2006 National Sunflower Association Survey Project Leader: Dr. Duane R. Berglund, NDSU Extension Agronomist and Professor of Crop Science.
2009 National Sunflower Association Survey Project Leader: Dr. Duane Berglund, Retired NDSU Extension Agronomist and Professor Emeritus- Crop Science.
2005 National Sunflower Association Survey Project Leader: Dr. Duane R. Berglund, NDSU Extension Agronomist and Professor of Crop Science.
2009 National Sunflower Association Survey