Perennial by creeping roots (sometimes annual?), ascending to erect, 1-6 dm; lvs linear to lanceolate or oblanceolate, 3-8 cm, gradually tapering to a petiolar base, entire to runcinate-pinnatifid, the basal half commonly more coarsely toothed than the upper; fls few, sessile in the upper axils, erect, buds nodding, long-acuminate; hypanthium slender, 1-2 cm, strigose; sep lance-linear, reflexed at anthesis, 1.5-2.5 cm, usually long connivent; pet obcordate, white or pink, 2-4 cm; stamens alternately unequal; fr narrowly obovoid or clavate, 10-18 mm, 4-sided, roundly 8-ribbed and deeply sulcate, tapering to both ends, sterile below; 2n=14. Dry, open places; Mo. and Kans. to Tex., and intr. eastward. May, June. (Hartmannia s.)

Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.

©The New York Botanical Garden. All rights reserved. Used by permission.

Kearney and Peebles 1969, McDougall 1973, Wagner et. all 2007

Duration: Perennial Nativity: Native Lifeform: Subshrub General: Herbaceous to suffrutescent perennials, stems several, slender, branching or occasionally simple, herbage pubescent, plants with creeping rhizomes. Leaves: Alternate, cauline or in a basal rosette, blades elliptic to elliptic-oblanceolate or ovate, sometimes lanceolate, cauline leaves 1-7 cm long, margins subserrate to weakly sinuate-dentate or occasionally sinuate-pinnatifid, short-petioled to subsessile. Flowers: White to rose-colored, petals obcordate, 2.5-4 cm long, sepals 1-2 cm long, the long-acuminate lobes united but free at the tips, calyx, stamens, borne few to several in upper leaf axils, nodding in bud on reflexed stems, buds rounded in cross-section with free tips to 4 mm long, flowers opening in the evening. Fruits: Capsules club-shaped, strongly 8-ribbed, the main body 3-5 mm thick and attenuate to a slender base, the upper face of each valve with a prominent rib. Seeds obovoid to fusiform, clustered in 2 or more rows in each cell. Ecology: Found from 3,000-3,500 ft (914-1067 m); flowering May-June. Distribution: Missouri and Kansas to Texas, Arizona, and Mexico. Notes: Look to the nodding buds and the white to pink flower petals 2.5-4 cm long to help identify this species. Ethnobotany: There is no use recorded for this species, but other species in this genus have uses. Etymology: Oenothera is from Greek oinos, wine and thera, to imbibe, while speciosa means showy. Synonyms: None Editor: LCrumbacher 2012

From Flora of Indiana (1940) by Charles C. Deam

I have collected this species from the side of a railroad, a roadside to which it had escaped from a cemetery, and a roadside where it was common, and also in an adjoining alfalfa field. I planted some of it and when, in two years, it had spread by underground rootstocks over a large area, it became necessary to destroy it and the process required three years of careful work. Since I never permitted it to seed I do not know its ability to propagate from seed but most species of this genus should be regarded with suspicion. This species, no doubt, in time will become an obnoxious weed.

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Indiana Coefficient of Conservatism: C = null, non-native

Wetland Indicator Status: N/A