Young leaves are also egg-shaped, except at the truncated base. The undersides of these leaves are loosely hairy and light green. Stem leaves are much smaller, alternate, and egg-shaped. Flowers dry to a bur, and the hooked bracts are often confused with a thistle. Produced during the second year of growth.
Stems are erect, branched, hollow, hairy, and ridged.
Stems may reach 5 ft in height. After senescence, the remaining burs on the stems of common burdock may resemble a thistle. However, the dried flowers of thistle plants do not have hooked bracts like common burdock.