Collaborative Staff

Stephen Kaffka, Director

steve-kaffkaStephen Kaffka is Director of the California Biomass Collaborative and extension specialist in the Department of Plant Sciences at the University of California, Davis. He is chair of the BioEnergy Work Group for the University of California’s Division of Agriculture and Natural Resources. He has advised the California Energy Commission on agricultural and sustainability issues, and serves as an ex officio member of the Bioenergy Interagency Work Group. He is a member of the National Research Council’s committee on Economic and Environmental Impacts of Increasing Biofuel Production. From 2003 to 2007 he was director of the Long Term Research on Agricultural Systems Project. As director he led the development of current and new projects focusing on sustainable agriculture. His commodity assignments include sugar and oilseed crops, and has worked on agriculture and water quality projects. He has Ms and Ph.D. degrees from Cornell University in agronomy and a B.S. from the University of California at Santa Cruz in biology. For more information about Stephen Kaffka, visit his faculty page at Plant Sciences.

Mark Jenner, Biomass Systems Economist


Mark Jenner is a Biomass Systems Economist with the California Biomass Collaborative. His expertise is in biomass production and conversion technologies, environmental and energy policies, and creating and adding value to biomass.

Since 2009, Mark Jenner has been modeling the adoption economics of purpose grown energy crops with the California Biomass Collaborative, at the University of California Davis. In 2003 he began his consulting firm Biomass Rules, LLC, which conducts feasibility studies on value-added biomass projects and biomass inventories. In 2006, Mark wrote the BioTown, USA Sourcebook for the State of Indiana and writes the biomass energy outlook column for BioCycle Magazine.

Mark Jenner has a PhD in ag. economics in production systems, two MS degrees in manure management, a BS in agronomy, and 30 years of professional experience spanning three continents.


Graduate Student Researchers

  • Jacquelyn Button
  • Garrett Liles


Post-Doctoral Scholars

  • Jimin Zhang