familyOnagraceae
subfamilyOnagraceae subfam. Onagroideae
tribeOnagraceae tribe Onagreae
genusOenothera
sectionOenothera sect. Kneiffia
speciesOenothera pilosella

Oenothera pilosella

Rafinesque

Ann. Nat. 1: 15. 1820.

Warren L. Wagner
Synonyms: Kneiffia fruticosa var. pilosella (Rafinesque) Britton K. pilosella (Rafinesque) A. Heller K. pratensis Small K. sumstinei Jennings Oenothera fruticosa var. hirsuta Nuttall ex Torrey & A. Gray O. fruticosa var. pilosella (Rafinesque) Small & A. Heller O. pratensis (Small) B. L. Robinson
Treatment appears in FNA Volume 10.
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Herbs perennial, usually densely to sparsely hirsute, rarely glabrous; from a thickened base, rhizomatous. Stems spreading or ascending, unbranched or few-branched distally, 20–80 cm. Leaves 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. Inflorescences erect, flowers in axils of distalmost few nodes. Flowers 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. Capsules 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. Seeds 1 × 0.5 mm. 2n = 56.


Phenology: Flowering May–Jul(–Aug).
Habitat: Open fields, edge of woods, marshes and bottomland prairies, open dis­turbed sites, ditches, old fields, railroads, roadsides.
Elevation: 100–600 m.

Distribution

Ont., Ala., Ark., Conn., Ill., Ind., Iowa, Ky., La., Maine, Mass., Mich., Miss., Mo., N.H., N.Y., Ohio, Okla., Pa., R.I., Vt., Va., W.Va., Wis.

Discussion

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.

Selected References

None.

Lower Taxa

None.
... more about "Oenothera pilosella"
RDF feed
2n chromosome quantity
56 +
4-locular septum architecture
incomplete +
4-locular septum architecture or structure in adjective form
1-locular +
Androecium position
epigynous +
Anther fixation
versatile +
Anther some measurement
0.4 cm4 mm <br />0.004 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
Apex architecture or shape
emarginate +
Apex shape
tapering +  and rounded to truncate +
Author
Warren L. Wagner +
Authority
Rafinesque +
Basal leaf arrangement
alternate +
Basal leaf position
cauline +
Basal leaf presence
absent +
Basal stem length
4 cm40 mm <br />0.04 m <br /> (8 cm80 mm <br />0.08 m <br />) +
Basal stem width
2 cm20 mm <br />0.02 m <br /> (5 cm50 mm <br />0.05 m <br />) +
Base coloration
pale green +  and yellow usually fading orange purple pale-yellow reddish or whitish +
Base reproduction
sterile +
Base shape
pedicel-like +
Basionyms
Kneiffia +
Berry architecture or shape
nutlike +
Berry dehiscence
indehiscent +  and loculicidal +
Blade margin shape
dentate +, denticulate +, subentire +  and entire +
Blade shape
narrowed +, lanceolate +  and ovate +
Bud orientation
spreading +
Bud shape
terete +
Capsule architecture
4-winged +
Capsule architecture or shape
nutlike +
Capsule architecture or structure in adjective form
4-locular +
Capsule atypical length
1.5 cm15 mm <br />0.015 m <br /> (2.8 cm28 mm <br />0.028 m <br />) +
Capsule atypical width
0.4 cm4 mm <br />0.004 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
Capsule condition or texture
dry +
Capsule course
straight +
Capsule dehiscence
indehiscent +  and dehiscent +
Capsule length
1 cm10 mm <br />0.01 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
Capsule shape
4-angled +, usually oblong-clavate +  and oblong-ellipsoid or ellipsoid +
Capsule texture
leathery +
Capsule width
0.2 cm2 mm <br />0.002 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
Carpel quantity
Many (?) +
Cel reproduction
vegetative +
Distalmost node quantity
few +
Distribution
Ont. +, Ala. +, Ark. +, Conn. +, Ill. +, Ind. +, Iowa +, Ky. +, La. +, Maine +, Mass. +, Mich. +, Miss. +, Mo. +, N.H. +, N.Y. +, Ohio +, Okla. +, Pa. +, R.I. +, Vt. +, Va. +, W.Va. +  and Wis. +
Elevation
100–600 m. +
Embryo-sac coating
oily +
Embryo-sac course
straight +
Embryo-sac presence
absent +
Embryo coating
oily +
Embryo course
straight +
Embryo presence
absent +
Endosperm coating
oily +
Endosperm course
straight +
Endosperm presence
absent +
Epidermis coloration
whitish +  and green +
Epidermis relief
exfoliating +
Filament architecture
dithecal +
Filament fixation
basifixed +  and versatile +
Filament fusion
distinct +
Filament some measurement
0.7 cm7 mm <br />0.007 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
Floral-tube duration
deciduous +
Floral-tube presence
absent +
Floral-tube pubescence
hispid +, lanate +  and glabrous +
Floral-tube quantity
, +
Floral-tube some measurement
1 cm10 mm <br />0.01 m <br /> (2.5 cm25 mm <br />0.025 m <br />) +
Flower architecture
zygomorphic +  and actinomorphic +
Flower architecture or arrangement or growth form
solitary +
Flower odor
scented +
Flower part duration
deciduous +
Flower part life cycle
anthesis +
Flower reproduction
bisexual +
Fruit architecture
winged +
Fruit course
curved +  and straight +
Fruit dehiscence
indehiscent +  and dehiscent +
Fruit shape
4-angled +, terete +, tapering +, cylindrical +, ellipsoid +, clavate +, ovoid ellipsoid +  and cylindrical rhombic-obovoid or globose +
Habitat
Open fields, edge of woods, marshes and bottomland prairies, open disturbed sites, ditches, old fields, railroads, roadsides. +
Hair height or length or size
short +
Hair position relational
interlocking +
Herb architecture
rhizomatous +
Herb duration
perennial +
Herb growth form
suffrutescent +
Herb pubescence
glabrous +  and hirsute +
Herb texture
fleshy +
Illustration
Present +
Indusium architecture
peltate +
Indusium prominence
conspicuous +
Inflorescence orientation
erect +
Inflorescence position
axillary +
Lateral root orientation
spreading +
Leaf-axil orientation
nodding +  and erect +
Leaf architecture
simple +
Leaf arrangement
alternate +
Leaf atypical some measurement
10 cm100 mm <br />0.1 m <br /> (13 cm130 mm <br />0.13 m <br />) +
Leaf condition
later +
Leaf duration
deciduous +
Leaf position
cauline +
Leaf presence
absent +
Leaf some measurement
3 cm30 mm <br />0.03 m <br /> (10 cm100 mm <br />0.1 m <br />) +
Lobe arrangement or course or shape
linear +
Lobe quantity
4 (?) +
Locule arrangement or growth form
clustered +
Locule quantity
many +
Margin architecture or shape
entire +
Margin position
cauline +
Margin shape
dentate +  and subentire +
Mouth condition
closing +
Nectary presence
absent +
Number of lower taxa
0 +
Ovary architecture
pedicellate +  and sessile +
Ovary architecture or structure in adjective form
1-locular +
Ovary position
inferior +
Ovule architecture
bitegmic +
Ovule arrangement or growth form
clustered +
Ovule orientation
anatropous +
Ovule quantity
1 +  and 8 +
Perianth position
epigynous +
Petal arrangement
imbricate +
Petal arrangement or shape
convolute +
Petal character
not color +
Petal coloration
pale-yellow +, fading pale-pink +  and bright-yellow +
Petal presence
absent +
Petal quantity
4 +
Petal shape
obcordate +  and obovate +
Petal some measurement
1.5 cm15 mm <br />0.015 m <br /> (3 cm30 mm <br />0.03 m <br />) +
Petiole atypical some measurement
0.5 cm5 mm <br />0.005 m <br /> (2 cm20 mm <br />0.02 m <br />) +
Petiole some measurement
0 cm0 mm <br />0 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
Phenology
Flowering May–Jul(–Aug). +
Pollen-grain dehiscence or orientation
longitudinal +
Pollen arrangement
singly +
Pollen reproduction
fertile +
Polyad arrangement
singly +
Proximal part reproduction
sterile +
Publication title
Ann. Nat. +
Publication year
1820 +
Raphide quantity
abundant +
Reference
None +
Rosette position
basal +  and cauline +
Row atypical quantity
2 (4) +
Row quantity
2 +  and 1 +
Secretion condition
wet +
Secretion condition or texture
dry +
Secretion relief
papillate +
Secretion shape
clavate +  and globose +
Seed arrangement or growth form
clustered +
Seed atypical quantity
1 (160) +
Seed length
1 cm10 mm <br />0.01 m <br /> (?) +
Seed quantity
numerous +
Seed relief
sculptured +  and smooth +
Seed shape
ovoid +
Seed size
reduced +
Seed width
0.5 cm5 mm <br />0.005 m <br /> (?) +
Sepal architecture or dehiscence
splitting +
Sepal arrangement
separating +
Sepal arrangement or dehiscence
valvate +
Sepal coloration
purple +, pink +, red +  and green +
Sepal duration
deciduous +
Sepal fusion
coherent +
Sepal orientation
reflexed +
Sepal quantity
4 +
Sepal some measurement
1 cm10 mm <br />0.01 m <br /> (2 cm20 mm <br />0.02 m <br />) +
Septum architecture
incomplete +
Septum arrangement
parietal +, axile +  and placentation +
Septum fragility
fragile +
Septum presence
absent +
Septum width
thin +
Series length or size
longer +
Series quantity
2 +
Series size
unequal +
Series variability
equal +
Set length or size
longer +
Set quantity
2 +
Set variability
equal +
Shoot orientation
arising +
Shrub architecture
unarmed +
Shrub growth form
not clonal +
Shrub habitat
aquatic +, amphibious +  and terrestrial +
Slit dehiscence or orientation
longitudinal +
Spike architecture
leafy +
Stamen quantity
8 +
Stamen size
in 2 unequal series +  and subequal +
Stamen size or quantity
2 times as many or as many as sepals +
Stem architecture
few-branched +  and unbranched +
Stem growth form or orientation
decumbent +
Stem orientation
ascending +  and spreading +
Stem some measurement
20 cm200 mm <br />0.2 m <br /> (80 cm800 mm <br />0.8 m <br />) +
Stigma architecture
peltate +
Stigma development
developing +
Stigma quantity
1 +
Stigma shape
divided +
Stipe architecture
sessile +
Stipe atypical some measurement
0.5 cm5 mm <br />0.005 m <br /> (0.9 cm9 mm <br />0.009 m <br />) +
Stipe some measurement
0.3 cm3 mm <br />0.003 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
Stipule architecture
petiolate +  and sessile +
Stipule duration
caducous +
Stipule position
intrapetiolar +
Stipule presence
absent +
Stipule size
small +
Style pubescence
pubescent +  and glabrous +
Style quantity
1 +
Style some measurement
1 cm10 mm <br />0.01 m <br /> (2 cm20 mm <br />0.02 m <br />) +
Subshrub architecture
unarmed +
Subshrub growth form
not clonal +
Subshrub habitat
aquatic +, amphibious +  and terrestrial +
Surface architecture
smooth +, reticulate +  and furrowed +
Surface architecture or shape
entire +
Surface condition
wet +
Surface duration
persisting +
Surface life cycle
anthesis +
Surface prominence
obscured +
Surface quantity
7 (?) +
Surface relief
papillose +
Surface shape
beaded +
Synonyms
Kneiffia fruticosa var. pilosella +, K. pilosella +, K. pratensis +, K. sumstinei +, Oenothera fruticosa var. hirsuta +, O. fruticosa var. pilosella +  and O. pratensis +
Taxon family
Onagraceae +
Taxon name
Oenothera pilosella +
Taxon parent
Oenothera sect. Kneiffia +
Taxon rank
species +
Tetrad arrangement
singly +
Tetrad dehiscence
3(-5)-aperturate +
Tip fusion
free +
Tip some measurement
0.1 cm1 mm <br />0.001 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
Valve midrib architecture
sessile +
Valve midrib dehiscence
dehiscent +
Valve midrib prominence
raised +
Viscin thread dehiscence or orientation
longitudinal +
Viscin thread fusion
united +
Volume
Volume 10 +
Wall texture
woody +  and hard +
Wing architecture
smooth +  and erose +
Wing condition or texture
dry +
Wing relief
papillate +
Wing width
thick +