Oenothera wolfii
Oenothera californica
Wolf's evening-primrose
California evening primrose
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.
ascending or decumbent, usually branched from near base, sometimes new rosettes forming at branch apex when buried in drifting sand, 10–60 cm.
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 and cauline, rosette sometimes weakly developed or absent, at least during flowering, 1–13 × 0.5–2 cm;
petiole 0–2(–4.5) cm;
blade oblong to oblanceolate or spatulate, sometimes rhombic-ovate, margins entire or weakly to conspicuously dentate or pinnatifid.
erect, unbranched.
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.
1–several opening per day near sunset;
buds nodding, weakly quadrangular, with free tips 0–0.8 mm;
floral tube 20–40 mm;
sepals 15–30 mm, not spotted;
petals white, fading pink to deep pink, broadly obcordate, 15–35(–40) mm;
filaments 10–17 mm, anthers 5–10 mm;
style 30–60 mm, stigma exserted beyond anthers at anthesis.
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.
spreading to ascending, woody in age, often curved upward, cylindrical, obtusely 4-angled, tapering slightly from base to apex, 20–80 × 2–3.5 mm;
sessile.
0.9–2 × 0.9–1.3 mm.
numerous, in 1 row per locule, olive-brown or yellowish brown to black, sometimes with minute purple dots, obovoid, 1–2.5 mm.
= 14.
Oenothera wolfii
Oenothera californica
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.)
Subspecies 3 (3 in the flora).
Most populations of Oenothera californica are self-incompatible (W. L. Wagner et al. 2007; K. E. Theiss et al. 2010), but some populations of subsp. californica are self-compatible. All chromosome counts indicate that subspp. avita and eurekensis are diploid (2n = 14) and those of subsp. californica are tetraploid (2n = 28). Oenothera californica is polymorphic with subspp. avita and californica being very similar, and differing primarily in ecology, distribution, and relatively minor differences in leaf morphology and ploidy level, while the sand dune-restricted subsp. eurekensis is more distinctive in both morphology and habitat.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
1. Plants with fleshy underground horizontal rootstocks; stems sometimes with new rosettes forming at stem apex when becoming buried in drifting sand; leaf blades rhombic-ovate to oblanceolate, margins entire or weakly dentate. | subsp. eurekensis |
1. Plants with a taproot and adventitious shoots from lateral roots; stems not with new rosettes forming at branch apex; leaf blades oblong to oblanceolate to spatulate, margins entire or weakly to conspicuously dentate or pinnatifid. | → 2 |
2. Leaf blade margins usually entire or weakly dentate, sometimes more conspicuously dentate to pinnatifid; capsules 30–55 mm. | subsp. californica |
2. Leaf blade margins conspicuously dentate to pinnatifid, rarely some or all of them entire or weakly dentate; capsules 20–80 mm. | subsp. avita |
CA
OR
Flora NW
PNW Herbaria
WildflowerSearch
iNaturalist
USDA Plants Database
