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DescriptionThis introduced annual plant is up to 1' tall, branching frequently and having a bushy appearance. The stems are green or reddish green and pubescent; they have a tendency to sprawl. The alternate leaves are trifoliate; they have long petioles that are hairless. The leaflets are ovate or obovate, hairless, and slightly dentate along the margins. They have conspicuous pinnate veins that are straight, but lack any white chevrons. The petiole of the middle leaflet is conspicuously longer than the petioles of the lateral leaflets; the petioles of the latter are often sessile, or nearly so. Each leaflet is about ¾" long and half as much across. From the axils of the upper trifoliate leaves, their develops individual flowerheads from pubescent stalks about 1" in length. Each of these stalks is longer than the petiole of the adjacent trifoliate leaf. The yellow flowerheads are up to ½" across. They are more or less spherical and consist of about 15-40 flowers. Each flower is about 1/6" long. It has 5 elongated yellow petals and a light green calyx that is shorter than the petals and inconspicuous. The upper petal, or standard, has an outer surface that is conspicuously grooved; it is parallel to the keel (the lower petals) and functions like a protective hood. The blooming period occurs during the summer and lasts about 1-2 months. The petals of the flowers are persistent, turning light brown or nearly white on the flowerheads. Each flower produces a single seedpod that is shorter than the persistent keel. The root system consists of a taproot, which can form nodules on secondary roots to accommodate nitrogen-fixing bacteria. This plant spreads by reseeding itself, and often forms colonies.