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DescriptionThis perennial wildflower is a vine about 1½-4' long that branches occasionally. This vine climbs adjacent vegetation for support using its tendrils. The stems are light green, yellowish green or reddish green, glabrous or nearly so, and either winged, angular, or grooved. Alternate compound leaves occur at intervals along these stems; they are even-pinnate with 2-4 pairs of leaflets (usually there are 3 pairs of leaflets). At the end of each compound leaf, there is a branched tendril. The leaflets are ¾-2" long and 1/6-3/4" (4-20 mm.) wide; they are narrowly elliptic to lanceolate-elliptic in shape and smooth along their margins. The upper blade surface is medium green, while the lower surface is pale green. All parts of the compound leaf are glabrous or nearly so. The petioles and rachises of the compound leaves are light green, yellowish green, or reddish green; they are glabrous or nearly so. At the base of each petiole, there is a pair of stipules about ¼-1" long. Each stipule is half-sagittate or half-hastate in shape; it has a basal lobe that tapers to a point, a tip that tapers to a point, and an outer margin that is usually smooth. Sometimes the foliage of this wildflower is sparsely and minutely pubescent (puberulent). Individual racemes of 2-8 flowers develop from the axils of compound leaves; the peduncles of these racemes are about as long as, or a little shorter than, the length of the compound leaves. Each flower is about ½-¾" long, consisting of 5 petals with a pea-like floral structure, a tubular calyx with 5 teeth, several stamens, and a pistil with a single style. The petals consist of an upright banner and a pair of projecting wings that enclose the keel. These petals can be pink, bluish purple, or white; sometimes they are bicolored with a veiny pink banner and white wings. The calyx is pale green or yellowish green and glabrous. The blooming period occurs from late spring to mid-summer, lasting about 1 month. Afterwards, the flowers are replaced by elongated seedpods about 1-2½" long, ¼" across, and flattened. Each seedpod splits open into two valves to release its seeds. The small seeds are globoid in shape and somewhat flattened. The root system is fibrous and rhizomatous. At favorable sites, vegetative colonies of plants often develop from the rhizomes.