Annual seed-propagated weed up to 100 cm tall. Prefers moist, nutrient-rich, especially nitrogen-containing sandy to loam soils.
Cotyledons are rounded, slightly petiolate (stalked), with a shallowly emarginated end. The first true leaves are hairless, shiny green, ovate (Picture 1). The next leaves are petiolate, runcinate-pinnatipartite (feathery with lobe pointing downwards and cut reaching past halfway to the midrib), prickly-serrated, and the upper leaves are stem-clasping (Picture 2). The yellow flower heads are borne in loose, terminal cymes (Picture 3). Each plant produces up to 4,700 seeds (100,000 seeds in extreme cases). They are somewhat flattened, leather brown, and 3-ribbed (Picture 4).