COMMON BURDOCK - Arctium minus (Hill) Bernh

Asteraceae - (Sunflower family)

First year growth is a large circular mound of long, heart shaped, hairy leaves.  The second year is the same with the addition of a tall coarse branched stem growing up to 10 feet tall.  This plant has many purple thistle-like flowers.  After they mature they dry into hard, brown, Velcro-type burs that catch in clothing and animal fur aiding in the efficient transport of the seeds inside.  Burdock is a very aggressive plant that thrives in disturbed and waste areas but spreads quickly to others.

The following is courtesy of Weeds of the West:

Common burdock is a biennial, producing a rosette of large, cordate, thickly hairy leaves the first year and an erect, much branched, coarse stem 3 to 10 feet tall the second year. The leaves are alternate, large, broadest at the leaf base, somewhat diminished upwards, margins toothed or wavy, wooly beneath at least when young, dark green above. Flowers are purple, heads borne in leaf axils or at the end of branches, numerous, clustered, covered with many slender, hooked spines, achenes gray to brown, mottled, oblong, about 1/4 inch long, flattened and slightly curved.

Native of Europe, common burdock is now established throughout much of the U.S.  It is commonly found growing along roadsides, ditchbanks, in pastures and waste areas. The burs can become entangled in the hair of livestock allowing seed to be distributed to new areas. Flowering and seed production occur from July to September.
(Courtesy of Weeds of the West)

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