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Pterostegia drymarioides

Higher Taxonomy
Family: PolygonaceaeView DescriptionDichotomous Key

Common Name: BUCKWHEAT FAMILY
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: PterostegiaView Description 

Common Name: WOODLAND THREADSTEM

Species In Genus: 1 sp. Etymology: (Greek: wing covering, for winged bract)
eFlora Treatment Author: James L. Reveal & Thomas J. Rosatti

Pterostegia drymarioides Fisch. & C.A. Mey.
NATIVE
Habit: Annual, generally sprawling, 0.1--10(12) dm diam, hairy. Leaf: cauline, opposite; blades entire or generally lobed, wide, 0.3--2 cm, 0.5--2.5(3) cm wide, awns 0; ocreae 0. Inflorescence: terminal, cyme-like; peduncles 0; involucre bract erect, 2-winged, swollen on 1 side, veined, 1--1.5(3) mm, (1.5)2--3(3.5) mm wide, awns 0. Flower: 2--3, 0.9--1.2 mm, hairy; perianth pale yellow to pink or rose, lobes (5)6, entire; stamens 6. Fruit: 1.2--1.5 mm, obconic, winged, glabrous, generally brown; embryo straight. Chromosomes: n=14.
Ecology: Common. Sand or gravel; Elevation: < 1600 m. Bioregional Distribution: CA; Distribution Outside California: to southern Oregon, southwestern Utah, western Arizona, northwestern Mexico. Flowering Time: Mar--Jul
Synonyms: Pterostegia diphylla Nutt.; Pterostegia diphylla Nutt. var. biloba Nutt.; Pterostegia microphylla Nutt.
eFlora Treatment Author: James L. Reveal & Thomas J. Rosatti
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Citation for this treatment: James L. Reveal & Thomas J. Rosatti 2016. Pterostegia drymarioides, in Jepson Flora Project (eds.) Jepson eFlora, http://ucjeps.berkeley.edu/cgi-bin/get_IJM.pl?tid=40273, accessed on February 13, 2016.

Citation for the whole project: Jepson Flora Project (eds.) 2016. Jepson eFlora, http://ucjeps.berkeley.edu/IJM.html, accessed on February 13, 2016.


Pterostegia drymarioides
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© 2005 James M. Andre
Pterostegia drymarioides
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© 2012 Gary A. Monroe
Pterostegia drymarioides
click for enlargement
© 2004 James M. Andre
Pterostegia drymarioides
click for enlargement
© 2005 James M. Andre
Pterostegia drymarioides
click for enlargement
© 2004 James M. Andre
Pterostegia drymarioides
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© 2009 Keir Morse

More photos of Pterostegia drymarioides in CalPhotos


Geographic subdivisions for Pterostegia drymarioides:
CA;
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.