SDSU sets dates of research farm field days South Dakota State University has set tentative dates for this yearâ�?�?s field days at its research farms around South Dakota. Scientists of the South Dakota Agricultural Experiment Station and specialists of the South Dakota Cooperative Extension Service will be on site on those dates to discuss the latest SDSU research on weed control, soil fertility, insects, plant diseases, crop varieties and other topics. SDSU Extension Crops Specialist Bob Hall said the dates of particular events could change depending on weather and other factors in the growing season. SDSU will announce any changes ahead of time. The field day at the Southeast Research Farm, Beresford is scheduled July 9, from 3 p.m. to dusk.