Endemic to California . Reported from San Diego County, Santa Rosa Island, Santa Cruz County, and Monterey County .
Known Populations in San Diego County
Within the MSPA, two extant occurrences in MUs 6 and 7 . In MU6, found in east Del Mar at Overlook Park and in MU7, found at Crest Canyon.
Occurs below 60m elevation in sandy areas and openings in maritime chaparral, coastal dunes, and coastal scrub . Reported in eroded dunes away from the existing beachline, and sandy locales in chaparral openings . Locations at Torrey Pines State Park map to Corralitos loamy sand and locations at Camp Pendleton map to Olivenhain cobbly loam.
Taxonomy and genetics
Originally classified in more widespread and inland species, Erysimum capitatum ssp. capitatum. More recently combined with coastal Santa Cruz and island populations into E. ammophilum .
Life history demography
Yellow-flowered perennial, blooms February-June . Elsewhere reported as biennial .
Pollination seed dispersal
Close to extirpation in San Diego County .Threatened by development . As with other coastal strand and dune plants, likely to have been adversely affected by coastal development, human disturbance and competition with non-native invasive plants.
Coast wallflower sources
 1. Calflora 2012. Calflora: Information on California plants for education, research and conservation, based on data contributed by dozens of public and private institutions and individuals, including the Consortium of Calif. Herbaria. [Calflora]. 2012. Berkeley, California: The Calflora Database a non-profit organization]. Available: http://www.calflora.org/ [Accessed: Aug 29, 2012].2. Reiser, C.H. 1994. Rare plants of San Diego County. Aquafir Press, Imperial Beach, CA. Available online: http://sandiego.sierraclub.org/rareplants/3. MSP-MOM. 2014. Management Strategic Plan Master Occurrence Matrix. http://sdmmp.com/reports_and_products/Reports_Products_MainPage.aspx4. CNPS, Rare Plant Program. 2014. Inventory of Rare and Endangered Plants [online edition, v8-02]. California Native Plant Society, Sacramento, CA. Website http://www.rareplants.cnps.org accessed 16 June 2014].5. Baldwin, B.G., D.H. Goldman, D.J. Keil, R. Patterson and T.J. Rosatti [Eds.]. 2012. The Jepson Manual: Vascular Plants of California, Second Edition, Thoroughly Revised and Expanded. University of California Press, Berkeley, California. 1,600 pp.