Linnaeus, Sp. Pl. 2: 821. 1753.
Welted or curled thistle, chardon crépu
Annuals or biennials
, 30—150 cm.
openly branching, villous with curled, septate hairs to nearly glabrous, spiny wings to 1.5 cm wide, wing spines to 3 mm.
: basal tapering to winged petioles, blades 10—20 cm, margins spiny-toothed to ± shallowly pinnately lobed; cauline sessile, gradually smaller, margins often more deeply divided, marginal spines to 3 mm; abaxial leaf faces ± tomentose with long, one-celled hairs and/or long, curled, septate hairs along veins or glabrate; adaxial faces sparsely hairy or glabrate.
borne singly or in groups of 2—5, 15—18 mm.
spiny-winged to near apex or throughout, to 4 cm.
± spheric, 12—17 × 12—17 mm.
narrowly lanceolate, outer and middle with appressed bases ca. 1 mm wide and appressed to spreading appendages 0.5—1 mm wide, spine tips 1—1.5 mm, inner with unarmed, straight tips.
purple or ± white, 11—16 mm, lobes ca. 3.5 times length of throat.
light brown to gray-brown, 2.5—3.8 mm;
bristles 11—13 mm.
= 16 (Sweden).
Flowering summer—fall (Jul—Sep). Weed of waste ground, pastures, roadsides, fields; 0—500 m; introduced; B.C., N.B., N.S., Ont., Que.; N.J., Pa.; Eurasia.
Canadian distributions above follow R. J. Moore and C. Frankton (1974); I have not seen those specimens.
has been reported also from Arkansas, Connecticut, Iowa, Illinois, Maine, Maryland, Massachusetts, Missouri, New York, North Dakota, Ohio, Rhode Island, Vermont, Virginia, and West Virginia; I have not seen specimens from those states.
Two subspecies of
have been recognized (S. M. A. Kazmi 1964); those are not differentiated here.
closely resembles the much more common
. Some published records of
. Although the degree of spininess and tough versus brittle stems were used as key characters (A. Cronquist 1980; H. A. Gleason and A. Cronquist 1991) to differentiate the two taxa, both characters are subjective, and the second is impractical with dry material.