Cirsium carolinianum (Walt.) Fern. & Schubert

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.

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.

Carduus carolinianus Walter, Fl. Carol., 195. 1788; Cirsium flaccidum (Small) Petrak

Cirsium carolinianum is a North American species of plants in the tribe Cardueae within the family Asteraceae. Common name is Carolina thistle or purple thistle or soft thistle or smallhead thistle. The species is native to the central and southern United States, from eastern Texas east to Virginia and the Carolinas, north to the Ohio Valley.

Cirsium carolinianum is a biennial herb up to 180 cm (6 feet) tall, with a relatively short taproot. Leaves have small, thin spines along the edge, much smaller than those of related species. There are usually several flower heads, with pinkish-purple (rarely white) disc florets but no ray florets. Flowers bloom April to July. Its habitats include wooded areas, fields, and roadsides.

Cirsium carolinianum là một loài thực vật có hoa trong họ Cúc. Loài này được (Walter) Fernald & B.G.Schub. mô tả khoa học đầu tiên năm 1948.