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Epilobium densiflorum

Higher Taxonomy
Family: OnagraceaeView DescriptionDichotomous Key

Common Name: EVENING-PRIMROSE FAMILY
Habit: Annual to perennial herb (to tree). Leaf: cauline or basal, alternate, opposite, or whorled, generally simple and toothed (to pinnately compound); stipules 0 or generally deciduous. Inflorescence: spike, raceme, panicle, or flowers 1 in axils; bracted. Flower: generally bisexual, generally radial, often opening at either dawn or dusk; hypanthium generally prolonged beyond ovary (measured from ovary tip to sepal base); sepals 4(2--7); petals 4(2--7, rarely 0), often fading darker; stamens 2 × or = sepals in number, anthers 2-chambered, opening lengthwise, pollen interconnected by threads; ovary inferior, chambers generally as many as sepals (sometimes becoming 1), placentas axile or parietal, ovules 1--many per chamber, style 1, stigma 4-lobed (or lobes as many as sepals), club-shaped, spheric, or hemispheric. Fruit: capsule, loculicidal (sometimes berry or indehiscent and nut-like). Seed: sometimes winged or hair-tufted.
Genera In Family: 22 genera, +- 657 species: worldwide, especially western North America; many cultivated (Clarkia, Epilobium, Fuchsia, Oenothera). Note: Gaura moved to Oenothera. Fuchsia magellanica Lam. naturalized in northern California.
eFlora Treatment Author: Warren L. Wagner & Peter C. Hoch, family description, key to genera; treatment of genera by Warren L. Wagner, except as noted
Scientific Editor: Robert Patterson, Bruce G. Baldwin.
Genus: EpilobiumView DescriptionDichotomous Key

Common Name: WILLOWHERB
Habit: Annual to subshrub. Leaf: generally opposite proximally (or clustered in axils), generally +- fine-toothed; veins generally obscure. Inflorescence: generally raceme, bracted. Flower: radial or rarely +- bilateral; sepals 4, erect; petals 4, notched; stamens 8, anthers attached at middle, pollen grains generally shed in 4s, cream-yellow; ovary chambers 4, stigma generally club-like, occasionally 4-lobed. Fruit: straight, cylindric to club-like. Seed: generally in 1 row per chamber, generally with white, deciduous hair-tuft.
Species In Genus: 165 species: worldwide except tropics. Etymology: (Greek: upon pod, from inferior ovary) Note: Incl Boisduvalia, Zauschneria. Most taxa polyploid; many with anthers +- = stigma self-pollinated; many hybrids. Taxa with alternate leaves moved to Chamerion.
eFlora Treatment Author: Peter C. Hoch

Epilobium densiflorum (Lindl.) Hoch & P.H. Raven
NATIVE
Habit: Annual 0.5--15 dm, simple or branched distally, peeling proximally, spreading hairy or strigose. Leaf: opposite only near base, +- sessile, 14--85 mm, (narrowly) lanceolate to sublinear; distal leaves hairy. Inflorescence: leafy, +- dense spike, sometimes glandular. Flower: hypanthium 1.3--4 mm; sepals 2--8 mm; petals 3--10 mm, rose-purple to white; stigma head-like to irregularly 4-lobed. Fruit: 4--11 mm, cylindric, pliable, not beaked, dehiscent to base; axis persistent; pedicel 0--2.5 mm. Seed: 1.2--1.6(1.9) mm, netted, glabrous, hair-tuft 0. Chromosomes: 2n=20.
Ecology: Streambanks, outwashes, seasonal moist flats; Elevation: < 2600 m. Bioregional Distribution: CA-FP (exc SCo, ChI), MP; Distribution Outside California: to British Columbia, Montana, Arizona, northern Baja California. Flowering Time: May--Oct Note: Highly variable.
eFlora Treatment Author: Peter C. Hoch
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Citation for this treatment: Peter C. Hoch 2016. Epilobium densiflorum, in Jepson Flora Project (eds.) Jepson eFlora, http://ucjeps.berkeley.edu/cgi-bin/get_IJM.pl?tid=76884, accessed on May 26, 2016.

Citation for the whole project: Jepson Flora Project (eds.) 2016. Jepson eFlora, http://ucjeps.berkeley.edu/IJM.html, accessed on May 26, 2016.


Epilobium densiflorum
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© 2008 Keir Morse
Epilobium densiflorum
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© 2010 George W. Hartwell
Epilobium densiflorum
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© 2008 Neal Kramer
Epilobium densiflorum
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© 2006 George W. Hartwell
Epilobium densiflorum
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© 2005 Keir Morse
Epilobium densiflorum
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© 2015 Neal Kramer

More photos of Epilobium densiflorum in CalPhotos


Geographic subdivisions for Epilobium densiflorum:
CA-FP (exc SCo, ChI), MP;
Markers link to CCH specimen records. Yellow markers indicate records that may provide evidence for eFlora range revision or may have georeferencing or identification issues. Purple markers indicate specimens collected from a garden, greenhouse, or other non-wild location.
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map of distribution 1
(Note: any qualifiers in the taxon distribution description, such as 'northern', 'southern', 'adjacent' etc., are not reflected in the map above, and in some cases indication of a taxon in a subdivision is based on a single collection or author-verified occurence).

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Data provided by the participants of the Consortium of California Herbaria.
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CCH collections by month

Duplicates counted once; synonyms included.
Species do not include records of infraspecific taxa.
Blue line denotes eFlora flowering time.