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DescriptionThis vine is a summer annual about 2-8' long that twines about adjacent vegetation and branches occasionally. The slender stems are light green to reddish green, terete, and covered with either appressed white hairs (var. bracteata) or spreading tawny hairs (var. comosa). Alternate trifoliate leaves occur along these stems. The terminal leaflets are up to 2½" long (var. bracteata) or as much as 4" long (var. comosa); the lateral leaflets are a little shorter. All leaflets are ovate to ovate-rhombic in shape and smooth along their margins. The upper surface of the leaflets is medium green and hairless to sparsely covered with appressed hairs; the lower surface of the leaflets is pale green and usually more hairy. In each trifoliate leaf, the petiolule (basal stalklet) of the terminal leaflet is up to ¾" long, while the petiolules of the lateral leaflets are about 1/8" long. The slender petioles are 2-6" long. At the base of each petiole, there is a pair of small stipules less than ¼" long. Occasionally, congested racemes of 2-15 flowers up to 2" long are produced from the axils of the leaves. Individual flowers consist of 5 petals, a tubular calyx with 4 teeth, several stamens, and a pistil. The petals have a pea-like floral structure consisting of an upright banner, 2 lateral wings, and a keel that is curved upward. The edges of the banner are often folded backward, while the narrow wings and keel project forward. The petals are light pink, pale lavender, or white; the calyx is light green to nearly white and either hairless or hairy. The blooming period occurs from mid-summer into the fall and lasts about 1½-3 months. Fertile flowers are replaced by seedpods about 1-1½" long; these seedpods are oblongoid and flattened with short curved beaks. Each seedpod contains 1-4 relatively large seeds; individual seeds are reniform and flattened. In addition to the preceding flowers and their seedpods, Hog Peanut also produces self-fertile flowers that lack petals. These inconspicuous flowers are produced on low stolons along the ground; they mature into single-seeded fleshy fruits with an obovoid shape. Sometimes, these fruits become subterranean.