Jepson eFlora: Taxon page
Vascular Plants of California
Key to families | Table of families and genera
Previous taxon Index to 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 |
Next taxon

Ceanothus thyrsiflorus var. thyrsiflorus


Higher Taxonomy
Family: RhamnaceaeView DescriptionDichotomous Key
Habit: [Perennial herb] shrub, tree, generally erect, often thorny. Leaf: simple, generally alternate, often clustered on short-shoots; stipules generally present, occasionally modified into spines; generally petioled; blade pinnate-veined or 1--5-ribbed from base. Inflorescence: cyme, panicle, umbel, or flowers 1 or clustered in axils or on short-shoots. Flower: generally bisexual, radial; hypanthium subtending, surrounding, or partly fused to ovary; sepals 4--5; petals 0, 4--5, generally clawed; stamens 0, 4--5, alternate sepals, attached to hypanthium top, each generally fitting into a petal concavity; disk (0 or) between stamens, ovary, thin to fleshy, entire or lobed, free from ovary, adherent or fused to hypanthium; ovary superior or +- inferior, chambers [1]2--4, 1--2-ovuled, style 1, stigma entire or 2--3-lobed. Fruit: capsule, drupe.
Genera In Family: 50--52 genera, 950 species: especially tropics, subtropics some cultivated (Ceanothus; Frangula; Rhamnus; Ziziphus).
eFlora Treatment Author: John O. Sawyer, Jr., except as noted
Scientific Editor: Steve Boyd, Thomas J. Rosatti.
Genus: CeanothusView DescriptionDichotomous Key

Habit: Shrub, tree-like or not, generally erect or mat- to mound-like. Stem: branches generally arranged like leaves; twigs thorn-like or not, generally not angled. Leaf: alternate or opposite, some clustered on short-shoots or not, deciduous or evergreen; stipules scale-like, thin, deciduous, or knob-like, corky, thick, base persistent; blade flat or wavy, tip generally acute to obtuse, margin thick (i.e., thicker than adjacent blade) or not, rolled under or not, wavy or not, entire or gland- or sharp-toothed, glands generally dark, teeth pale, alternate blade 1--3-ribbed from base, generally thin, opposite blade 1-ribbed from base, thick, firm. Inflorescence: umbel-, raceme-, or panicle-like aggregations of few-flowered clusters, axillary or terminal; pedicels white to deep blue or pink. Flower: conspicuous, generally < 5 mm; hypanthium surrounding fleshy disk below ovary base, in fruit thick, not splitting; sepals generally 5, lance-deltate, incurved, colored like petals, persistent; petals generally 5, blade hood-like, white to deep blue or pink; stamens generally 5, opposite petals; ovary 1/2-inferior, 3-lobed, chambers 3, each 1-ovuled, styles 3. Fruit: capsule, +- spheric, generally +- 3-lobed, generally smooth, 3-ridged or not, horned or not. Seed: 3, 2--5 mm.
Etymology: (Greek: thorny pl) Note: Hybrids possibly common (named hybrids not recognized here), discussed in Fross & Wilken; possible hybrid forms do not key easily.
eFlora Treatment Author: Dylan O. Burge & Dieter H. Wilken
Reference: Fross & Wilken 2006 Ceanothus. Timber Press; Burge et al. 2015 Syst Bot 40:950--961.
Species: Ceanothus thyrsiflorusView Description 

Habit: Plant mat-like to erect, occasionally tree-like, +- open, < 6 m. Stem: spreading to erect; twigs flexible, not thorn-like, angled distally, ridged, green. Leaf: alternate, evergreen; stipules scale-like; petiole 3--9 mm; blade 10--39 mm, 5--20 mm wide, oblong-ovate, ovate, or widely elliptic, +- firm, adaxially dark green, glabrous, abaxially paler, glabrous to puberulent between veins or not, veins +- raised, sparsely puberulent, tip obtuse to rounded, margin +- gland-toothed. Inflorescence: generally raceme- or panicle-like, 1.5--7 cm. Flower: light to deep blue (white). Fruit: 2.5--4 mm wide, sticky; horns 0.

Ceanothus thyrsiflorus Eschsch. var. thyrsiflorus
Stem: twigs +- glabrous. Leaf: blade oblong-ovate to elliptic, margin not to partly rolled under. Chromosomes: 2n=24.
Ecology: Bluffs, slopes, canyons, chaparral, coastal scrub, closed-cone-pine forest; Elevation: < 800 m. Bioregional Distribution: NCo, KR, s NCoRI, NCoRO, CCo, SnFrB, SCoRO; Distribution Outside California: southwestern Oregon, northern Baja California. Flowering Time: Mar--Jun
Synonyms: Ceanothus thyrsiflorus var. chandleri Jeps.; Ceanothus thyrsiflorus var. repens McMinn
Jepson eFlora Author: Dylan O. Burge & Dieter H. Wilken
Reference: Fross & Wilken 2006 Ceanothus. Timber Press; Burge et al. 2015 Syst Bot 40:950--961.
Index of California Plant Names (ICPN; linked via the Jepson Online Interchange)

Previous taxon: Ceanothus thyrsiflorus var. obispoensis
Next taxon: Ceanothus tomentosus

Botanical illustration including Ceanothus thyrsiflorus var. thyrsiflorusbotanical illustration including Ceanothus thyrsiflorus var. thyrsiflorus

Please use this Google Form for Contact/Feedback

Citation for this treatment: Dylan O. Burge & Dieter H. Wilken 2020, Ceanothus thyrsiflorus var. thyrsiflorus, in Jepson Flora Project (eds.) Jepson eFlora, Revision 8,, accessed on July 15, 2024.

Citation for the whole project: Jepson Flora Project (eds.) 2024, Jepson eFlora,, accessed on July 15, 2024.

Ceanothus thyrsiflorus  
var. thyrsiflorus
click for image enlargement
©2006 Steve Matson
Ceanothus thyrsiflorus  
var. thyrsiflorus
click for image enlargement
©2016 Neal Kramer
Ceanothus thyrsiflorus  
var. thyrsiflorus
click for image enlargement
©2013 Neal Kramer
Ceanothus thyrsiflorus  
var. thyrsiflorus
click for image enlargement
©2006 Steve Matson
Ceanothus thyrsiflorus  
var. thyrsiflorus
click for image enlargement
©2006 Steve Matson

More photos of Ceanothus thyrsiflorus var. thyrsiflorus
in CalPhotos

Geographic subdivisions for Ceanothus thyrsiflorus var. thyrsiflorus:
NCo, KR, s NCoRI, NCoRO, CCo, SnFrB, SCoRO
1. You can change the display of the base map layer control box in the upper right-hand corner.
2. County and Jepson Region polygons can be turned off and on using the check boxes.
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 occurrence).


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

View all CCH records
All markers link to CCH specimen records. The original determination is shown in the popup window.
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 Flowering-Fruiting Monthly Counts

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).