P. dysenterica: stems erect, 1-2 feet high, loosely branched, downy or woolly; leaves oblong, waved, clasping the stem with rounded auricles, woolly; flower-heads pedunculate, axillary or terminal, corymbose, with a ray of very numerous, linear, spreading bright yellow florets. - Wet pastures, ditches, and roadsides. Fl. August.
P. vulgaris resembles this, but has narrower, less woolly leaves, and the flower-heads are much smaller, the florets of the ray being very short; the minute outer scales of the pappus are also distinct, not forming a little cup as in P. dysenterica.