Arctium tomentosum Mill.
Family: Asteraceae
cotton burdock, hairy burdock, woolly burdock
Arctium tomentosum image
Emmet J. Judziewicz  

Etymology
: tomentosum = (Latin) having a mass of rough hairs

Plants
: erect, biennial, 2'-4' tall forb

Leaves
: alternate, large, heart-shaped base, on stalks getting shorter toward the top, lower stalks mostly hollow

Flowers
: head 1/2"-1" wide with pink to purple disk flowers, densely woolly, bracts(phyllaries) only slightly hooked; inflorescence a cluster of long-stalked heads

Fruits
: round, slightly bristly bur

Conservation Status
: Introduced - locally established
Similar to A. minus, but inflorescences corymbose, the bracts densely cottony-pubescent. 2n=36 (Poddubnaja 1944, ex Darlington 1955).

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.

Native to temperate Europe, Caucasus and Siberia (Hegi), in the United States more common to the south and east. Collected just seven times in Wisconsin. The first three were: Ashland Co. : Weed at Berkshire Mine, Mellen, Sept. 7, 1927 [fr], Fassett 10084 (WIS); Town of Morse, Aug. 31, 1939 [fl], M clntosh c-812 (MIL, WISM). Fond du Lac Co.: Campbellsport, nea:r railroad sta., Aug. 1911 [fr], Ogden 24994 (MIL).

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.