Biennials, 50-180 cm; taproots short with many slender, fibrous lateral roots. Stems usually single, erect, glabrous to ± tomentose, sometimes sparsely villous with septate trichomes; branches few, usually distal, ascending. Leaves: blades linear to oblanceolate or elliptic, 10-30 × 1-5 cm, unlobed and spinulose to irregularly dentate or pinnatifid, lobes narrowly to broadly triangular, sometimes coarsely toothed or lobed toward base, acuminate, main spines slender, 1-5 mm, abaxial faces gray-tomentose, adaxial glabrous or sparsely villous with septate trichomes; basal often present at flowering, petioles slender, winged, bases long-tapered; principal cauline relatively few (10-25), petiolate or distal sessile, mostly restricted to proximal 1/2 of stems, progressively reduced distally, bases tapered, not decurrent; distal cauline widely separated, linear to narrowly elliptic, reduced, becoming ± bractlike, merely spinulose to irregularly dentate or shallowly lobed. Heads (1-)2-9(-many), in paniculiform arrays. Peduncles slender, 1-15 cm (not overtopped by distal leaves. . Involucres narrowly ovoid to campanulate, 1.2-2 × 1.2-2 cm, thinly arachnoid-ciliate. Phyllaries in 7-10 series, imbricate, green, linear to lanceolate (outer) or linear to linear-lanceolate (inner), abaxial faces with narrow, glutinous ridge; outer and middle ascending to appressed, bodies entire, apices widely spreading (at least the outer), spines ascending to spreading (at least the outer), slender, 1-4 mm; apices of inner phyllaries flat, often twisted, acuminate. Corollas pink-purple (white), 15-20 mm, tubes 5-9 mm, throats 5-7 mm (noticeably wider than tubes. , lobes 4-5 mm; style tips 4 mm. Cypselae light brown, 3-4 mm, apical collars yellowish, 0.5-1 mm; pappi 12-14 mm. 2n = 20, 22. Flowering spring-summer (Apr-Jul). Wooded areas, openings, fields, roadsides; 50-300 m; Ala., Ark., Ga., Ill., Ind., Ky., La., Miss., Mo., N.C., Ohio, Okla., S.C., Tenn., Tex. Cirsium carolinianum is widely distributed in the southeastern United States: on the Gulf coastal plain from Texas to Alabama north through the Ouachita and Ozark highlands to southeastern Missouri; in the Ohio River Valley from southernmost Illinois to southern Ohio and northern Kentucky; and in the southern Appalachians and Piedmont from Alabama and Tennessee to southern Virginia. Cirsium carolinianum, though widespread, is a taxon of conservation concern over part of its range. The replacement of open woods by dense forests brought about by fire suppression has greatly reduced available habitat.
From Flora of Indiana (1940) by Charles C. Deam
I have found this species [C. virginianum sensu Deam] only on wooded slopes. It is rare, and Phinney's report for it from the area of Delaware, Jay, Randolph, and Wayne Counties I refer to some other species. This is a southern plant, and Phinney did not report all of the species that are common in his area.
Slender, fibrous-rooted biennial 5-15(-18) dm; stem glabrous or arachnoid, sometimes more evidently tomentose when young; lvs closely white-tomentose beneath, glabrous or hirsute on the upper surface, from merely spinose-ciliate and up to ca 2.5 cm wide to evidently pinnatifid and to 5 cm wide, the basal ones to 3 dm, the cauline relatively few, mostly 10-25, 8-15 cm and (except when lobed) seldom more than 1.5 cm wide, narrow-based, reduced upward; heads (1-) several, on long, naked peduncles terminating the branches; invol 1.5-2 cm, its middle and outer bracts with a glutinous dorsal ridge and a slender, suberect or spreading spine 1.5-4 mm, the
inner merely attenuate and commonly crisped; fls pink-purple; achenes 3-4 mm; 2n=20. Open woods and dry, sandy soil; s. O. to the mts. of N.C., Ga., and Ala., w. to Mo. and Tex. May, June. (C. flaccidum)
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.