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  • Plant Pest Diagnostics Center

    Don Joley

    Don Joley

    Senior Seed Botanist (retired annuitant)

    Plant Pest Diagnostics Branch, California Department of Food & Agriculture
    3294 Meadowview Road, Sacramento, CA 95832-1448, U.S.A.
    916-738-6700 office, 916-262-1190 fax, djoley@cdfa.ca.gov


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    Curriculum vitae


    • Master of Science, Plant Science, 1974, California State University, Chico
    • Bachelor of Arts, Biological Science, 1969, California State University, Chico.


    • 02/06-present Senior Seed Botanist, CDFA Seed Laboratory
    • 02/03-01/06 Associate Seed Botanist, CDFA, Seed Laboratory
    • 06/90-01/03 Associate Environmental Research Scientist, CDFA, BCP
    • 03/82-06/90 Pest Management Specialist III, CDFA, BCP
    • 04/78-03/82 ASB II/ Pest Management Specialist, CDFA, BCP
    • 12/76-04/78 ASB I/II, CDFA, Control and Eradication
    • 02/76-12/76 Agricultural Services Biologist (ASB) I, CDFA, Biological Control Program (BCP)

    Area of Current Specialty/Responsibility:

    • Perform complex and specialized analyses on seed taxonomic problems
    • Identify native and foreign plant propagules on a worldwide basis
    • Primary responsibility for seed quarantine and feed mill approval programs


    1. Joley, D.B., D.M. Maddox, D.M. Supkoff, and A. Mayfield. 1992. Dynamics of yellow starthistle (Centaurea solstitialis) achenes in field and laboratory. Weed Science 40:190-194.
    2. Joley, D. B., D. M. Maddox, B.E. Mackey, S.E. Schoenig, and K.A. Casanave. 1997. Effect of light and temperature on germination of dimorphic achenes of Centaurea solstitialis in California. Canadian Journal of Botany 75:2131-2139.
    3. Joley, D. B., D. M. Maddox, S.E. Schoenig, and B.E. Mackey. Parameters affecting germinability and seed bank dynamics in dimorphic achenes of Centaurea solstitialis in California. 2003. Canadian Journal of Botany 81:993-1007.
    4. Maddox, D.M., R. Sobhian, D.B. Joley, A. Mayfield, and D. Supkoff. 1986. New biological control for yellow starthistle. California Agriculture 40(11&12): 4-5.
    5. Maddox, D.M., D.B. Joley, A. Mayfield, and B.E. Mackey. 1991. Impact of Bangasternus orientalis (Coleoptera: Curculionidae) on achene production of Centaurea solstitialis (Asterales: Asteraceae) at a low and high elevation site in California. Environmental Entomology 20(1): 335-337.
    6. Maddox, D.M., D.B. Joley, D.M. Supkoff, and A. Mayfield. 1996. Pollination biology of yellow starthistle (Centaurea solstitialis) in California. Canadian Journal of Botany 74:262-267.
    7. Maddox, D.M., D.B. Joley, and M.J. Pitcairn. 2007. Studies on the biology of the gorse seed weevil, Exapion ulicis (Forster 1771), in northern California (Coleoptera: Curculionidae). Pan-Pacific Entomologist. 83(1):32-40.
    8. Supkoff, D.M., D.B. Joley, and J.J. Marois. 1988. Effect of introduced biological control organisms on the density of Chondrilla juncea in California. Journal of Applied Ecology 25:1089-1095.
    9. Turner, C.E., R. Sobhian, D.B. Joley, E.M. Coombs, and G.L.Piper. 1994. Establishment of Urophora sirunaseva (Hering) (Diptera: Tephritidae) for biological control of yellow starthistle in the western United States. Pan-Pacific Entomologist 70 (3):206-211.
    10. Woods, Dale M., Michael J. Pitcairn, and Donald B. Joley. 2000. Sequential impacts of endemic pathogens , exotic mollusks and insects on yellow starthistle (Centaurea solstitialis) in California. Proceeding of the 10th International Biological Control of Weeds Symposium, Bozeman, Montana.