Lasthenia conjugens
status box


Illustration from Ferris (1960).

Illustration from Ferris (1960).

Photo taken at Fort Ord National Monument © 2011 Dylan Neubauer.

Photo taken at Fort Ord National Monument © 2011 Dylan Neubauer.

Cypselae of Contra Costa goldfields.

Cypselae of Contra Costa goldfields.

Photo taken at Fort Ord National Monument with Plagiobothrys chorisianus var. hickmanii © 2011 Dylan Neubauer.

Photo taken at Fort Ord National Monument with Plagiobothrys chorisianus var. hickmanii © 2011 Dylan Neubauer.

Photo © Dean W. Taylor.

Photo © Dean W. Taylor.

This fact sheet was prepared by Dylan M. Neubauer and Dean W. Taylor under award NA04N0S4200074 from the National Oceanic and Atmospheric Administration (NOAA), U.S. Department of Commerce (DOC). The statements, findings, conclusions, and recommendations are those of the authors and do not necessarily reflect the views of the NOAA or the DOC.

© Copyright 2006, Elkhorn Slough Coastal Training Program

Last updated: Nov 16, 2017 17:29

Common Names - Contra Costa goldfields

Family - Asteraceae (Sunflower Family)

State Status - none

Federal Status - federal endangered
(June 1997)


Vernal pools in areas with marine climatic influence; gen < 125 m.

Key Characteristics

Annual herb < 4 dm tall, stems simple or freely branched above, glabrous or +/- hairy; leaves < 8 cm long, linear, entire or pinnately lobed, glabrous; involucre 6–10 mm high, hemispheric to obconic, phyllaries 12–18, fused less than half their length (all other taxa in our region have phyllaries fused > 2/3ds their length); receptacle dome-shaped or obconic, densely hairy; corolla yellow, ray flowers 6–13(18), the rays 5–10 mm, disk flowers many, style tips triangular; cypselae glabrous, epappose (Chan and Ornduff 2013).

Flowering Period

March to June

Reference Population

Fort Ord National Monument (Monterey County)

Global Distribution

Endemic to California in Santa Barbara (presumably extirpated), Monterey, Santa Clara (presumably extirpated), Alameda, Contra Costa, Solano, Marin, Napa, Sonoma, and Mendocino (presumably extirpated) counties (CNPS 2010).


Critically endangered by loss of vernal pool habitat throughout its historical range, experimental restoration has occurred at several sites in Solano and Mendocino counties. The four distinct populations in our region (at Fort Ord National Monument) appear stable, though in the recent past one of these populations has been degraded by wild-pig rooting. These four populations virtually split the historical distribution as documented by herbarium specimens (Ornduff 1966). This distribution suggests that this species may have occurred in vernal pools in the Salinas Valley, an ecosystem now virtually extinct.


California Natural Diversity Database (CNDDB). 2015. California Department of Fish and Wildlife RareFind 5. [accessed 19 January 2015]

Chan, R. and R. Ornduff. 2013. Lasthenia conjugens, in Jepson Flora Project (eds.) Jepson eFlora. [accessed 19 January 2015].

CNPS, Rare Plant Program. 2010. Lasthenia conjugens, in Inventory of Rare and Endangered Plants (online edition, v8-02). California Native Plant Society, Sacramento, CA. [accessed 19 January 2015].

Ferris R. S. 1960. Illustrated flora of the Pacific States, Vol. IV. Stanford University Press, Stanford, CA.

Ornduff, R. 1966. A biosystematic survey of the goldfield genus Lasthenia. University of California Publications in Botany 40:1–92.

U.S. Fish & Wildlife Service (USFWS). 2005. Recovery plan for vernal pool ecosystems of California and southern Oregon. Region 1. Portland Oregon [accessed 19 January 2015].

U.S. Fish & Wildlife Service (USFWS). 2013. Lasthenia conjugens (Contra Costa Goldfields) 5-year review: summary and evaluation. Sacramento Fish and Wildlife Office, Sacramento, CA. [accessed 19 January 2015].


Bruce Delgado (May 2015)

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