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Vascular Plants of California
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Gamochaeta ustulata

Higher Taxonomy
Family: Asteraceae (Compositae)View DescriptionDichotomous Key
Habit: 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 (involucre 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.
Genera In Family: +- 1500 genera, 23000 species: worldwide, many habitats. Note: 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, Doellingeria, Eurybia, Ionactis, Oreostemma, Sericocarpus, Symphyotrichum; Chamomilla in Matricaria; Bahia in Hymenothrix; 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 Picradeniopsis; Trimorpha in Erigeron; Venidium in Arctotis; Viguiera in Aldama and Bahiopsis; Whitneya in Arnica. Amauriopsis in TJM2 (2012) treated here in Hymenothrix; Arida in Leucosyris; Bahia in Picradeniopsis; Eucephalus in Doellingeria.
Unabridged Note: Largest family of vascular plants in California and of eudicots globally.
eFlora Treatment Author: David J. Keil, except as noted
Scientific Editor: David J. Keil, Bruce G. Baldwin.
Genus: GamochaetaView DescriptionDichotomous Key

Common Name: CUDWEED
Habit: Annual to short-lived perennial herb; taprooted or fibrous-rooted. Stem: erect to +- ascending. Leaf: basal and cauline, +- sessile, linear to oblanceolate or spoon-shaped, entire, base tapered to +- cordate, generally +- densely tomentose. Inflorescence: heads disciform, generally in tight groups in generally spike- or panicle-like clusters, reduced to terminal cluster in small plants; involucre cylindric to +- urn-shaped, +- bell-shaped when pressed; phyllaries graduated in 3--7 series, bases stiff-papery to scarious, margins and tips transparent-membranous, often shiny, generally +- brown to straw-colored; receptacle flat, concave in fruit, smooth, epaleate. Pistillate Flower: pistillate 50--130; corolla narrowly tubular, yellow or distally +- purple to purple- to yellow-brown. Disk Flower: 2--7; corolla yellow or distally +- purple or purple- to yellow-brown; anther tip triangular; style tips truncate, hair-tufted. Fruit: oblong, slightly flattened, faces papillate; pappus bristles in 1 series, basally fused, deciduous in ring.
Etymology: (Greek: united hair, for pappus bristles)
eFlora Treatment Author: Guy L. Nesom & Thomas J. Rosatti
Reference: Nesom 2006 FNANM 19:431--438; Strother et al. 2012 Phytoneuron 2012-52:1--5
Gamochaeta ustulata (Nutt.) Holub
Habit: Annual to biennial or short-lived perennial herb, fibrous-rooted. Stem: erect to ascending, 10--40 cm, generally decumbent-ascending and stolon-like, white, densely felty-tomentose. Leaf: basal and cauline, basal generally withering before flower, 2--5 cm, 6--12(35) mm wide, spoon-shaped to oblanceolate, faces contrasting in color, adaxially +- sparsely cobwebby-tomentose, abaxially white, felty-tomentose. Inflorescence: head clusters 1--6(8+) cm, 12--18 mm wide (pressed), +- cylindric, in age generally continuous, if interrupted then only basally; involucre 4.5--5 mm, urn-shaped, base embedded in woolly hairs, often sparsely cobwebby on proximal 1/5--1/2; phyllaries in 4--6 series, outer widely ovate-triangular, +- 1/2 × inner, acute to acuminate, brown or +- green-brown, mid phyllaries +- keeled near tip, inner oblong, flattened, rounded to obtuse, abruptly pointed, generally dark brown, sometimes proximally +- purple. Pistillate Flower: corolla generally +- yellow, sometimes +- purple-tipped. Disk Flower: (3)4--6; corolla generally +- yellow, sometimes +- purple-tipped. Fruit: 0.7--0.8 mm.
Ecology: Dunes, bluffs, fields, disturbed sites; Elevation: < 650(1050) m. Bioregional Distribution: NW, c SNF, SnJV, w CW, SCoRO, SCo, ChI, PR; Distribution Outside California: to British Columbia. Flowering Time: Apr--Jul
Unabridged Synonyms: Gnaphalium purpureum L., misappl.
Jepson eFlora Author: Guy L. Nesom & Thomas J. Rosatti
Reference: Nesom 2006 FNANM 19:431--438; Strother et al. 2012 Phytoneuron 2012-52:1--5
Index of California Plant Names (ICPN; linked via the Jepson Online Interchange)

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Citation for this treatment: Guy L. Nesom & Thomas J. Rosatti 2013, Gamochaeta ustulata, in Jepson Flora Project (eds.) Jepson eFlora, Revision 1,, accessed on June 16, 2024.

Citation for the whole project: Jepson Flora Project (eds.) 2024, Jepson eFlora,, accessed on June 16, 2024.

Gamochaeta ustulata
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©2008 Neal Kramer
Gamochaeta ustulata
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©2016 Neal Kramer
Gamochaeta ustulata
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©2007 Neal Kramer
Gamochaeta ustulata
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©2016 Neal Kramer
Gamochaeta ustulata
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©2013 Vernon Smith

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Geographic subdivisions for Gamochaeta ustulata:
NW, c SNF, SnJV, w CW, SCoRO, SCo, ChI, PR
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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).


Data provided by the participants of the  Consortium of California Herbaria.
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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).