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wood fruit evening primrose, woodyfruit evening primrose

Oakes' evening-primrose

Habit Herbs perennial, acaulescent, densely short-hirsute, also sometimes sparsely long-hirsute distally; from a thick, fleshy taproot. Herbs biennial, densely silky-strigillose, at least proximally, also sparsely villous with long, appressed hairs, sometimes also villous with spreading, pustulate hairs and/or glandular puberulent distally.
Stems

erect to decumbent, green or flushed with red on proximal parts or throughout, unbranched or bushy and branched from base, with side branches arising obliquely or arcuately from rosette, 10–60 cm.

Leaves

in a basal rosette, 2.6–4.2(–6.2) × 1.4–4.2 cm;

petiole 2.5–9(–11.5) cm;

blade usually oblanceolate to obovate, sometimes suborbiculate, margins dentate, pinnately lobed, lateral lobes oblong to lanceolate, often absent or reduced to only a few lobes toward terminal lobe, base rounded to cordate.

in a basal rosette and cauline, basal 8–30 × 0.5–3 cm, cauline 3.5–20 ×0.5–2.7 cm;

blade grayish green to dull green, very narrowly oblanceolate to narrowly oblanceolate or narrowly elliptic, margins flat, subentire or remotely dentate, teeth sometimes blunt, sometimes sinuate-dentate proximally;

bracts persistent.

Inflorescences

usually recurved with ascending tip distally, rarely suberect, unbranched.

Flowers

usually 1–3, rarely more, opening per day near sunset;

buds erect, quadrangular, without free tips;

floral tube 27–45(–55) mm;

sepals 25–30 mm;

petals intensely yellow, fading deep salmon red, obcordate, 25–38 mm;

filaments 17–23 mm, anthers 7–10 mm;

style 44–65(–80) mm, stigma somewhat exserted beyond anthers at anthesis.

opening near sunset;

buds erect, 3–5 mm diam., with free tips subterminal, spreading to erect, 2.5–4 mm;

floral tube 15–40 mm;

sepals green to yellow, flushed with red and dark red flecked or red-striped, 9–17 mm;

petals yellow to pale yellow, fading yellowish white to pale yellowish orange, very broadly obcordate, 7–20 mm;

filaments 6–15 mm, anthers 3–7 mm, pollen ca. 50% fertile;

style 20–45 mm, stigma surrounded by anthers at anthesis.

Capsules

moderately thin and flexible, lanceoloid, falcate or sigmoid, often contorted and twisted, 4-angled, 35–90 × 7–11 mm, gradually tapering to a long, slender, sterile apex, 10–30(–40) mm, valves conspicuously wrinkled, dehiscent 2/3–3/4 their length;

sessile.

erect or slightly spreading, usually rusty brown when dry, narrowly lanceoloid to lanceoloid, 15–40 × 4–8 mm, free tips of valves 0.5 mm.

Seeds

numerous, in 1 row per locule, often forming 2 rows near base of capsule, obovoid, 2.4–3.2 × 1.3–1.7 mm, surface coarsely rugose.

1.1–1.2 ×0.8–1 mm.

2n

= 14.

= 14.

Oenothera xylocarpa

Oenothera oakesiana

Phenology Flowering Jun–Jul(–Aug). Flowering Jun–Aug.
Habitat Open meadows, flats or slopes on loose granitic gravel, sand, or pumice in Pinus jeffreyi forests with Artemisia tridentata, or in Pinus contorta subsp. murrayana and Abies magnifica forests. Sandy coastal meadows and dunes, gravelly or rocky sites along rivers, disturbed sites, roadsides.
Elevation 2200–3100 m. (7200–10200 ft.) 0–50(–500) m. (0–200(–1600) ft.)
Distribution
from FNA
CA; NV
[BONAP county map]
from FNA
CT; DC; DE; IL; IN; MA; MD; ME; MI; MN; NH; NJ; NY; OH; PA; RI; VA; VT; WI; MB; NB; NF; NS; ON; PE; QC [Introduced in Europe, Asia]
[WildflowerSearch map]
[BONAP county map]
Discussion

Oenothera xylocarpa is known from three disjunct areas in California and adjacent Nevada: Mount Rose, Washoe County, Nevada; southern Sierra Nevada, southwestern Mono County, California, from the vicinity of Crestview south to Casa Diablo; and the area in the southern Sierra Nevada bounded by Horseshoe and Big Whitney meadows to the east and north, and Casa Vieja and Volcano Meadows to the south and west, west-central Inyo and eastern Tulare counties, California.

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

Oenothera oakesiana is a PTH species and forms a ring of 14 chromosomes or a ring of 12 and 1 bivalent in meiosis, and is self-compatible and autogamous (W. Dietrich et al. 1997). It has plastome IV and a AC genome composition.

(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. Contortae 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. 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. 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. 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. 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. 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
Synonyms Anogra xylocarpa O. biennis var. oakesiana, O. ammophila, O. ammophiloides, O. ammophiloides var. angustifolia, O. ammophiloides var. laurensis, O. atrovirens var. ostreae, O. canovirens var. cymatilis, O. cruciata var. stenopetala, O. cymatilis, O. deflexa var. bracteata, O. disjuncta, O. eriensis, O. eriensis var. niagarensis, O. eriensis var. repandodentata, O. germanica, O. insignis, O. laevigata var. rubripunctata, O. leucophylla, O. litorea, O. magdalena, O. millersii, O. muricata var. parviflora, O. niagarensis, O. nobska, O. oakesiana var. nobska, O. oakesiana var. tidestromii, O. ostreae, O. parviflora var. oakesiana, O. perangusta, O. perangusta var. rubricalyx, O. repandodentata, O. rubescens, O. stenopetala, O. tidestromii, Onagra oakesiana
Name authority Coville: Contr. U.S. Natl. Herb. 4: 105, plate 8. (1893) (A. Gray) J. W. Robbins ex S. Watson & J. M. Coulter in A. Gray et al.: Manual ed. 6, 190. (1890)
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