Jepson eFlora: Taxon page
Vascular Plants of California
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Juglans californica

Higher Taxonomy
Family: JuglandaceaeView DescriptionDichotomous Key
Habit: Shrub, tree; monoecious. Leaf: odd-(even-)1-pinnate, alternate, deciduous; stipules 0. Inflorescence: catkin, generally appearing before leaves, 1 or clustered; flowers generally 1 in bract axils. Staminate Inflorescence: pendent, elongate, many-flowered, on last year's twigs. Pistillate Inflorescence: erect; flowers 1--many, at tip of new twigs. Staminate Flower: calyx [0 or] lobes generally 4 [2, 6]; petals 0; stamens 3--40[50]; pistil 0 or vestigial. Pistillate Flower: calyx [0] or lobes 4; petals 0; stamens 0; ovary 1, inferior, chamber 1 above, generally 2 below, styles 2, plumose. Fruit: nut enclosed in husk or winged nutlets.
Genera In Family: 9 genera, > 60 species: northern temperate, subtropical mountains; some ornamental, cultivated for wood, nuts (Carya hickory, pecan; Juglans walnut). Note: In Carya, Juglans, husk included in fruit diam, even though derived from involucre, calyx, and therefore not technically part of fruit.
eFlora Treatment Author: Alan T. Whittemore
Scientific Editor: Thomas J. Rosatti.
Genus: JuglansView DescriptionDichotomous Key

Common Name: WALNUT
Stem: bark smooth to furrowed in age, gray to gray-brown; twig centers chambered; buds scaly. Pistillate Inflorescence: flowers 1--few; in fruit erect. Pistillate Flower: styles elongate. Fruit: 1--3 unwinged nuts per inflorescence; leathery husk enclosing, not separating from each nut, not splitting.
Etymology: (Latin: Jove's nut) Note: Wood used for interior finishing, furniture; source of nuts, dye. Juglans nigra L., occasionally planted, resembles Juglans hindsii but has leaflets uniformly pubescent abaxially, nuts deeply grooved, coarsely warty.
Juglans californica S. Watson
Stem: trunk 6--9 m. Leaf: petiole 2--5 cm; leaflets (9)11--15(17), 4--9.5 cm, generally narrow-elliptic to -lance-elliptic (less often lanceolate), +- serrate, rounded to acute, abaxial vein axils glabrous. Fruit: 2--3.5 cm diam, nut shell thick, shallowly grooved.
Ecology: Hillsides and canyons; Elevation: 30--900 m. Bioregional Distribution: SCoRO (Santa Lucia Range where cult), SW (exc ChI, SnBr). Flowering Time: Mar--May
Unabridged Synonyms: Juglans californica S. Watson var. californica
Jepson eFlora Author: Alan T. Whittemore
Index of California Plant Names (ICPN; linked via the Jepson Online Interchange)
Listed on CNPS Rare Plant Inventory

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Next taxon: Juglans hindsii

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Botanical illustration including Juglans californica

botanical illustration including Juglans californica


Citation for this treatment: Alan T. Whittemore 2012, Juglans californica, in Jepson Flora Project (eds.) Jepson eFlora,, accessed on February 01, 2023.

Citation for the whole project: Jepson Flora Project (eds.) 2023, Jepson eFlora,, accessed on February 01, 2023.

Juglans californica
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© 2003 Michael Charters
Juglans californica var. hindsi
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© 2007 George W. Hartwell
Juglans californica
click for enlargement
© 2019 Michael Charters
Juglans californica
click for enlargement
© 2003 Michael Charters
Juglans californica var. hindsi
click for enlargement
© 2007 George W. Hartwell
Juglans californica
click for enlargement
© 2003 Michael Charters

More photos of Juglans californica in CalPhotos

Geographic subdivisions for Juglans californica:
SCoRO (Santa Lucia Range where cult), SW (exc ChI, SnBr).
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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.
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

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).