Taxon Details

Juglans californica

Southern California black walnut

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Taxon Summary:

Juglans californica, commonly known as Southern California black walnut, is a perennial deciduous tree in the Juglandaceae that is found only in California. It occurs within Chaparral, Cismontane woodland, Coastal scrub, and Riparian woodland, growing at elevations from 50 to 900 meters. Juglans californica is ranked 4.2, Plants of Limited Distribution, A Watch List; Moderately threatened in California.

Classification

Scientific Name: Juglans californica Wats.
Common Name: Southern California black walnut
Family:	Juglandaceae
Element Code:	PDJUG02020
USDA Plants Symbol:	JUCA
Synonyms/Other Names: Juglans californica Wats. var. californica
Name Status:	JEF, FNA, POWO, IPNI, Tropicos

Conservation Status

CA Rare Plant Rank:	4.2
Fed List:	None
State List:	None
Global Rank:	G4
State Rank:	S4
Other Status:	IUCN_NT; SB_CalBG/RSABG; SB_USDA
CRPR Changes:
Add Date:	1994-01-01
Date Edited:	2022-01-05

Ecology and Life History

Lifeform: perennial deciduous tree

Blooming Period: Mar-Aug

Elevation:
50 - 900 meters
165 - 2955 feet

General Habitats:

Chaparral
Cismontane woodland
Coastal scrub
Riparian woodland

Microhabitat Details: alluvial

Microhabitat:

Notes

Notes: Walnut forest is a much fragmented, rare, and declining vegetation community. Threatened by urbanization, grazing, non-native plants, and possibly by lack of natural reproduction. Possibly threatened by hybridization with horticultural varieties of walnut. A synonym of J. californica var. californica in The Jepson Manual. See Proceedings of the American Academy of Arts and Sciences 10:349 (1875) for original description, and Southern California Botanists Special Publication No. 3, pp. 42-54 (1990) for additional information.
Threats:
Taxonomy:

Threat List Data from the CNDDB

THREAT LIST:
Threat List Total:	0
	Total EOs	% of EOs
EOs with Threat Listed:	0	0 %

Occurrence Data from the CNDDB

Element Occurrence Ranks:
Total Occurrences:					0
A	B	C	D	X	U
0	0	0	0	0	0

Occurrence Status:
Historical >20 Years	0
Recent <=20 Years	0

Presence:
Presumed Extant	0
Possibly Extirpated	0
Presumed Extirpated	0

Location

California Endemic:

California Island:

States: Name (Code)
California (CA)

California Counties and Islands: Name (Code)
Fresno (FRE), Kern (KRN), Los Angeles (LAX), Orange (ORA), Riverside (RIV), San Bernardino (SBD), San Diego (SDG), Santa Barbara (SBA), Santa Clara (SCL), Ventura (VEN)

Quads: Name (Quad Code)
Acton (3411842), Alamo Mountain (3411868), Alberhill (3311764), Alpine (3211677), Anaheim (3311778), Azusa (3411728), Bachelor Mtn. (3311751), Bald Mountain (3411978), Baldwin Park (3411718), Beaumont (3311688), Beverly Hills (3411814), Black Mtn. (3411867), Black Star Canyon (3311776), Blackburn Canyon (3311667), Bonsall (3311732), Borrego Palm Canyon (3311634), Burbank (3411823), Cabazon (3311687), Cajon (3411734), Calabasas (3411826), Camarillo (3411921), Canada Gobernadora (3311755), Canoga Park (3411825), Carpinteria (3411945), Casmalia (3412075), Cobblestone Mtn. (3411857), Condor Peak (3411832), Corona North (3311785), Corona South (3311775), Crystal Lake (3411737), Cucamonga Peak (3411725), Del Mar (3211782), Devils Heart Peak (3411858), Devore (3411724), Dulzura (3211667), Eagle Rest Peak (3411982), Earthquake Valley (3311614), El Cajon (3211678), El Cajon Mtn. (3211687), El Casco (3311781), El Monte (3411811), El Toro (3311766), Encinitas (3311713), Fallbrook (3311743), Fillmore (3411848), Fontana (3411714), Forest Falls (3411618), Glendora (3411727), Goleta (3411947), Green Valley (3411854), Guasti (3411715), Hollywood (3411813), Jamul Mountains (3211668), Julian (3311615), La Habra (3311788), Laguna Beach (3311757), Lake Elsinore (3311763), Lake Mathews (3311774), Lion Canyon (3411952), Lompoc Hills (3412054), Los Alamos (3412063), Los Angeles (3411812), Malibu Beach (3411816), Matilija (3411943), Mint Canyon (3411844), Moorpark (3411838), Mount San Antonio (3411736), Mt. Baldy (3411726), Mt. Wilson (3411821), Murrieta (3311752), Newbury Park (3411828), Newhall (3411845), Oat Mountain (3411835), Ojai (3411942), Old Man Mountain (3411954), Ontario (3411716), Orange (3311777), Orcutt (3412074), Pala (3311731), Pasadena (3411822), Piru (3411847), Pitas Point (3411934), Point Conception (3412044), Point Dume (3411817), Point Mugu (3411911), Prado Dam (3311786), Rancho Nuevo Creek (3411964), Rancho Santa Fe (3311712), Redlands (3411712), Riverside East (3311783), Riverside West (3311784), Rodriquez Mtn. (3311628), Romoland (3311762), San Bernardino North (3411723), San Bernardino South (3411713), San Dimas (3411717), San Fernando (3411834), San Pasqual (3311618), Santa Barbara (3411946), Santa Paula (3411931), Santa Paula Peak (3411941), Santa Rosa Hills (3412053), Santa Susana (3411836), Santa Ynez (3412051), Santiago Peak (3311765), Saticoy (3411932), Silverwood Lake (3411733), Simi (3411837), Sitton Peak (3311754), Solvang (3412052), Sunland (3411833), Sunnymead (3311782), Telegraph Peak (3411735), Temecula (3311742), Thousand Oaks (3411827), Topanga (3411815), Torrance (3311873), Tranquillon Mtn. (3412055), Triunfo Pass (3411818), Tubb Canyon (3311624), Val Verde (3411846), Valyermo (3411747), Van Nuys (3411824), Ventura (3411933), Viejas Mountain (3211676), Warm Springs Mountain (3411855), Waterman Mtn. (3411738), Wheeler Springs (3411953), Whitaker Peak (3411856), White Ledge Peak (3411944), Whittier (3311881), Wildomar (3311753), Winchester (3311761), Yorba Linda (3311787), Yucaipa (3411711)

Notes:

Definitions of codes following a county and/or quad:
*		Presumed extirpated
(?)		Occurrence confirmed, but possibly extirpated
Quad and county data is imported from the CNDDB. Species may be present in other areas where conditions are favorable. These data should NOT be substituted for pre-project review or for on-site surveys.

Regional Map

Map

Presumed Extant

Click on quad for name. Hold Shift Key to use mouse scroll wheel

CNPS Rare Plant Inventory