This section is from the book "An Illustrated Flora Of The Northern United States, Canada And The British Possessions Vol2", by Nathaniel Lord Britton, Addison Brown. Also available from Amazon: An Illustrated Flora of the Northern United States, Canada and the British Possessions. 3 Volume Set..
Oenothera fruticosa L. Sp. Pl. 346. 1753.
Kneiffia fruticosa Raimann, in Engl. & Prantl, Nat.
Erect, usually branched, 1°-3° high, pubescent with short or long hairs, or nearly glabrous. Leaves lanceolate, ovate-lanceolate or oval-lanceolate, acute or obtusish at the apex, narrowed and sessile at the base or the lowest petioled, repand-denticulate, or rarely nearly entire, 1'-4' long; flowers yellow, diurnal, 1'-2' broad, in terminal leafy-bracted spikes; calyx-segments lanceolate, spreading, the tube mostly longer than the ovary; petals obcordate; capsule sessile or short-stalked, oblong, prominently winged, glabrous or pubescent, 3"-4" long.
In dry soil, New Hampshire to Georgia, west to Minnesota and Louisiana. Recorded from Nova Scotia. Wild beet. Scabish. June-Aug.
Kneiffia Sumstinei Jennings, of western Pennsylvania, seems to be a race of this species with abundant long hairs, probably not distinct from Oenothera pilosella Raf.
Oenothera glauca Michx. Fl. Bor. Am. 1: 224. 1803.
Erect, glabrous and glaucous, 1 1/2°-3° high. Leaves sessile or the lower petioled, ovate or oval, repand-denticulate, 2'-5' long, 5" - 15" wide, acute or acutish at the apex, narrowed or rounded at the base; flowers bright yellow, diurnal, 1 1/2'-3' broad, very showy in short, leafy corymbs; petals broadly obovate, emarginate; calyx-lobes ovate-lanceolate, acuminate, spreading, its tube very slender and 5-8 times as long as the ovary; capsule oblong, broadly 4-winged, glabrous, 5"-6" long, borne on a short stalk.