Jepson eFlora: Taxon page
Vascular Plants of California
Key to families | Table of families and genera
Previous taxon Index to accepted names and synonyms:
| A | B | C | D | E | F | G | H | I | J | K | L | M |
| N | O | P | Q | R | S | T | U | V | W | X | Y | Z |
Next taxon

Sidotheca emarginata

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.
Genus: SidothecaView DescriptionDichotomous Key

Habit: Annual, generally spreading, glabrous or glandular. Leaf: basal, linear to narrow, hairy, glandular, awns 0; ocreae 0. Inflorescence: terminal, cyme-like; peduncle erect to spreading; involucre 1, tubular, teeth 5(6), awned. Flower: 2--5(10), hairy, glandular; perianth white to rose or green-yellow to red, lobes 6, 3-lobed to fringed; stamens 9. Fruit: brown, obconic, glabrous; embryo curved.
Species In Genus: 3 species: western North America. Etymology: (Greek: star case, for involucre)
eFlora Treatment Author: James L. Reveal & Thomas J. Rosatti
Sidotheca emarginata (H.M. Hall) Reveal
Habit: Plant 0.3--3 dm, 0.3--5 dm diam. Leaf: blades 1.5--7.5 cm, 0.4--1.5 cm wide. Inflorescence: bract awns 1--2 mm; peduncles erect, 0.5--3 cm, glandular; involucre 4--8 mm, 9--12 mm wide, glabrous, margin white, teeth 5, awns 1--1.5 mm, +- red. Flower: 3--6, (2)3--4.5(5) mm; perianth white to pink, lobes with 3--5 fringed linear lobes. Fruit: 1.8--2 mm.
Ecology: Gravel; Elevation: 1200--2500 m. Bioregional Distribution: e PR (SnJt, Santa Rosa Mtns, Riverside Co.). Flowering Time: Feb--Aug
Synonyms: Eriogonum emarginatum (H.M. Hall) S. Stokes; Oxytheca emarginata H.M. Hall
Jepson eFlora Author: James L. Reveal & Thomas J. Rosatti
Index of California Plant Names (ICPN; linked via the Jepson Online Interchange)
Listed on CNPS Rare Plant Inventory

Previous taxon: Sidotheca caryophylloides
Next taxon: Sidotheca trilobata

Name Search

Botanical illustration including Sidotheca emarginata

botanical illustration including Sidotheca emarginata


Citation for this treatment: James L. Reveal & Thomas J. Rosatti 2012, Sidotheca emarginata, in Jepson Flora Project (eds.) Jepson eFlora,, accessed on May 15, 2021.

Citation for the whole project: Jepson Flora Project (eds.) 2021, Jepson eFlora,, accessed on May 15, 2021.

Sidotheca emarginata
click for enlargement
© 2017 Keir Morse
Sidotheca emarginata
click for enlargement
© 2009 Neal Kramer
Sidotheca emarginata
click for enlargement
© 2014 Keir Morse
Sidotheca emarginata
click for enlargement
© 2014 Keir Morse
Sidotheca emarginata
click for enlargement
© 2017 Keir Morse
Sidotheca emarginata
click for enlargement
© 2019 Aaron Schusteff

More photos of Sidotheca emarginata in CalPhotos

Geographic subdivisions for Sidotheca emarginata:
e PR (SnJt, Santa Rosa Mtns, Riverside Co.).
1. You can change the display of the base map and layers by clicking on the layer control box in the upper right-hand corner.
2. California county polygons can be turned off and on in the layer control box.
3. Filling of Jepson subdivision polygons can be turned off and on in the layer control box.
4. Moving the cursor over any numbered cluster will show the range boundary of the included specimens (with a blue polygon).
5. Marker clustering can be turned off by clicking this link:      Marker Clustering OFF
WARNING: Turning this off might cause maps with large numbers of specimens to load slowly.
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).


View elevation by latitude chart

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).