Flora of the Southeastern United States

Petals rhombic-ovate to elliptic, widest near midlength, acute to broadly rounded; seeds ellipsoid, regularly pitted, borne ascending in locules; leaf margins deeply sinuate-lobed to subentire; [subsection Candela].

Petals 5-17 mm long; stigmas surrounded by anthers at anthesis; pollen ca. 50% fertile.

Inflorescence dense, with > 2 flowers per spike opening each day; leaves gray-green; [midwestern, south to KY and AR, or as a waif southwards and eastwards]

Inflorescence lax, 1-2 flowers per spike opening on each day; leaves green; [southeastern Coastal Plain]

Petals 15-35mm; stigmas exserted well beyond anthers at anthesis; pollen 85-100% fertile.

Pedicels, sepals, and capsules densely to sparsely appressed-strigillose, sometimes also with a few stipitate glands; mature flower buds not overtopping spike apex; free sepal tips 0.5-1.5 mm long; petals mostly bluntly acute to short-acuminate; [primarily of the Great Plains and Midwest, southwest to AK, IL, e. TX, and nw. LA]

Pedicels, sepals, and capsules usually glandular-puberulent, spreading-villous, hirsute with pustulate-based hairs, or glabrate; mature flower buds overtopping spike apex; free sepal tips 1-6 mm long; petals mostly broadly rounded; [primarily southeastern, e. TX north to AK and east to AL].

Inflorescences loose, unbranched; bracts 0.5-1.7 cm long, shorter than capsules; capsules hispid with pustular-based hairs; flower buds with free sepal tips 1-3 mm long, glandular-puberulent but not hispid; [endemic to se. TX]

Inflorescences dense, often branched; bracts 1-3 cm long, longer than capsules; [more widespread].

Flower buds with free sepal tips 2-6 mm long, divergent; flower buds, ovaries, or capsules at least sparsely hirsute with spreading, pustulate-based hairs, often also glandular-puberulent; [e. TX east to LA and sw. AK, introduced in MO]

Flower buds with free sepal tips 1-3 mm long, erect; flower buds, ovaries, and capsules glabrate or glandular-puberulent; [endemic to AL and MS]

Petals obcordate, widest near the apex, deeply to shallowly emarginate (rarely truncate); seeds prismatic and angled, irregularly pitted, borne horizontally in locules; leaf margins remotely dentate to subentire, or weakly sinuate-dentate near base; [subsection Oenothera].

Stigma well-elevated above the anthers at anthesis; petals (2.5-) 3-5 cm long; anthers 8-22 mm long; pollen 90-100% fertile (except O. glazioviana).

Cauline leaves 0.4-1.0 cm wide; apex of the inflorescence curved; free sepal tips subterminal, divergent; capsules spreading at nearly right angles to the stem, conspicuously curved upward, long-attenuate

Cauline leaves 1.5-6 cm wide; apex of the inflorescence erect; free sepal tips terminal, erect; capsules erect or slightly spreading.

Floral tubes (6-) 8-12 cm long, styles 9-17 (-20) cm long, buds 7-12 mm in diameter; capsules 6-12 mm in diameter; plants predominately densely appressed-strigillose (sometimes also glandular-puberulent in the inflorescence and sparsely appressed-villous), lacking or rarely with a few pustulate-based hairs; [TX, OK, and NE]

Floral tubes (2-) 3-4.5 (-5) cm long, styles 5-9 cm long, buds 5-10 mm in diameter; capsules 3.5-7 mm in diameter; plants usually with spreading, pustulate-based hairs in addition to the strigillose pubescence, or appearing nearly glabrous to the unaided eye.

Upper stems, ovaries, and floral tubes often appearing glabrous to unaided eye, sometimes glandular-puberulent, rarely somewhat strigillose; pustulate-based hairs absent or scattered and translucent; sepals yellow-green

Upper stems, ovaries, and floral tubes conspicuously strigillose and villous, also sometimes glandular-puberulent; pustulate-based hairs reddish-based (when fresh), often abundant; sepals often reddish-striped or flushed with red

Cauline leaves 2.5-4 cm wide, bright to dark green, usually with strongly crinkled margins; pollen ca. 50% fertile; ca. 50% of seeds abortive; [exotic; uncommonly cultivated, rarely naturalizing]

Cauline leaves 1-2.5 cm wide, dull green or gray-green, not crinkled; pollen 90-100% fertile; few seeds abortive; [native; TX and OK westward]

Stigma surrounded by or below the anthers at anthesis; petals 0.7-2.5(-3) cm long; anthers 3-10 mm long; pollen ca. 50% fertile.

Free sepal tips subterminal (or terminal in O. nutans) in bud, 0.5-5 mm long, usually divergent; inflorescences often curved at apex; capsules rusty brown or greenish black when dry; [primarily of the Northeast and Upper Midwest, south to n. GA and nw. SC in the mountains].

Stems densely silky-strigillose, the hairs appressed, sometimes also with scattered pustular-based hairs distally; leaf blades grayish-green; dry capsules rusty-brown; leaves 0.5-3 cm wide

Stems often nearly glabrous in inflorescence, predominantly villous and glandular-puberulent, sometimes also sparsely strigillose; leaf blades bright green; dry capsules greenish-black or dull green; leaves (1-) 1.5-7 cm wide.

Petals 0.8-1.5 (-2) cm, fading pale yellow or orange; bracts persistent, green; free sepal tips subterminal in bud; capsules usually greenish-black when dry

Free sepal tips terminal in bud, 0.5-3mm long, erect or slightly divergent; inflorescences erect at apex; capsules dull greenish or gray-green when dry; [collectively widespread].

Stems conspicuously and often densely strigillose, villous, and/or glandular-puberulent throughout, hairs with reddish pustular bases often abundant.

Stems, leaves, ovaries, capsules, and corolla tubes sparsely to moderately strigillose and glandular puberulent, usually also with abundant spreading, pustular-based hairs; leaves green; sepals usually green or yellowish; [mostly east of the Mississippi River]

Stems, leaves, ovaries, capsules, and corolla tubes densely strigillose, appearing exclusively appressed-pubescent without magnification (also with some appressed or subappressed pustular-based hairs and rarely glandular-puberulent in the inflorescence); leaves grayish-green; sepals usually red-striped or flushed red; [mostly west of the Mississippi River, scattered eastward as an introduction]