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Common burdock

(Arctium minus)

Common burdock is a biennial forb that is native to Europe. The first year of growth is a basal rosette, producing large cordate, thickly hairy leaves. The second year of growth produces a coarse, multi-branched, erect stem that will grow to heights of 3 to 10 feet tall. The large, dark green leaves are alternate and appear to have toothed or wavy margins. They are broadest and the base of the leaf and diminish as they approach the tip of the leaf, and have a hairy underside. The flowers appear at the end of the branches, numerous, clustered, and are pink to purple in color. At the base of the flower, there are many spines that often have a hook on the end. The flower and the spines dry and becomes an easily dispersible bur. Flowering and seed production occurs from July to October. The plant grows from a sturdy taproot that is brown and fleshy in color.

Common burdock fact sheet