapweed | Disturbed areas, probably only a waif in our region. | Native of sw. Europe and n. Africa. | |
| Asteraceae | Centaurea jacea | Brown Knapweed | Roadsides, disturbed areas. | Native of Europe. This species is increasing rapidly in the VA Ridge and Valley. Reported for Alleghany County, NC (Poindexter, Weakley, & Denslow 2011). | 
|
| Asteraceae | Centaurea macrocephala | | Waif on ore piles. | Native of w. Asia. | 
|
| Asteraceae | Centaurea melitensis | Maltese Star-thistle, Tocalote | Roadsides, disturbed areas, eastwards as a ballast and mill waif (waste areas near wool-combing mills, ballast near old seaports). | Native of Mediterranean Europe and Africa. | 
|
| Asteraceae | Centaurea nigra | Black Knapweed, Spanish-buttons | Roadsides, disturbed areas. | Native of Europe. | 
|
| Asteraceae | Centaurea nigrescens | Tyrol Knapweed, Short-fringed Knapweed | Roadsides, disturbed areas. | Native of Europe. This species is increasing rapidly in the n. VA Piedmont. Poindexter, Weakley, & Denslow (2011) report the naturalization of C. nigrescens in Alleghany Co. NC. | 
|
| Asteraceae | Centaurea phrygia | Wig Knapweed | Disturbed areas, persistent or spread from seed mixes. | Native of Europe. Reported for GA Piedmont in Zomlefer et al. (2018). Reported for VA in FNA. | 
|
| Asteraceae | Centaurea scabiosa | Greater Knapweed, Hardheads | Disturbed areas. | Native of Eurasia. Naturalized in KY, PA, NJ (FNA), and other states in e. North America. | |
| Asteraceae | Centaurea solstitialis | Barnaby's-thistle, Yellow Star-thistle | Roadsides, disturbed areas. | Native of Mediterranean Europe. First reported for SC by Hill & Horn (1997). | 
|
| Asteraceae | Centaurea stoebe ssp. micranthos | Spotted Knapweed, Bushy Knapweed | Roadsides, disturbed areas. | Native of Europe. | 
|