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garden evening-primrose, large-flower evening primrose, red-sepal evening-primrose

Habit Herbs perennial (short-lived or, sometimes, suffrutescent) or annual, glabrous or strigillose; from a stout taproot. Herbs biennial, densely to sparsely strigillose and villous, with spreading, red-pustulate hairs, also glandular puberulent and with only a few appressed hairs near inflorescence.
Stems

1–many, weakly decumbent to ascending or erect, unbranched to moderately branched, (10–)25–80 cm.

erect, green or flushed with red on proximal parts, sometimes inflorescence axis red, usually withside branches obliquely arising from rosette and secondary branches from main stem, 50–150 cm.

Leaves

1–9 × (0.1–)0.3–1 cm, sometimes fascicles of small leaves to 2 cm present in non-flowering axils;

petiole 0–0.6 cm;

blade linear to narrowly lanceolate or oblanceolate, often folded lengthwise, usually not much reduced distally, proximalmost leaves sometimes spatulate, base attenuate, margins subentire or serrulate or spinulose-serrate, apex acute.

in a basal rosette and cauline, basal 13–30 × 3–5 cm, cauline 5–15 × 2.5–4 cm;

blade dark to bright green, white- or red-veined, narrowly oblanceolate to oblanceolate, sometimes narrowly elliptic to lanceolate distally, margins usually conspicuously crinkled, sometimes undulate, bluntly dentate, teeth widely spaced, sometimes sinuate-dentate proximally or lobed;

bracts persistent.

Inflorescences

erect, unbranched.

Flowers

opening at sunrise;

buds with free tips 0–4 mm;

floral tube 5–20 mm;

sepals 4–12 mm, midribs keeled;

petals yellow, fading orangish to purplish, 6–25 mm; antisepalous filaments 2–8 mm, antipetalous filaments 1–4 mm, anthers 2–7 mm, pollen 90–100% fertile;

style 9–30 mm, stigma sometimes blue-black, discoid to quadrangular, exserted beyond anthers.

opening near sunset;

buds erect, 7–9 mm diam., with free tips terminal, erect to spreading, 5–8 mm;

floral tube 35–50 mm;

sepals yellowish green, usually flushed with red or red-striped, sometimes very dark red throughout, 28–45 mm;

petals yellow to pale yellow, fading yellowish white and somewhat translucent, very broadly obcordate, 35–50 mm;

filaments 17–25 mm, anthers 10–12 mm, pollen ca. 50% fertile;

style 50–80 mm, stigma exserted beyond anthers at anthesis.

Capsules

10–35 × 1–2 mm, hard, dehiscent 1/2 their length, often tardily dehiscent throughout their length.

erect or slightly spreading, dull green when dry, lanceoloid, 20–35 × 5–6 mm, free tips of valves 0.8–1.5 mm.

Seeds

obovoid, 1–1.8 mm, sharply angled, apex truncate.

1.3–2 ×1–1.5 mm, ca. 50% abortive.

2n

= 14.

Oenothera capillifolia

Oenothera glazioviana

Phenology Flowering (Jun–)Jul–Sep(–Oct).
Habitat Open, disturbed sites.
Elevation 20–600(–1400) m. (100–2000(–4600) ft.)
Distribution
c United States; sc United States; n Mexico
from FNA
AL; AR; CA; CT; IL; IN; MA; ME; MI; MT; NC; NH; NJ; NY; OR; PA; RI; VT; WA; WI; WV; BC; MB; NS; ON; QC [Introduced in North America; introduced nearly worldwide in temperate and subtropical regions]
[WildflowerSearch map]
[BONAP county map]
Discussion

Subspecies 2 (2 in the flora).

Oenothera capillifolia is self-incompatible (H. F. Towner 1977).

Oenothera berlandieri (Spach) Steudel 1841, not D. Dietrich 1840, is superfluous and cannot be used in Oenothera when transferred from Calylophus, and pertains here.

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

Oenothera glazioviana originated by hybridization between two cultivated or naturalized species in Europe and was introduced into the horticultural trade by Carter and Company of England in 1860 (R. E. Cleland 1972; P. H. Raven et al. 1979). The oldest name applied to this entity was based on plants cultivated in Rio de Janeiro in 1868; clearly, O. glazioviana must have spread very rapidly.

Oenothera glazioviana is a PTH species and forms a ring of 12 chromosomes and 1 bivalent in meiosis, and is self-compatible and autogamous (W. Dietrich et al. 1997). It has plastome II or III and a AB genome composition.

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

Key
1. Stems 1–several, ascending to erect, 30–80 cm; leaves 2.5–9 cm.
subsp. capillifolia
1. Stems several–many, decumbent to ascending, (10–)25–40 cm; leaves 1–4 cm.
subsp. berlandieri
Source FNA vol. 10. FNA vol. 10.
Parent taxa Onagraceae > subfam. Onagroideae > tribe Onagreae > Oenothera > sect. Calylophus > subsect. Calylophus Onagraceae > subfam. Onagroideae > tribe Onagreae > Oenothera > sect. Oenothera > subsect. Oenothera
Sibling taxa
O. acutissima, O. albicaulis, O. argillicola, O. arida, O. arizonica, O. biennis, O. boquillensis, O. brachycarpa, O. calcicola, O. californica, O. canescens, O. cavernae, O. cespitosa, O. cinerea, O. clelandii, O. coloradensis, O. cordata, O. coronopifolia, O. coryi, O. curtiflora, O. curtissii, O. deltoides, O. demareei, O. dodgeniana, O. drummondii, O. elata, O. engelmannii, O. falfurriae, O. filiformis, O. filipes, O. flava, O. fruticosa, O. gaura, O. gayleana, O. glaucifolia, O. glazioviana, O. grandiflora, O. grandis, O. harringtonii, O. hartwegii, O. havardii, O. heterophylla, O. hispida, O. howardii, O. humifusa, O. jamesii, O. kunthiana, O. laciniata, O. lavandulifolia, O. lindheimeri, O. linifolia, O. longissima, O. macrocarpa, O. mckelveyae, O. mexicana, O. nealleyi, O. neomexicana, O. nutans, O. nuttallii, O. oakesiana, O. organensis, O. pallida, O. parviflora, O. patriciae, O. perennis, O. pilosella, O. platanorum, O. podocarpa, O. primiveris, O. psammophila, O. pubescens, O. rhombipetala, O. riparia, O. rosea, O. serrulata, O. sessilis, O. simulans, O. sinuosa, O. spachiana, O. speciosa, O. stricta, O. suffrutescens, O. suffulta, O. tetraptera, O. texensis, O. toumeyi, O. triangulata, O. triloba, O. tubicula, O. villosa, O. wolfii, O. xylocarpa
O. acutissima, O. albicaulis, O. argillicola, O. arida, O. arizonica, O. biennis, O. boquillensis, O. brachycarpa, O. calcicola, O. californica, O. canescens, O. capillifolia, O. cavernae, O. cespitosa, O. cinerea, O. clelandii, O. coloradensis, O. cordata, O. coronopifolia, O. coryi, O. curtiflora, O. curtissii, O. deltoides, O. demareei, O. dodgeniana, O. drummondii, O. elata, O. engelmannii, O. falfurriae, O. filiformis, O. filipes, O. flava, O. fruticosa, O. gaura, O. gayleana, O. glaucifolia, O. grandiflora, O. grandis, O. harringtonii, O. hartwegii, O. havardii, O. heterophylla, O. hispida, O. howardii, O. humifusa, O. jamesii, O. kunthiana, O. laciniata, O. lavandulifolia, O. lindheimeri, O. linifolia, O. longissima, O. macrocarpa, O. mckelveyae, O. mexicana, O. nealleyi, O. neomexicana, O. nutans, O. nuttallii, O. oakesiana, O. organensis, O. pallida, O. parviflora, O. patriciae, O. perennis, O. pilosella, O. platanorum, O. podocarpa, O. primiveris, O. psammophila, O. pubescens, O. rhombipetala, O. riparia, O. rosea, O. serrulata, O. sessilis, O. simulans, O. sinuosa, O. spachiana, O. speciosa, O. stricta, O. suffrutescens, O. suffulta, O. tetraptera, O. texensis, O. toumeyi, O. triangulata, O. triloba, O. tubicula, O. villosa, O. wolfii, O. xylocarpa
Subordinate taxa
O. capillifolia subsp. berlandieri, O. capillifolia subsp. capillifolia
Synonyms Meriolix capillifolia O. erythrosepala, O. grandiflora subsp. erythrosepala, Onagra erythrosepala
Name authority Scheele: Linnaea 21: 576. (1848) Micheli in C. F. P. von Martius et al.: Fl. Brasil. 13(2): 178. (1875)
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