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Photo is of parent taxon

narrowleaf evening primrose

Photo is of parent taxon

narrowleaf evening primrose

Habit Herbs mostly glandular puberulent or glabrous, sometimes strigillose or villous on stems; from fibrous rootstock. Herbs moderately to densely strigillose, and/or sometimes glandular puberulent or villous; from fibrous or, sometimes, slightly fleshy rootstock or producing rhizomes.
Leaves

in a basal rosette and cauline, basal 3–12 × 0.5–3 cm, petiole 1–3 cm, blade oblanceolate to obovate, margins dentate to remotely denticulate;

cauline 2–6(–11) × (0.5–)1–2(–5) cm, sometimes glaucous;

petiole 0.1–2(–6) cm;

blade narrowly elliptic to broadly ovate, margins dentate to remotely denticulate.

basal 3–10 × 0.5–2 cm, petiole 1–4 cm, blade oblanceolate to obovate, margins subentire or weakly and remotely denticulate;

cauline 2–6(–8) × 0.1–1(–1.7) cm, petiole 0.2–2(–4) cm, blade linear, lanceolate to oblanceolate, narrowly elliptic, or narrowly ovate, margins subentire or weakly and remotely denticulate.

Flowers

buds with free tips (3–)4–8(–13) mm, connivent to spreading;

floral tube 5–20 mm;

sepals 8–22 mm;

petals (8–)15–20(–30) mm.

buds with free tips 0.5–1(–6) mm, usually connivent, sometimes spreading;

floral tube5–15 mm;

sepals 5–20 mm;

petals (8–)15–25 mm.

Capsules

oblong to oblong-ellipsoid, widest at middle, (5–)10–17(–20) × (2–)3–4(–6) mm, 4-winged, sometimes 4-angled, stipe 0.1–3(–7) mm;

sessile.

clavate to oblong-clavate, widest distal to middle, angled, rarely narrowly winged, (5–)10–17(–20) × (2–)3–4 mm, stipe 3–10 mm;

sessile.

2n

= 28.

= 28, 42.

Oenothera fruticosa subsp. tetragona

Oenothera fruticosa subsp. fruticosa

Phenology Flowering Apr–Aug(–Sep). Flowering Apr–Aug(–Sep).
Habitat Open meadows, stream margins, edges of woods, open woods. Open habitats, meadows, stream margins, edges of woods, open woods, margins of freshwater or saltwater marshes, stabilized sand dunes, roadsides, partially disturbed habitats.
Elevation (100–)300–1700 m. ((300–)1000–5600 ft.) 0–500(–1100) m. (0–1600(–3600) ft.)
Distribution
from FNA
AL; CT; DC; DE; GA; IL; IN; KY; LA; MA; MD; ME; MI; MO; NC; NH; NY; OH; PA; RI; SC; TN; VA; WV; NS; ON; QC
from FNA
AL; AR; CT; DC; DE; FL; GA; IL; IN; KY; LA; MA; MD; MO; MS; NC; NY; OH; OK; PA; SC; TN; VA; WV
[BONAP county map]
Discussion

Oenothera serotina Sweet (1826) is a homonym, not Lehmann (1826), while Kneiffia floribunda Spach (1835) is an illegitimate substitution based on O. tetragona, and both names pertain here.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Kneiffia suffruticosa Spach (1835) is an illegitimate substitution for Oenothera fruticosa, as is K. angustifolia Spach (1835) one for O. linearis Michaux, and O. linearis var. allenii Britton (1894) is one based on O. fruticosa var. humifusa.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Source FNA vol. 10. FNA vol. 10.
Parent taxa Onagraceae > subfam. Onagroideae > tribe Onagreae > Oenothera > sect. Kneiffia > Oenothera fruticosa Onagraceae > subfam. Onagroideae > tribe Onagreae > Oenothera > sect. Kneiffia > Oenothera fruticosa
Sibling taxa
O. fruticosa subsp. fruticosa
O. fruticosa subsp. tetragona
Synonyms O. tetragona, Kneiffia fraseri, K. fruticosa var. differta, K. glauca, K. latifolia, K. serotina, K. tetragona, K. tetragona var. hybrida, O. ambigua, O. canadensis, O. fraseri, O. fruticosa var. ambigua, O. fruticosa var. differta, O. fruticosa var. fraseri, O. fruticosa subsp. glauca, O. fruticosa var. glauca, O. fruticosa var. incana, O. fruticosa var. maculata, O. glauca, O. glauca var. fraseri, O. hybrida, O. hybrida var. ambigua, O. incana, O. serotina, O. tetragona var. fraseri, O. tetragona subsp. glauca, O. tetragona var. hybrida, O. tetragona var. latifolia Kneiffia allenii, K. arenicola, K. brevistipata, K. charlesii, K. fruticosa var. humifusa, K. fruticosa var. unguiculata, K. linearis, K. longipedicellata, K. semiglandulosa, K. subglobosa, K. tetragona var. longistipata, K. velutina, O. fruticosa var. eamesii, O. fruticosa var. goodmanii, O. fruticosa var. humifusa, O. fruticosa var. linearifolia, O. fruticosa var. linearis, O. fruticosa var. microcarpa, O. fruticosa var. subglobosa, O. fruticosa var. unguiculata, O. fruticosa var. vera, O. linearis, O. linearis var. eamesii, O. longipedicellata, O. subglobosa, O. subglobosa var. arenicola, O. tetragona var. brevistipata, O. tetragona var. longistipata, O. tetragona var. sharpii, O. tetragona var. velutina, O. unguiculata
Name authority (Roth) W. L. Wagner: PhytoKeys 34: 16. (2014) unknown
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