Dave Mortensen has spent his career working on sustainable design of cropping systems. Early on, much of this work was pest management centered. More recently, his work has centered on cropping systems design and function and his work has taken on a decidedly landscape approach to framing questions. He is best known for his work on sustainable pest management systems. His work has helped shape national policy with both the USDA and EPA regarding pesticide use and regulations associated with genetically modified crops. Mortensen also serves holds the scientist seat on the USDA's National Organic Standards Board. Mortensen rose to the rank of Distinguished Professor at Penn State before assuming his new role at UNH in 2018.