Arctium

Biennial herbs, with glandular and simple hairs; taproot stout. Leaves basal and cauline, alternate, entire or serrulate, petiolate. Capitula more or less globose to ovoid, in terminal corymbose or racemose clusters or solitary; involucral bracts in many series, narrow, hooked at apex, unequal, outer ones spreading or reflexed in fruit, herbaceous, glabrous or cobwebbed; receptacle flat with numerous rigid subulate scales. Florets bisexual, tubular, more or less equal, purple or white; corolla deeply 5-lobed, glabrous; anthers sagittate at base, acuminate at apex; style bilobed, with linear terete branches, apices truncate and papillose. Cypselas obovoid-oblong, somewhat compressed, ribbed, glabrous; pappus of several unequal series of free bristles, barbellate, deciduous, golden-yellow.