Home/Species/ California Jewelflower

Caulanthus californicus

(S. Wats.) Payson

California Jewelflower

G1Critically Imperiled Found in 16 roadless areas NatureServe Explorer →

G1Critically ImperiledGlobal Rank

Very highThreat Impact

Identity

Unique IDELEMENT_GLOBAL.2.153225

Element CodePDBRA31010

Record TypeSPECIES

ClassificationSpecies

Classification StatusStandard

Name CategoryVascular Plant

Endemicendemic to a single state or province

KingdomPlantae

PhylumAnthophyta

ClassDicotyledoneae

OrderCapparales

FamilyBrassicaceae

GenusCaulanthus

Synonyms

Stanfordia californicaS. Wats.Streptanthus californicus(S. Watson) Greene

Concept Reference

Kartesz, J.T. 1994. A synonymized checklist of the vascular flora of the United States, Canada, and Greenland. 2nd edition. 2 vols. Timber Press, Portland, OR.

Conservation Status

Rank Method Rank calculation - Biotics v2

Review Date2023-08-04

Change Date1988-03-08

Edition Date2023-08-04

Edition AuthorsBittman, R.L., rev. G. Davis (2000), rev. M. Fellows (2003), rev. A. Eberly (2023)

Threat ImpactVery high

Range Extent5000-20,000 square km (about 2000-8000 square miles)

Number of Occurrences21 - 80

Rank Reasons

Caulanthus californicus is a seed banking annual herb that occurs in the central valley of California in the western United States. There are approximately 37 occurrences but 24 haven't been revisited for over 20 years. This species has numerous threats including agriculture and urbanization that contribute to ongoing habitat degradation, loss, and fragmentation and caused historical declines, contributing to the known extirpation of 30 occurrences.

Range Extent Comments

Caulanthus californicus occurs in the western United States where it is endemic to California. It occurs in the San Joaquin and adjacent valleys. It was once fairly abundant in the appropriate habitat in Fresno, Kern, King, Santa Barbara, San Luis Obispo, and Tulare Counties but is only extant in Fresno, Kern, San Luis Obispo, and Santa Barbara Counties (CNDDB 2023). It is extirpated from Kings and Tulare Counties (CNDDB 2023).

Occurrences Comments

There are approximately 37 extant occurrences but 24 haven't been seen in over 20 years. An additional, 30 occurrences are presumably extirpated (CNDDB 2023).

Threat Impact Comments

This species is primarily threatened by habitat loss and fragmentation due to conversion of lands for agriculture or agricultural activities(including eutrophication), urban development, roads (and road maintenance), and energy development and exploration; habitat degradation due to grazing by livestock; and competition from non-native plants (USFWS 2013, 2020; CNDDB 2023). It may also be threatened by climate change influenced ecosystem shifts, and pesticide-kills of its pollinators (although the identity of the pollinators is unknown). The Giant Kangaroo Rat (another Federally Endangered Species) is thought to graze flowering/fruiting tops of plants prior to seed set, reducing reproductive success (USFWS 2013).

Ecology & Habitat

Habitat

This species grows in slightly alkaline, non-saline, sandy loam soils in non-native grassland, shrubland, and Juniper Woodland (Flora of North America Editorial Committee 2010, USFWS 2013, 2020).

Reproduction

This seed banking annual species remains dormant when conditions are unfavorable (USFWS 2020).

Terrestrial Habitats

Woodland - ConiferShrubland/chaparralGrassland/herbaceous

Other Nations (1)

United StatesN1

Province	Rank	Native
California	S1	Yes

Threat Assessments

Threat	Scope	Severity	Timing
1 - Residential & commercial development	Large (31-70%)	Extreme - serious	High (continuing)
1.1 - Housing & urban areas	Large (31-70%)	Extreme - serious	High (continuing)
2 - Agriculture & aquaculture	Large (31-70%)	Serious or 31-70% pop. decline	High (continuing)
2.1 - Annual & perennial non-timber crops	Large (31-70%)	Serious or 31-70% pop. decline	High (continuing)
2.3 - Livestock farming & ranching	Large (31-70%)	Moderate or 11-30% pop. decline	High (continuing)
3 - Energy production & mining	Small (1-10%)	Serious or 31-70% pop. decline	High (continuing)
3.1 - Oil & gas drilling	Small (1-10%)	Serious or 31-70% pop. decline	High (continuing)
4 - Transportation & service corridors	Large - restricted	Moderate or 11-30% pop. decline	High (continuing)
4.1 - Roads & railroads	Large - restricted	Moderate or 11-30% pop. decline	High (continuing)
8 - Invasive & other problematic species, genes & diseases	Large - restricted	Moderate or 11-30% pop. decline	High (continuing)
8.1 - Invasive non-native/alien species/diseases	Large - restricted	Moderate or 11-30% pop. decline	High (continuing)
8.2 - Problematic native species/diseases	Restricted (11-30%)	Moderate or 11-30% pop. decline	High (continuing)
9 - Pollution	Large - restricted	Unknown	High (continuing)
9.3 - Agricultural & forestry effluents	Large - restricted	Unknown	High (continuing)

Plant Characteristics

DurationANNUAL

Economic Value (Genus)No

Roadless Areas (16)

California (16)

Area	Forest	Acres
Big Rocks	Los Padres National Forest	11,866
Black Mountain	Los Padres National Forest	16,818
Cuyama	Los Padres National Forest	19,631
Cuyama	Los Padres National Forest	19,631
Fox Mountain	Los Padres National Forest	52,072
Fox Mountain	Los Padres National Forest	52,072
Garcia Mountain	Los Padres National Forest	7,850
Greenhorn Creek	Sequoia National Forest	28,226
La Panza	Los Padres National Forest	4,954
Los Machos Hills	Los Padres National Forest	11,112
Lpoor Canyon	Los Padres National Forest	13,762
Machesna Mountain	Los Padres National Forest	12,271
Mill Creek	Sequoia National Forest	27,643
Quatal	Los Padres National Forest	7,253
Sawmill - Badlands	Los Padres National Forest	51,362
Stanley Mountain	Los Padres National Forest	14,674

References (4)

Flora of North America Editorial Committee (FNA). 2010. Flora of North America north of Mexico. Vol. 7. Magnoliophyta: Salicaceae to Brassicaceae. Oxford University Press, New York. xxii + 797 pp.
Kartesz, J.T. 1994. A synonymized checklist of the vascular flora of the United States, Canada, and Greenland. 2nd edition. 2 vols. Timber Press, Portland, OR.
U.S. Fish and Wildlife Service (USFWS). 2013. <i>Caulanthus californicus</i> (California jewelflower) 5-Year Review: Summary and Evaluation. U.S. Fish and Wildlife Service, Sacramento Fish and Wildlife Office, Sacramento, California.
U.S. Fish and Wildlife Service (USFWS). 2020. 5-Year Review: California Jewelflower (<i>Caulanthus californicus</i>). U.S. Fish and Wildlife Service, Sacramento, California. 6 pp.

Caulanthus californicus

Habitat

Reproduction

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