Native. Annual and winter annual. Propagates by seeds. Time of bloom: June to October. Seed-time: July to November. Range: Nova Scotia to the Northwest Territory, southward to Georgia, Alabama, Louisiana, and Arkansas. Habitat: Fields, meadows, roadsides, and waste places.
In rich, moist soil this weed sometimes attains a height of ten feet, but is more often three to six feet tall Stem slender, smooth, often glaucous, sometimes of a purplish tinge but most commonly deep green. Lower and basal leaves lance-shaped in outline but deeply and irregularly lobed, the terminal segment large and acutely pointed, the lateral ones unequal in number and size, not opposite, and frequently with points turned backward, narrowing to margined petioles; upper leaves much smaller, often entire and sessile. Heads numerous, in a loosely branching terminal panicle and in short axillary clusters; heads yellow, hardly more than a quarter-inch broad, the involucre cylindric, its inner row of bracts linear, the outer ones short and spreading. Achenes oblong-oval, tipped with a slender beak; pappus white, very fine and silky. The plant has a strong, unpleasant odor resembling opium, and, though cattle and sheep eat it readily, it will damage dairy products if milch cows get much of it. (Fig. 376.)
Means of control the same as for Prickly Lettuce.