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Bistorta bistortoides

Higher Taxonomy
Family: PolygonaceaeView DescriptionDichotomous Key

Habit: Annual to shrub [tree]. Stem: nodes swollen or not. Leaf: simple, basal or cauline, generally alternate; ocreae present or 0, generally scarious, persistent or not. Inflorescence: flower clusters in axillary to terminal cyme-, panicle-, raceme-, spike-, umbel- or head-like arrangements, entire inflorescence or main inflorescence branches generally subtended by bracts ("inflorescence bracts"); peduncles present or 0; flower clusters in Eriogoneae-Eriogonoideae subtended by involucre of >= 1 free or +- fused, sometimes awn-tipped bracts ("involucre bracts") or, in Polygonoideae and rarely in Eriogonoideae, not (if bracts completely fused, involucre "tubular"); pedicels in Eriogoneae each often subtended by 2 free, transparent, linear bractlets or in Polygonoideae all subtended by 2+ fused, membranous, wide bractlets. Flower: generally bisexual, small, 1--200 per node; perianth parts 2--6, generally in 2 whorls, free or basally fused, generally petal-like, often +- concave adaxially, often darker at midvein, often turning +- red or +- brown in age; stamens [1]3 or 6--9 in 2 whorls; ovary superior, 1-chambered, ovule 1, styles 1--3. Fruit: achenes, included in or exserted from perianth, generally 3-angled, ovoid or elliptic, generally glabrous.
Genera In Family: 48 genera, +- 1200 species: worldwide, especially northern temperate; some cultivated for food (Coccoloba, sea-grape; Fagopyrum, Rheum, Rumex) or ornamental (Antigonon, lovechain; Coccoloba; Muehlenbeckia; Persicaria; Polygonum), a few timbered (Coccoloba; Triplaris). Several (Emex; Fallopia; Persicaria; Polygonum; Rumex) are weeds. Note: Treatment of genera in Eriogonoideae based on monographic work of James L. Reveal. Involucre number throughout is number (1--many) per ultimate grouping, at tips of ultimate branches; flower number is per flower cluster or involucre, unless otherwise stated. Fagopyrum esculentum Moench not naturalized, considered an historical waif (or garden weed +- presently), therefore not treated.
eFlora Treatment Author: Mihai Costea, except as noted
Genus: BistortaView Description 

Species In Genus: 1 sp. Etymology: (Latin: bi-, twice, tortus, twisted, alluding to contorted rhizomes)

Bistorta bistortoides (Pursh) Small
Habit: Perennial herb, rhizomes contorted. Stem: (10)20--70 cm, branches 0. Leaf: generally basal; ocrea cylindric, 10--25(30) mm, brown, margins oblique, glabrous; petiole 10--30(50) mm; blade 4--30 cm, 1--4.8 cm wide, elliptic to lance-oblong or oblanceolate, base tapered to rounded, generally oblique, abaxially hairs 0 or +- white or +- brown, glaucous, adaxially hairs 0, margins entire, tip generally acute to acuminate; cauline leaves 2--4, petioled proximally, sessile distally, gradually reduced upward; blade elliptic or lanceolate to lance-linear. Inflorescence: terminal, spike-like, (10)20--40(50) mm, 10--25 mm wide, short-cylindric to ovoid; peduncle 1--10 cm; pedicel ascending or spreading, 2--10 mm; flowers 1--2. Flower: bisexual; perianth 4--5 mm, not enlarging, bell-shaped, glabrous, white or pale pink, parts 5, fused +- 1/5, oblong, tips obtuse to acute; stamens 5--8, exserted, anthers yellow, elliptic. Fruit: 3--4 mm, 1.2--2 mm wide, obovoid, light- or olive-brown, shiny, smooth. Chromosomes: 2n=24.
Ecology: Wet meadows, streambanks, alpine slopes; Elevation: 1500--3000 m. Bioregional Distribution: CA-FP (uncommon in coastal freshwater marshes, 0--20 m, NCo, n CCo), n SNE; Distribution Outside California: to Alaska, eastern North America. Flowering Time: Jul--Sep
Synonyms: Polygonum bistortoides Pursh
eFlora Treatment Author: Mihai Costea
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botanical illustration including Bistorta bistortoides


Citation for this treatment: Mihai Costea 2016. Bistorta bistortoides, in Jepson Flora Project (eds.) Jepson eFlora,, accessed on April 29, 2016.

Citation for the whole project: Jepson Flora Project (eds.) 2016. Jepson eFlora,, accessed on April 29, 2016.

Bistorta bistortoides
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© 2007 George W. Hartwell
Bistorta bistortoides
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© 2012 Barry Rice
Bistorta bistortoides
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© 2009 Barry Breckling
Bistorta bistortoides
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© 2009 Keir Morse
Bistorta bistortoides
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© 2012 Barry Rice
Bistorta bistortoides
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© 2008 Steve Matson

More photos of Bistorta bistortoides in CalPhotos

Geographic subdivisions for Bistorta bistortoides:
CA-FP (uncommon in coastal freshwater marshes, 0--20 m, NCo, n CCo), n SNE;
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.
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.