During the rosette stage leaves vary from somewhat ovoid in young plants to large and oblong leaves that are quite hairy in older rosettes. During the rosette stage teasel develops a large tap root. Cut-leaved teasel blooms from July through September, and common teasel blooms from June through October. Stems also are prickly. Teasel's unique inflorescence makes the plant readily identifiable when blooming.
Flowers are small and packed into dense oval-shaped heads.
Cut-leaved teasel usually has white flowers, while common teasel usually has purple flowers. Upper stem leaves of common teasel have smooth margins. Cut-leaved and common teasel should be accurately identified before attempting any control measures. It was introduced to North America possibly as early as the 1700's. Common teasel was introduced for use in raising the nap of cloth.