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Wolf's evening-primrose

Howard's evening-primrose

Habit Herbs biennial or short-lived perennial, densely strigillose, also villous with spreading to subappressed hairs, hairs sometimes pustulate, also glandular puberulent distally. Herbs acaulescent or sometimes caulescent, moderately to densely strigillose and glandular puberulent, sometimes also sparsely to moderately hirsute; from a taproot, sometimes lateral roots producing adventitious shoots.
Stems

erect, green, flushed with red proximally or red throughout, unbranched or branches obliquely arising from rosette and sometimes secondary branches arising from main stem, 50–100 cm.

(when present) ascending, longer ones becoming decumbent, leafy, sometimes densely so, 0–10(–30) cm.

Leaves

in a basal rosette and cauline, basal 13–35 ×1.5–4(–5) cm, cauline 5–18 × 1–2.5(–4) cm;

blade dull green, flat, oblanceolate to narrowly lanceolate or lanceolate to elliptic, margins bluntly dentate or subentire, teeth widely spaced or sinuate proximally;

bracts persistent.

in a basal rosette, sometimes also cauline, (6–)8.5–17(–23) × (0.5–)1–2(–3) cm;

petiole 2–7.5 cm;

blade usually oblanceolate, elliptic to narrowly oblong, rarely lanceolate, margins often undulate, entire or remotely and irregularly pinnately lobed mostly in proximal 1/2, rarely more regularly pinnately lobed and lobing extending to distal 1/2, sinuses usually extending less than 1/2 to midrib, lobes triangular to oblong or linear, (1–)4–9(–13) mm, apex acute to obtuse.

Inflorescences

erect, unbranched.

Flowers

opening near sunset;

buds erect, 5–8 mmdiam., with free tips terminal, erect, 1–3 mm;

floral tube 30–46 mm;

sepals yellowish green, also usually flushed with red or red-striped, 17–28 mm;

petals yellow, fading orange, pale yellow and somewhat opaque, very broadly obcordate, 13–23 mm, conspicuously shorter than sepals;

filaments 12–20 mm, anthers 7–12 mm, pollen ca. 50% fertile;

style 43–58 mm, stigma usually slightly exserted beyond anthers or surrounded by them at anthesis.

usually 1 or 2, rarely more, opening per day near sunset, strongly and sweetly scented;

buds with unequal free tips 1–3(–4) mm;

floral tube (43–)60–110(–125) mm;

sepals (30–)35–60(–80) mm;

petals brilliant yellow, fading deep red, drying deep reddish purple to reddish brown, usually broadly obovate, rarely subrhombic, (30–)40–60(–73) mm, sometimes with a terminal tooth;

filaments (19–)25–38 mm, anthers 10–17 mm;

style(90–)110–145(–165) mm, stigma exserted beyond anthers at anthesis.

Capsules

erect or slightly spreading, dark dull green and sometimes red-striped when dry, narrowly lanceoloid, 30–48 × 5–7 mm, free tips of valves 0.5–2.5mm.

leathery, ovoid, narrowly ovoid, or narrowly lanceoloid to broadly ellipsoid, winged, wings (2–)4–7(–11) mm wide, body (20–)25–50(–80) × 4–6 mm, dehiscent 1/4–1/3 their length;

pedicel 2–6 mm.

Seeds

0.9–2 × 0.9–1.3 mm.

numerous, usually in 1 row per locule, rarely in 2 rows toward base, obovoid to subcuboid, 3–8 × 2.5–3.5 mm.

2n

= 14.

= 28, 42, 56.

Oenothera wolfii

Oenothera howardii

Phenology Flowering Jun–Oct. Flowering May–Jul.
Habitat Coarse-textured sandy or rocky sites, coastal dunes and bluffs, loose, sandy sites along roads, moist places. Open or rocky areas, in shale, fine-textured sandstones, clays, gypsum, or limestone from High Plains grasslands, open sites in pinyon-juniper woodlands, ponderosa pine-Douglas fir forests.
Elevation 0–100(–800) m. (0–300(–2600) ft.) (1000–)1500–2300(–3000) m. ((3300–)4900–7500(–9800) ft.)
Distribution
from FNA
CA; OR
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[BONAP county map]
from FNA
CO; KS; NV; UT; WY
[WildflowerSearch map]
[BONAP county map]
Discussion

Oenothera wolfii is a PTH species and forms a ring of 14 chromosomes in meiosis, and is self-compatible and autogamous (W. Dietrich et al. 1997). It has plastome I and a AA genome composition. It is known only from the vicinity of Port Orford, Curry County, Oregon (currently apparently only as far north as Otter Rock), south in a scattered distribution through Del Norte County to the mouth of the Mattole River, Humboldt County, California. The distribution, at least in California, is closely associated with small patches of Cenozoic-age marine sediments, isolated from each other by Franciscan sedimentary and metamorphic rocks. Most populations appear to occur near river mouths or to the south of a headland. The largest populations center in the area about 11 km long in the vicinity of Crescent City in Del Norte County, between Point George and Enderts Beach in Redwood National Park. There are collections from two inland California localities, one at the eastern border of Humboldt County, California (Willow Creek, Trinity River Valley), and the other at Carville, Trinity County, that may be O. wolfii. If so, they would presumably represent recent introductions and should be studied further. As summarized by Dietrich et al., O. wolfii is a rare endemic of coastal habitats and known from about 20 different sites. The total number of individuals of O. wolfii apparently fluctuates, with perhaps no more than about 5000 individuals total. It is threatened by any potential development and alteration of its habitat, presently by road maintenance and foot traffic. Another possibly more serious threat comes from the recent spread of O. glazioviana to this area. Oenothera glazioviana could swamp populations through hybridization and, perhaps, by direct competition.

Oenothera wolfii is in the Center for Plant Conservation’s National Collection of Endangered Plants.

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

Oenotherahowardii is known from three disjunct areas: three collections on the High Plains (Baca and Otero counties, Colorado, and Hamilton County, Kansas); open yucca-juniper grassland, rocky slopes or disturbed areas on shale substrates along the Colorado counties of Boulder, Denver, Jefferson, and Larimer, and just over the state line in Wyoming; and, common to scattered, mostly on rocky slopes but also in shaded canyon sites on fine-textured red sandstones, clays, gypsum, chalky white degraded limestone or limestone in pinyon-juniper woodland to ponderosa pine-Douglas fir forest in southern Utah and eastern Nevada.

A. Nelson intended to publish Lavauxia howardii as a new combination and base it on Oenothera howardii M. E. Jones (1893), which was not validly published at the time, but inadvertently published L. howardii as a new species. Oenothera howardii (A. Nelson) W. L. Wagner is an isonym.

(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. Oenothera > subsect. Oenothera Onagraceae > subfam. Onagroideae > tribe Onagreae > Oenothera > sect. Megapterium
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. 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. glazioviana, O. grandiflora, O. grandis, O. harringtonii, O. hartwegii, O. havardii, O. heterophylla, O. hispida, 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
Synonyms O. hookeri subsp. wolfii, Var. o. var. o. Lavauxiahowardii a.
Name authority (Munz) P. H. Raven, W. Dietrich & Stubbe: Syst. Bot. 4: 244. (1980) (A. Nelson) M. E. Jones ex Prain in B. D. Jackson et al.: Index Kew., suppl. 3: 121. (1908) — (as howardi)
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