Oenothera pilosella
Oenothera dodgeniana
meadow evening-primrose
spreading or ascending, unbranched or few-branched distally, 20–80 cm.
1 or few-branched from base, 50–120 cm.
in a basal rosette and cauline, basal 4–8 × 2–5 cm, petiole (0.5–)1–3(–4) cm, blade oblanceolate to ovate, margins entire;
cauline 3–10(–13) × 1–2(–4) cm, petiole 0–0.5(–2) cm, blade lanceolate to ovate, abruptly narrowed to base, margins subentire or coarsely dentate.
in a basal rosette and cauline, basal 6–20 × 1–3 cm, blade lanceolate to narrowly elliptic;
cauline 5–10 × 1–2.5 cm, blade lanceolate to narrowly elliptic, margins subentire or repand-denticulate.
erect, flowers in axils of distalmost few nodes.
opening near sunrise;
buds with free tips 1–3 mm, spreading;
floral tube 10–25 mm;
sepals 10–20 mm;
petals bright yellow, fading pale pink or pale yellow, 15–30 mm;
filaments 7–15 mm, anthers 4–8 mm, pollen 85–100% fertile;
style 10–20 mm, stigma exserted beyond anthers at anthesis.
4-merous, zygomorphic, opening at sunset;
floral tube 10–11 mm;
sepals 11–15 mm;
petals white, fading pink, rhombic-obovate, 11–14 mm;
filaments 6.5–9 mm, anthers 2.5–4 mm, pollen 90–100% fertile;
style 22–28 mm, stigma exserted beyond anthers.
usually oblong-clavate to oblong-ellipsoid or ellipsoid, 4-angled or weakly 4-winged, (5–)10–15(–28) × 2–4(–5) mm, stipe (1–)3–5(–9) mm;
sessile.
ellipsoid or ovoid, sharply 4-angled, with deep furrows alternating with angles for 2–3 mm from apex, ribbed from base of furrow to base of fruit, 9–11 × 3–5 mm;
sessile.
1 × 0.5 mm.
2–4, yellowish to light brown, 2–3 mm.
= 56.
= 14.
Oenothera pilosella
Oenothera dodgeniana
Oenothera pilosella is widespread in cultivation in gardens and frequently escapes and becomes naturalized; the northern and eastern natural limits of O. pilosella are not clear. According to G. B. Straley (1977) the natural limits are from Wayne County, West Virginia, along the Ohio River and Erie County, New York, for the eastern limits, and Tuscola County, Michigan, and Manitowoc County, Wisconsin, for the northern limits. K. N. Krakos (2014), based on new field studies and phylogenetic data, found that O. pilosella does not form a monophyletic group with plants previously treated by Straley as O. pilosella subsp. sessilis in molecular analyses, and thus is here reinstated as the distinct species O. sessilis. Straley determined that O. pilosella is self-incompatible and an octoploid, one of the few in the genus.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Oenothera dodgeniana occurs in two disjunct areas: the western foothills of the San Juan Mountains in Archuleta and Huerfano counties, Colorado, and Rio Arriba County, New Mexico; and Sierra Blanca and Sacramento Mountains in Lincoln and Otero counties, south-central New Mexico. The species was collected once at Durango, La Plata County, Colorado (P. H. Raven and D. P. Gregory 1972[1973]), but has not since been recollected. Oenothera dodgeniana and O. coloradensis were considered by Raven and Gregory to represent a relict species along the eastern flank of the Rocky Mountains that arose from more widespread species farther to the east, such as O. filiformis. Oenothera dodgeniana belongs to a subclade which is sister to that containing O. coloradensis, and within that subclade is sister to O. demareei and O. lindheimeri (W. L. Wagner et al. 2013). Although O. dodgeniana is fairly closely related to O. coloradensis, the two taxa seem to have had independent origins that have led to distributions along the eastern flank of the Rocky Mountains. Oenothera dodgeniana is self-compatible (Raven and Gregory).
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Go Botany
IL Wildflowers
LA Plants
MI Flora
MO Plants
WildflowerSearch
iNaturalist
USDA Plants Database
