Comprehensive DescriptionRead full entry
DescriptionThis annual native plant is 1-2½' tall, branching occasionally. The stems are light green and somewhat ridged. The lower stems often sprawl along the ground in open areas, otherwise this plant is erect. The compound leaves alternate along the stems. They are evenly pinnate, usually with 3 pairs of leaflets, and have long leaf stems (primary petioles). The obovate leaflets are individually 1½" long and 1" across. They are devoid of hairs and pale green on their undersides. There is an extra-floral nectary close to the lowest pair of leaflets on the upper side of each compound leaf. This nectary resembles a small brown spike. The foliage has a slightly rank odor. One or two flowers develop from the upper axils of the compound leaves. These flowers have pedicels about 1" long and tend to nod slightly downward. They are about 1" across, and consist of 5 rounded yellow petals and 10 stamens; the petals are often slightly unequal in size. The flowers are subtended by a light green calyx that is divided into 5 folded sepals; these sepals are shorter than the petals and hairless. In Illinois, the blooming period occurs from late summer through the fall, and lasts about 1-2 months. There is no floral scent. A long seedpod develops from each flower that is 4-6" long, but only 1/3" across. This seedpod curves downward and resembles a sickle in its overall shape. The root system consists of taproot. This plant spreads by reseeding itself.