Chairman of the Board of the Research Institute of Organic Agriculture (FiBL) Germany

2005-2008Dean of the Faculty of Organic Agricultural Sciences of the University of Kassel
1998-2021Scientific Head of the Hessian State Estate Frankenhausen (Research farm of the University of Kassel)
1997-2021Head of the Department of Organic Farming & Cropping Systems of the University of Kassel
1995Habilitation to the topic "Residual nitrogen out of periennial field fodder: improvement of its use through crop rotation and cropping methods under conditions of organic agriculture" at the Faculty of Agriculture of the University of Bonn
1992-1997Guest professor, since 1995 ordinary professor, since 1996 Head of the newly founded Institute Organic Agriculture at the University of Natural Resources and Applied Life Sciences, Vienna
1985-1989Dissertation to the topic "Incorporation of grass clover in organic agriculture" at the Institute of Crop Science, Department of Soil Management and Applied Soil Physics of the University of Bonn (Prof. Dr. H. Franken)
1976-1982Study of Agricultural Sciences at the University of Bonn


  • Research Institute of Organic Agriculture (FiBL), Chairman of the Executive Board
  • International Society of Organic Agriculture Research (ISOFAR)
  • German Society for Crop Sciences
  • German Association of University Professors and Lecturers (DHV)
  • German Soil Science Society (DBG)
  • Association of German Scientists (VDW)
  • Advisory Committee on the Federal Organic Farming Scheme (BÖLN/BLE)
  • EIP Advisory Council Hesse
  • Scientific Advisory Board of the Organic Food Production Alliance (BÖLW)
  • Board of Trustees of the Zukunftsstiftung Landwirtschaft (ZSL)
  • Board of Trustees of the Schweisfurth Foundation
  • Steering Committee Gesellschaft für Ressourcenschutz (GfRS)