is a non-native species, originating in Europe, Asia and North Africa. Plants are usually hairless, producing upright stems that branch all along. Basal and lower stem leaves are pinnately lobed or fully divided, with one large terminal lobe and (usually) 2 to 6 pairs of lateral lobes, all of which have irregularly toothed, or lobed edges. Leaves grow on stalks up to 1.5 inches long. Upper stem leaves are progressively smaller and less lobed.
The inflorescence is a compact, spherical cluster of several dozen flowers at the top of the stem. Flowers are small; the four oblong yellow petals are only about 0.15 inches long, while the four green sepals are even shorter. Petals are abruptly narrower at the base.
The cylindrical green fruits are relatively long (up to 2 inches) and very narrow, and angled upwards, often surrounding the flower cluster. Fruits are slightly curved or completely straight.