Family: Asteraceae
bull thistle, common thistle
[Carduus lanceolatus L., more...]
Steve C. Garske
John M. Schoeneker
University of Wisconsin - Madison (WIS-VP)
Etymology: vulgare = Latin for common
Plants: erect, biennial, 2'-6' tall forb; stems very spiny-winged
Leaves: very spiny, pinnately-divided into lobed, then toothed segments
Flowers: head 1 1/2" wide with purple disk flowers, bracts (phyllaries) with spiny tips; inflorescence of several heads in open clusters; blooms June-Oct.
Fruits: dry seed on fluffy, feathery-divided pappus
Habitat: disturbed sites, prairies, marshes, roadsides
Invasiveness: Invasive - Eradicate!
Conservation Status: Introduced - naturalized; ecologically invasive
Plants: erect, biennial, 2'-6' tall forb; stems very spiny-winged
Leaves: very spiny, pinnately-divided into lobed, then toothed segments
Flowers: head 1 1/2" wide with purple disk flowers, bracts (phyllaries) with spiny tips; inflorescence of several heads in open clusters; blooms June-Oct.
Fruits: dry seed on fluffy, feathery-divided pappus
Habitat: disturbed sites, prairies, marshes, roadsides
Invasiveness: Invasive - Eradicate!
Conservation Status: Introduced - naturalized; ecologically invasive
Very spiny robust biennials 1-2 m tall, with taproots . Leaves oblong-lanceolate to obovate, white-arachnoid to subglabrous and green beneath, scabrous-hispid, and appressed-spinulose above, undulate-pinnatifid, the lobes and tip acuminate with firm, strawcolored spines, the bases decurrent into conspicuous spiny wings. Corollas deep rose-purple; involucre 2.5-3.5 {-4) cm high, the herbaceous bracts widely divergent from near or below the middle, all long-attenuate into a stout spine. Achenes 3-4 mm long, yellowbrown, finely striped with black.
Johnson, M.E. and H.H. Iltis. 1963. Preliminary reports on the flora of Wisconsin: No. 48. Compositae Family. Wisconsin Academy of Sciences, Arts & Letters. 52:255-342.
An abundant aggressive weed throughout Wisconsin, on roadsides, grazed pastures, and disturbed open or wooded areas, becoming less abundant in wet to mesic prairies, marshes, bogs or swampy woods. Flowering from mid-July to early October; fruiting from late July to mid-October.
Johnson, M.E. and H.H. Iltis. 1963. Preliminary reports on the flora of Wisconsin: No. 48. Compositae Family. Wisconsin Academy of Sciences, Arts & Letters. 52:255-342.
Other Treatments:
Additional Resources:
Additional Resources:
John M. Schoeneker
Christopher Noll
Kenneth J. Sytsma
Robert Bierman
Christopher Noll
Robert W. Freckmann
Botanical Illustration
Botanical Illustration
