Cirsium repandum Michx. (redirected from: Carduus repandus)
Family: Asteraceae
[Carduus repandus (Michx.) Pers.]
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Perennials, 20-80 cm; creeping roots deep-seated, sometimes appearing as taprooted biennials. Stems 1-several, spreading to erect, (usually very leafy in distal 1/2), loosely arachnoid, and villous with jointed, multicellular trichomes; branches 0-few from above middle, ascending. Leaves linear to oblong or oblanceolate, 6-16 × 1-3.5 cm, unlobed to sinuate-dentate or shallowly pinnatifid, main spines 1-4 mm, fine, faces ± green, shaggy-villous with septate trichomes, abaxial loosely arachnoid when young; basal and proximal cauline usually absent at time of flowering; mid and distal nearly uniform in size or gradually reduced, bases clasping; distalmost cauline ± bractlike. Heads 1-5, in corymbiform arrays. Peduncles 0-2 cm. Involucres ovoid or cylindric to campanulate, 2-4 × 1.5-4 cm, loosely arachnoid, ± glabrate. Phyllaries in 6-9 series, imbricate, lanceolate (outer) to linear (inner), abaxial faces with glutinous ridge, outer and middle tightly appressed, bodies scabrous or spinulose, spines erect or weakly ascending, 1-4 mm; apices of inner phyllaries long-acuminate, spineless. Corollas light purple, 33-40 mm, tubes 14-15 mm, throats 12-15 mm, lobes 7-9 mm; style tips 4.5-6 mm. Cypselae light brown, 3.5-4 mm, apical collars yellowish, ca. 0.8 mm; pappi 15-30 mm. 2n = 30.

Flowering spring-summer (May-Jul). Sandhills, pine barrens, roadsides; 0-150 m; Ga., N.C., S.C., Va.

Cirsium repandum occurs on the Atlantic coastal plain. R. J. Moore and C. Frankton (1969) suggested that Cirsium repandum originated through ancient hybridization between C. pumilum var. pumilum and C. horridulum. They noted that an artificial hybrid (2n = 32) between C. repandum (2n = 30) and C. horridulum (2n = 34) had a mosaic of features of the parental taxa.

Deep-rooted perennial, 2-6 dm, the herbage loosely and rather copiously arachnoid when young, subglabrate or merely hirsute in age; lvs crowded (internodes commonly less than 1 cm), narrow, sessile, 6-15 נ1-2.5 cm, densely spiny-margined, coarsely toothed or shallowly lobed, and often finely toothed as well; heads (solitary) several, terminating short branches from near the summit, only shortly or scarcely pedunculate, purple; invol 2.5-4 cm, the middle and outer bracts with short, mostly erect spine-tip, the glutinous dorsal ridge poorly developed or wanting; inner bracts looser and merely attenuate; achenes 3.5-4 mm; 2n=30. Dry, sandy soil, especially in sand-hills and pine-barrens; se. Va. to Ga. June-Sept.

Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.

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