Jepson eFlora: Taxon page
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Epilobium oreganum
OREGON FIREWEED

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 oreganum Greene
NATIVE
Habit: Perennial herb 4--10 dm from leafy, basal shoots, +- glabrous, +- glaucous. Leaf: 30--90 mm, narrow-lanceolate to -ovate; veins +- red, conspicuous; petiole 1--3 mm. Inflorescence: open, sparsely glandular. Flower: hypanthium 2--3 mm; sepals 6--10 mm; petals (6)10--15 mm, pink to rose-purple; stamens < pistil; stigma 4-lobed. Fruit: 25--45 mm, hairy and glandular; pedicel 3--6 mm. Seed: 0.9--1.3 mm, ridged, hair-tuft deciduous. Chromosomes: 2n=36.
Ecology: Bogs, small streams; Elevation: 550--1800 m. Bioregional Distribution: KR, NCoRO; Distribution Outside California: southwestern Oregon. Flowering Time: Jul--Aug Note: Often confused with Epilobium ciliatum, especially Epilobium ciliatum subsp. glandulosum.
Synonyms: Epilobium exaltatum Drew
eFlora Treatment Author: Peter C. Hoch
Jepson Online Interchange
Listed on CNPS Rare Plant Inventory

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Next taxon: Epilobium oregonense

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Citation for this treatment: Peter C. Hoch 2016. Epilobium oreganum, in Jepson Flora Project (eds.) Jepson eFlora, http://ucjeps.berkeley.edu/cgi-bin/get_IJM.pl?tid=24383, accessed on February 06, 2016.

Citation for the whole project: Jepson Flora Project (eds.) 2016. Jepson eFlora, http://ucjeps.berkeley.edu/IJM.html, accessed on February 06, 2016.


Epilobium oreganum
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© 1997 Julie Kierstead Nelson
Epilobium oreganum
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© 2008 Keir Morse
Epilobium oreganum
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© 2015 Steve Matson
Epilobium oreganum
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© 2015 Steve Matson
Epilobium oreganum
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© 2008 Keir Morse
Epilobium oreganum
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© 2012 Julie Kierstead Nelson

More photos of Epilobium oreganum in CalPhotos


Geographic subdivisions for Epilobium oreganum:
KR, NCoRO;
Markers link to CCH specimen records. If the markers are obscured, reload the page [or change window size and reload]. Yellow markers indicate records that may provide evidence for eFlora range revision or may have georeferencing or identification issues.
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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.