The annual Iowa State University (ISU) Rhodes Research and Demonstration Farm field day will be held Tuesday, July 9, from 4:30-8:30 p.m. This event gives farmers, ranchers, and other ag professionals a firsthand view of current research and demonstration projects. Barry Dunn, a range livestock production specialist, South Dakota State University, is the keynote speaker. He will present "Factors that Make a Difference in Cow-Calf Profits."