Brent A. Holtz Ph.D.

County Director and Farm Advisor
Cooperative Extension San Joaquin County
2101 East Earhart Avenue, Suite 200
Stockton, CA 95206
(209) 953-6124 Create VCard


Dr. Brent Holtz has been a Pomology Farm Advisor for the University of California for 29 years and County Director in San Joaquin County’s UC Cooperative Extension office for 13 years.  Brent was raised on an almond ranch in the Northern San Joaquin Valley, attended schools in California: Modesto Junior College (A.A.), California Polytechnic State University, San Luis Obispo (B.S.), and earned both M.S. and Ph.D. degrees in Plant Pathology from the University of California, Berkeley.  Following graduation in 1993, Dr. Holtz was a post-doctoral research associate with Dr. Themis Michailides at the University of California, Davis, before becoming a Pomology Farm Advisor in Madera County in 1994. 

Brent's research and education programs are focused on growing almonds in a sustainable manner in the San Joaquin Valley of California, helping deciduous tree fruit growers in production agriculture find more environmentally friendly ways to produce their crops without compromising product quality or price.  Brent is currently leading a research effort on whole almond orchard recycling where removed orchards are ground-up and incorporated into the soil to increase soil organic matter and soil water holding capacity.  Brent is currently serving on San Joaquin County’s Agricultural Advisory Board and the San Joaquin Farm Bureau Federation Board of Directors. 


Ph.D. Plant Pathology, UC Berkeley. 1993
M.S. Plant Pathology, UC Berkeley. 1989
B.S. Biology, Plant Pathology, Entomology, California Polytechnic State University, San Luis Obispo. 1986
A.A. Science and Mathematics, Modesto Junior College. 1983


  • Finalist, Fresno, CA
    Presented by Friends of Agriculture,  2002
  • Proclamation of Achievement Award
    Presented by Madera County Board of Supervisors,  2002
  • National Achievement Award, Albuquerque, New Mexico,
    Presented by National Association of County Agricultural Agents,  2001


Pomology, deciduous tree fruits and nuts, plant pathology, Whole Orchard Recycling

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Peer Reviewed

California Agriculture Article Contributions

ANR Workgroup Associations

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