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Eriogonum microthecum var. simpsonii

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: EriogonumView DescriptionDichotomous Key

Habit: Annual to shrub, matted or not. Stem: prostrate to erect, occasionally 0, glabrous or hairy, occasionally glandular. Leaf: basal, sheathing (on stem above basal, beneath other, +- non-sheathing cauline), or cauline, alternate, opposite, or whorled; blades linear to +- round, generally longer than wide, margins flat, wavy, or rolled under; ocreae 0. Inflorescence: variable, glabrous or hairy, occasionally glandular; peduncles 0 or erect to reflexed (pointed down); involucres 1 or in clusters, tubular, glabrous or hairy, teeth generally 4--10, awns 0. Flower: (2)6--100(200), with a stalk-like base ("flower stipe" or "stipe") or not; perianth generally white to red or yellow, glabrous or hairy, occasionally glandular, lobes 6, generally entire; stamens 9. Fruit: generally brown or black, generally obconic, glabrous or hairy; embryo curved or straight.
Species In Genus: +- 250 species: temperate North America. Etymology: (Greek: woolly knees, for hairy nodes of 1st sp. named) Note: One of largest genera in California; stem in descriptions refers to the main stem(s), not branches of inflorescence. A perennial herb allied to Eriogonum austrinum (S. Stokes) Reveal and Eriogonum moranii Reveal of east-central Baja California, with spreading (rather than reflexed or erect) involucres on peduncles < 2 mm, occurring in DMtns (Bristol, Granite mountains), has been known for nearly 25 years yet remains undescribed. Eriogonum puberulum moved to Johanneshowellia.
eFlora Treatment Author: James L. Reveal & Thomas J. Rosatti

Eriogonum microthecum var. simpsonii (Benth.) Reveal
Habit: Subshrub or shrub, (1)2--15 dm, 4--16 dm diam. Stem: 0.2--0.7 dm, generally tomentose, sometimes hairy (or glabrous). Leaf: blades 0.5--1.8(2.5) cm, 0.1--0.2 cm wide, tomentose abaxially, generally hairy adaxially, margins generally rolled under. Inflorescence: (1.5)2--4(6) cm; branches tomentose to hairy (or glabrous); involucres 2--3 mm, generally tomentose to hairy. Flower: 2--3 mm; perianth white to pink or rose. Fruit: 2--3 mm.
Ecology: Common. Gravel to rocks; Elevation: 1400--2300 m. Bioregional Distribution: s SNE, DMoj; Distribution Outside California: to Colorado, northwestern New Mexico; disjunct in northeastern Idaho and southwestern Montana. Flowering Time: Jun--Oct
Synonyms: Eriogonum effusum Nutt. var. foliosum Torr.; Eriogonum effusum subsp. nelsonii (L.O. Williams) S. Stokes; Eriogonum effusum subsp. simpsonii (Benth.) S. Stokes; Eriogonum friscanum M.E. Jones; Eriogonum macdougalii (Gand.) Prain; Eriogonum microthecum var. foliosum (Torr.) Reveal; Eriogonum microthecum var. friscanum (M.E. Jones) S. Stokes; Eriogonum microthecum subsp. intermedium S. Stokes; Eriogonum microthecum subsp. macdougalii Gand.; Eriogonum microthecum var. macdougalii (Gand.) S. Stokes; Eriogonum microthecum subsp. rigidum (Eastw.) S. Stokes; Eriogonum microthecum var. rigidum Eastw.; Eriogonum nelsonii L.O. Williams; Eriogonum simpsonii Benth.;
eFlora Treatment Author: James L. Reveal & Thomas J. Rosatti
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Citation for this treatment: James L. Reveal & Thomas J. Rosatti 2012, Eriogonum microthecum var. simpsonii, in Jepson Flora Project (eds.) Jepson eFlora,, accessed on February 24, 2018.

Citation for the whole project: Jepson Flora Project (eds.) 2018, Jepson eFlora,, accessed on February 24, 2018.

Eriogonum microthecum var. simpsonii
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© 2005 James M. Andre
Eriogonum microthecum var. simpsonii
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© 2016 Keir Morse
Eriogonum microthecum var. simpsonii
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© 2008 Aaron Schusteff
Eriogonum microthecum var. simpsonii
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© 2010 Steve Matson
Eriogonum microthecum var. simpsonii
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© 1991 Gary A. Monroe
Eriogonum microthecum var. simpsonii
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© 2016 Keir Morse

More photos of Eriogonum microthecum var. simpsonii in CalPhotos

Geographic subdivisions for Eriogonum microthecum var. simpsonii:
s SNE, DMoj;
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.
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, if there are more than 1 infraspecific taxon in CA.
Blue line denotes eFlora flowering time.