•  Director, Interdisciplinary Plant Group (IPG), University of Missouri (2011 – 2022)
• Chair, 11th Annual International Society for Root Research (ISRR) Symposium (2021)
• Interim Director, Division of Plant Sciences, University of Missouri (2005 – 2008)
• Associate Director, Division of Plant Sciences, University of Missouri (2005)
• Chair, Department of Agronomy, University of Missouri (2000 – 2005)