Plant Pest Diagnostics Center
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Dr. Fred HrusaSenior Plant Taxonomist Plant Pest Diagnostics Branch, California Department of Food & Agriculture
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Curriculum vitae
Education
- Doctor of Philosophy (Plant Biology) - University of California, Davis. 1995. Dissertation: "The systematics and evolution of Rhododendron occidentale (Torrey & A. Gray) A. Gray (section Pentanthera; subf. Rhododendroideae; Ericaceae)"
- Master of Science (Botany) - University of California, Davis. 1991. Thesis: "A morphometric analysis of variation in Rhododendron occidentale (T. & G.) Gray, among populations native to ultrabasic and non-ultrabasic substrata (Ericaceae: Rhododendroideae)"
- Bachelor of Science (Ornamental Horticulture) - California Polytechnic State University, San Luis Obispo. 1983.
Current Employment
- 1997-present, Senior Plant Taxonomist, California Department of Food and Agriculture
Publications
- Stebbins, G. L., & G.F. Hrusa. 1995. The North Coast Biodiversity Arena in Central California: A New Scenario for Research and Teaching Processes of Evolution. Madrono 42 (2): 269-294.
- Hrusa, G.F., & J.C. Hunter,1996. Black Butte Research Natural Area, Los Padres National Forest, San Luis Obispo County, California. Description, Vegetation and Flora. USDA Forest Service, Pacific SW Research Station, Albany CA. 94 pp.
- Brennan, E.B., R.J. Gill, G.F. Hrusa, & S.A. Weinbaum. 1999. First record of Glycaspis brimblecombei (Moore) (Homoptera: Psyllidae) in North America. The Pan-Pacific Entomologist, 75:11, 55-57.
- Villegas, B., D.A. Mayhew, F. Hrusa, & J. Balciunas. 2000. Survey of Chaetorellia seedhead flies on Cirsium thistles in close proximity to Centaurea spp. in California. Pages 62-63 in D.M. Woods, ed. In, Biological Control Program Annual Summary, 1999. California Department of Food and Agriculture, Plant Health and Pest Prevention Services, Sacramento, CA.
- Brennan, E.B., G.F. Hrusa, S.A. Weinbaum & W. Levison. 2001. Resistance of Eucalyptus species to Glycaspis brimblecombei (Homoptera: Psyllidae) in the San Francisco Bay Area. The Pan-Pacific Entomologist 77(4). 249-253.
- Sorensen, J.T., F. Hrusa & T. Tyler, 2001. Origin of the Sudden Oak Death (SOD) pathogen and its potential impact: a working hypothesis. California Plant Pest and Disease Report 19 (3-6): 47-57 + maps.
- Hrusa, F., B. Ertter, A. Sanders, G. Leppig, & E. Dean 2002. Catalogue of non-native vascular plants occurring spontaneously in California beyond those addressed in the Jepson Manual - - Part I. Madrono 49(2): 61-98.
- Ayres, D., F. Ryan, F. Hrusa, & P. Akers, 2005. Tumbleweeds of California: Who, what, where and how. Poster presented at the Annual Meeting of the California Invasive Plants Council.
- Gaskin, John F., Frederick J. Ryan, G. Frederic Hrusa, and Jason P. Londo, 2006. Genotype diversity of Salsola tragus and potential origins of a previously unidentified invasive Salsola from California and Arizona. Madrono 53(3): 244-251.
Papers currently in review
- Dean, E., F. Hrusa, G. Leppig, B. Ertter, A. &Sanders. (in review). Catalogue of non-native vascular plants occurring spontaneously in California beyond those addressed in the Jepson Manual – Part II. Madrono (in review).
- Hrusa, G.F., & J.F. Gaskin, (in review). Salsola tragus sensu auct. California (Salsola sect. kali: Chenopodiaceae): characterization and status of Salsola australis R. Br. and the autochthonous species Salsola ryani sp. nov. Madrono (in review).



