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DescriptionThis wildflower is a summer annual about 2-10" tall that branches sparingly to abundantly; its stems are ascending to sprawling. The stems are purple and terete with appressed white hairs that point downward. The alternate compound leaves are trifoliate; their leaflets are ¼-1" long and about one-third to one-half as much across. The leaflets are broadly oblong-elliptic to oblong-obovate in shape and smooth to slightly serrated along their margins; sometimes the margins are slightly ciliate. The upper leaflet surface is medium to dark green, while the lower leaflet surface is pale green; both leaflet surfaces are glabrous or nearly so. Leaflet venation is pinnate; the abundant lateral veins are straight and parallel to each other. Each trifoliate leaf has a short petiole (basal stalk) about 1-3 mm. long, while the leaflets have short petiolules (basal stalklets) about 0.5-1.0 mm. long. At the base of each petiole, there is a pair of stipules about 3-4 mm. long; they are brown, membranous, longitudinally veined, and broadly lanceolate in shape with margins that are smooth and ciliate. From the axils of the leaves, there develops 1-3 flowers on short pedicels about 1-3 mm. long. The orientation of the flowers varies from erect to lateral. Each flower is about ¼" (6 mm.) long, consisting of 5 petals, a short calyx with 5 teeth, and the reproductive organs. The petals are arranged in a pea-like floral structure, consisting of a banner, a curved keel, and a pair of wings. The banner is predominately pink or purple with several dark purple veins near its base, while the smaller wings are white. The keel is predominantly white, except along its outer edge, where it is blackish purple. The calyx is light green with ovate-oblong teeth. At the base of the calyx, there are 2 or more bractlets that are largely hidden by the flower. The blooming period occurs from mid-summer into fall, lasting about 1-2 months. In addition to the insect-pollinated flowers, sometimes inconspicuous flowers are produced that are self-fertile. The flowers are replaced by small seedpods about 4-5 mm. long. These seedpods are broadly ovoid and flattened in shape with a tapered base and short beak. Each mature seedpod contains a single dark seed that is ovoid and somewhat flattened. The 2-valved seedpods eventually split open to release their seeds. The root system consists of a shallow taproot. This wildflower reproduces by reseeding itself.