Directory       News       Site Map       Home
         
    Jepson eFlora: Taxon page
Key to families | Table of families and genera

Previous taxon Indexes to all 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 |
Previous taxon

ASTERACEAE (Compositae) SUNFLOWER FAMILY

David J. Keil, except as noted

Annual to tree. Leaf: basal and/or cauline, alternate, opposite, rarely whorled, simple to 2+ × compound. Inflorescence: 1° inflorescence a head, resembling a flower, of several types (see below), 1–many in generally ± cyme-like cluster; each head generally with ± calyx-like involucre of 1–many series of phyllaries (involucral bracts); receptacle of head flat to conic or columnar, paleate (bearing paleae = receptacle bracts) or epaleate; flowers 1–many per head. Flower: bisexual, unisexual, or sterile, ± small, of several types (see below); calyx 0 or modified into ± persistent pappus of bristles, scales, and/or awns; corolla radial or bilateral (0), lobes generally (0)3–5; stamens 4–5, filaments generally free, generally fused to corolla at tube/throat junction, anthers generally fused into cylinder around style, anther base generally rounded or cordate (deeply sagittate or with tail-like appendages), tip (= flattened appendage) generally projecting beyond pollen sac; pistil 1, 2-carpeled, ovary inferior, 1-chambered, 1-seeded, placenta basal, style 1, tip generally ± 2-branched (except in some staminate disk flowers), branch tips truncate or generally bearing ± brush-like appendages; stigmas 2, generally on adaxial faces of style branches. Fruit: achene (also called a cypsela) (drupe in Chrysanthemoides), cylindric to ovoid, sometimes compressed, generally deciduous with pappus attached.
± 1500 genera, 23000 species: worldwide, many habitats. Flower and head types differ in form and sexual condition. A disk flower has a generally radial corolla, with a cylindric tube, expanded throat, and generally 5 lobes. Disk flowers are generally bisexual and fertile but occasionally staminate with reduced ovaries. Discoid heads comprise only disk flowers. A radiant head is a variant of a discoid head, with peripheral disk flower corollas expanded, often bilateral. A ray flower corolla is bilateral, generally with a slender tube and flattened petal-like ray (single lip composed of generally 3 lobes). Ray flowers are generally pistillate or sterile (occasionally lacking styles). Radiate heads have peripheral ray flowers and central disk flowers. Disciform heads superficially resemble discoid heads, with pistillate or sterile flowers that lack rays, together with or separate from disk flowers. A ligulate flower is bisexual, with a bilateral, generally ephemeral corolla and 5-lobed ligule. Liguliflorous heads comprise only ligulate flowers. See glossary p. 31 for illustrations of family characteristics. Echinops sphaerocephalus L., Gaillardia aristata Pursh, Gaillardia pulchella Foug., Hymenothrix loomisii S.F. Blake, Tagetes erecta L., Thelesperma megapotamicum (Spreng.) Kuntze are waifs. Melampodium perfoliatum Kunth, historic urban waif. Ageratum conyzoides L., Guizotia abyssinica (L. f.) Cass., Santolina chamaecyparisus L., orth. var. are rare or uncommon escapes from cultivation. Dyssodia papposa, Ismelia carinata (Schousb.) Sch. Bip. [Chrysanthemum carinatum Schousb.], Mantisalca salmantica (L.) Briq. & Cavill. are historical or extirpated waifs in California. Inula helenium L. not documented in California. Taxa of Aster in TJM (1993) treated here in Almutaster, Eucephalus, Eurybia, Ionactis, Oreostemma, Sericocarpus, Symphyotrichum; Chamomilla in Matricaria; Cnicus in Centaurea; Conyza in Erigeron and Laennecia; Dugaldia in Hymenoxys; Erechtites in Senecio; Hymenoclea in Ambrosia; Lembertia in Monolopia; Osteospermum ecklonis in Dimorphotheca; Picris echioides in Helminthotheca; Prionopsis in Grindelia; Raillardiopsis in Anisocarpus and Carlquistia; Schkuhria multiflora in Bahia; Trimorpha in Erigeron; Venidium in Arctotis; Whitneya in Arnica. Taxa of Arida in TJM2 treated here in Leucosyris. —Scientific Editors: David J. Keil, Bruce G. Baldwin.
Unabridged note: Largest family of vascular plants in California and of eudicots globally.

Key to Asteraceae

GUTIERREZIA SNAKEWEED, MATCHWEED

David J. Keil & Meredith A. Lane

Subshrub (in California), <= 1.5 m, appearing glabrous. Stem: 1–many from base, erect or ascending, branched distally, ± striate, gummy-resinous, minutely scabrous, yellow to tan or gray; older bark generally fibrous. Leaf: alternate, sometimes in axillary clusters, entire, gland-dotted, gummy-resinous, glabrous or minutely scabrous, dark gray-green. Inflorescence: heads radiate, generally many in ± open cyme-like clusters, 1 or in short-peduncled clusters at tips of inflorescence branches; involucre ± cylindric or narrowly to widely obconic; phyllaries graduated in 3–4 series, straw-colored, tips green; receptacle flat to conic, epaleate, minutely hairy. Ray flower: 1–13; corolla yellow, ray often inconspicuous. Disk flower: 1–13 (in California), bisexual or staminate; corolla yellow, club- or narrowly funnel-shaped, lobes short, recurved; style appendages lanceolate. Fruit: narrowly obconic, 5–8-veined, light tan, with ± white appressed hairs; pappus of 1–2 series of finely toothed, white or ± yellow scales generally 1/2 fruit length (in California) or much reduced.
28 species: western North America, South America. (Gutiérrez, surname of a noble Spanish family) TOXIC to livestock, fresh or dried in hay. [Nesom 2006 FNANM 20:88–94]
Unabridged references: [Lane 1985 Syst Bot 10:7–28]

Key to Gutierrezia

G. sarothrae (Pursh) Britton & Rusby MATCHWEED
NATIVE
Plant 1–6 dm. Stem: sprawling or upright, brown below, green or tan above. Leaf: single leaves lance-linear, clustered leaves thread-like. Inflorescence: heads 6–14-flowered, in clusters of 2–5 or fewer at 2° inflorescence tips, on peduncles < 1.5 mm or sometimes sessile; involucre generally <= 4.5 mm, <= 2.5 mm diam, cylindric or narrowly obconic; phyllaries 8–21 in 2–3 series. Ray flower: 2–8; corolla 3–5.4 mm. Disk flower: 2–9, bisexual; corolla 2.3–3.5 mm. Fruit: 0.9–1.6 mm.
2n=8,16,32. Grassland, desert, montane areas; 50–3050 m. South Coast, Western Transverse Ranges, Peninsular Ranges, Desert; to Washington, south-central Canada, central United States, northern Mexico. Intergrades with Gutierrezia californica in central and southern South Coast, Baja California. May–Oct [Online Interchange]

Previous taxon: Gutierrezia microcephala
Next taxon: Harmonia

Contact/Feedback

Name search

Citation for the whole project: Jepson Flora Project (eds.) 2013. Jepson eFlora, http://ucjeps.berkeley.edu/IJM.html, accessed on Sep 2 2014
Citation for this treatment: [Author of taxon treatment] 2013. Gutierrezia, in Jepson Flora Project (eds.) Jepson eFlora, http://ucjeps.berkeley.edu/cgi-bin/get_IJM.pl?tid=3149, accessed on Sep 2 2014

Copyright © 2014 Regents of the University of California
We encourage links to these pages, but the content may not be downloaded for reposting, repackaging, redistributing, or sale in any form, without written permission from The Jepson Herbarium.


click for enlargement Gutierrezia sarothrae
See CalPhotos for additional images
© 2007 Steve Matson

Geographic subdivisions indicated for the distribution of Gutierrezia sarothrae 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.
READ ABOUT YELLOW FLAGS
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

 

CCH collections by month

Duplicates counted once; synonyms included.
Species do not include records of infraspecific taxa.
Blue line denotes eFlora flowering time.