Angiosperms: Dicotyledons

Onagraceae
Evening Primrose Family

• Stem: biennial; 3’ to 6’ tall; branching above; hairy.
• Leaves: alternate; elongate-oval, tapering to both ends; 5” by 1”; sessile; margins weakly toothed; hairy above and below.
• Inflorescence: spikes of flowers crowded at the ends of flower stalks from the stem tip and upper leaf axils.
• Flowers: petals yellow, 7/8” long on floral tubes 1 1/8” long atop a 1/2” ovary (inferior ovary); sepals 5/8” long, hairy, recurved; flowering from mid-July to late August.
• Fruits: elongate capsules, 1” by 3/16” in diameter, weakly angled, hairy, opening by four sections separating at the tip and recurving; fruiting begins in late July.
• Habitat: frequent in disturbed places in mesic to moist soil on roadsides, on prairies, and in open woods.
• Bibliography from Biodiversity Heritage Library
• Vascular Plants of Iowa