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Nemacaulis denudata var. gracilis
SLENDER COTTONHEADS

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
Genus: NemacaulisView Description 

Common Name: COTTONHEADS

Species In Genus: 1 sp. Etymology: (Greek: thread stem, for slender stems)
eFlora Treatment Author: James L. Reveal & Thomas J. Rosatti
Species: Nemacaulis denudataView Description 

Habit: Annual, prostrate to erect, 0.4--2.5(4) dm, 2--8 dm diam, glabrous, glandular or hairy. Leaf: basal; blades 1--8 cm, 0.1--1.5 cm wide, linear to narrow; ocreae 0. Inflorescence: terminal, cyme-like; awns 0; peduncles 0 or erect, 0.5--3 mm; involucre bracts many, in several whorls, (1)2--4 mm, (0.3)0.5--2 mm wide, awns 0. Flower: 5--30, 0.8--1.5 mm, glabrous or minutely glandular; perianth white to rose, lobes 6, entire; stamens 3. Fruit: 1 mm, brown to deep maroon or black, obconic, glabrous; embryo curved.


Nemacaulis denudata var. gracilis Goodman & L.D. Benson
NATIVE
Habit: Plant 0.4--2.5(4) dm, 0.4--2 dm diam. Leaf: blades 1--7 cm, 0.1--0.6 cm wide. Inflorescence: branches light brown; involucre bracts 2--4 mm, 0.5--1 mm wide. Flower: 0.5--1.2 mm, generally obscured by hairs.
Ecology: Deserts; Elevation: 10--500 m. Bioregional Distribution: SW, DSon; Distribution Outside California: Arizona, northwestern Mexico. Flowering Time: Jan--May
eFlora Treatment Author: James L. Reveal & Thomas J. Rosatti
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Listed on CNPS Rare Plant Inventory

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botanical illustration including Nemacaulis denudata var. gracilis

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Citation for this treatment: James L. Reveal & Thomas J. Rosatti 2016. Nemacaulis denudata var. gracilis, in Jepson Flora Project (eds.) Jepson eFlora, http://ucjeps.berkeley.edu/cgi-bin/get_IJM.pl?tid=62269, accessed on May 24, 2016.

Citation for the whole project: Jepson Flora Project (eds.) 2016. Jepson eFlora, http://ucjeps.berkeley.edu/IJM.html, accessed on May 24, 2016.


Nemacaulis denudata var. gracilis
click for enlargement
© 2013 James M. Andre
Nemacaulis denudata var. gracilis
click for enlargement
© 2013 James M. Andre

More photos of Nemacaulis denudata var. gracilis in CalPhotos


Geographic subdivisions for Nemacaulis denudata var. gracilis:
SW, DSon;
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.
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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.