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Vascular Plants of California
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Polygonum minimum

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
Scientific Editor: Thomas J. Rosatti, Bruce G. Baldwin.
Polygonum minimum S. Watson
Habit: Annual. Stem: prostrate to erect, 2--30 cm, wiry, often zigzagged, papillate-scabrous, red-brown, angled, branches from base or 0. Leaf: crowded distally or not; ocreae jointed to leaf, 1--5 mm, papillate-scabrous, proximally cylindric, distally entire to dentate-torn; petiole 0.1--3 mm; blade 6--27 mm, 3--8 mm wide, narrowly elliptic, elliptic, ovate, obovate, or +- round, margins flat, smooth, irregularly thickened or papillate-fine-dentate, tip mucronate. Inflorescence: pedicel included in bractlets, erect to spreading, 2--3 mm; flowers 1--3, near stem base, also crowded distally or not. Flower: 1/2-open or closed; perianth 1.8--2.5 mm, +- green, margin narrow, white or pink, tube 22--29% of length, lobes overlapped, oblong, hood-shaped, +- keeled, tip rounded, midvein thickened, unbranched; stamens 8. Fruit: included or exserted, 1.8--2.3 mm, elliptic to ovate, black, shiny, smooth.
Ecology: Meadows, open rocky or +- barren soil; Elevation: 700--3500 m. Bioregional Distribution: NW, CaR, SN; Distribution Outside California: western North America. Flowering Time: Jul--Sep
Synonyms: Polygonum torreyi S. Watson
Jepson eFlora Author: Mihai Costea
Reference: Costea 2005 Brittonia 57:1--27
Index of California Plant Names (ICPN; linked via the Jepson Online Interchange)

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Botanical illustration including Polygonum minimum

botanical illustration including Polygonum minimum

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Citation for this treatment: Mihai Costea 2012, Polygonum minimum, in Jepson Flora Project (eds.) Jepson eFlora,, accessed on October 03, 2023.

Citation for the whole project: Jepson Flora Project (eds.) 2023, Jepson eFlora,, accessed on October 03, 2023.

Polygonum minimum
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© 2009 Neal Kramer
Polygonum minimum
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© 2005 Keir Morse
Polygonum minimum
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© 2010 Barry Breckling
Polygonum minimum
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© 2011 Steve Matson
Polygonum minimum
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© 2008 Steve Matson
Polygonum minimum
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© 2015 Barry Breckling

More photos of Polygonum minimum in CalPhotos

Geographic subdivisions for Polygonum minimum:
1. You can change the display of the base map layer control box in the upper right-hand corner.
2. County and Jepson Region polygons can be turned off and on using the check boxes.
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).


Data provided by the participants of the  Consortium of California Herbaria.
View all CCH records
All markers link to CCH specimen records. The original determination is shown in the popup window.
Blue markers indicate specimens that map to one of the expected Jepson geographic subdivisions (see left map). Purple markers indicate specimens collected from a garden, greenhouse, or other non-wild location.
Yellow markers indicate records that may provide evidence for eFlora range revision or may have georeferencing or identification issues.

CCH collections by month

Duplicates counted once; synonyms included.
Species do not include records of infraspecific taxa, if there are more than 1 infraspecific taxon in CA.
Blue line denotes eFlora flowering time (fruiting time in some monocot genera).