distribution of southern California walnut-dominated forests and
woodlands is limited to the Santa Clarita River drainage in the vicinity
of Sulphur Mountain, small stands in the Simi Hills and Santa Susana
Mountains, the north slope of the Santa Monica Mountains, and the San
Jose, Puente, and Chino hills. The best remaining stands are in the San
Jose Hills . Outside of this range, southern California walnut
occurs in Santa Barbara, western San Bernardino, and northern San Diego
counties . It is conspicuously absent from the coastal foothills of
the Santa Ana Mountains, San Diego County .
Southern california walnut is cultivated in Hawaii .
- 8. Griffin, James R. 1977. Oak woodland. In: Barbour, Michael G.; Malor, Jack, eds. Terrestrial vegetation of California. New York: John Wiley and Sons: 383-415. 
- 10. Holstein, Glen. 1984. California riparian forests: deciduous islands in an evergreen sea. In: Warner, Richard E.; Hendrix, Kathleen M., eds. California riparian systems: Ecology, conservation, and productive management: Proceedings of a conference; 1981 September 17-19; Davis, CA. Berkeley, CA: University of California Press: 2-22. 
- 25. Quinn, Ronald D. 1990. The status of walnut forests and woodlands (Juglans californica) in southern California. In: Schoenherr, Allan A., ed. Endangered plant communities of southern California: Proceedings, 15th annual symposium; 1989 October 28; Fullerton, CA. Special Publication No. 3. Claremont, CA: Southern California Botanists: 42-54. 
- 33. Vogl, Richard J. 1976. An introduction to the plant communities of the Santa Ana and San Jacinto Mountains. In: Latting, June, ed. Symposium proceedings: plant communities of southern California; 1974 May 4; Fullerton, CA. Special Publication No. 2. Berkeley, CA: California Native Plant Society: 77-98. 
- 38. St. John, Harold. 1973. List and summary of the flowering plants in the Hawaiian islands. Hong Kong: Cathay Press Limited. 519 p. 
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