Missouri Eveningprimrose (Oenothera macrocarpa var. macrocarpa )
Missouri Eveningprimrose Oenothera macrocarpa Nutt. var. macrocarpa
Missouri eveningprimrose is a decumbent to ascending perennial 6-18 in. tall with silvery-canescent stems. The alternate leaves are linear-oblanceolate, leathery in texture, and finely silvery-pubescent. The flowers are axillary, with 4 sepals united to form a long tube (hypanthium) and 4 large, free, yellow petals. The stigma is large and 4-lobed. The fruit is an orbicular capsule 1.5-3 in. long and 1.5-2 in. wide with 4 broad wings. This plant is usually associated with disturbed areas in the prairie. The flowers close during the daytime, opening toward evening.