IOWA — The IOWA Department of Agricultural and Biosystems Engineering and the Department of Natural Resource Ecology and Management are studying the process behind weeding out certain species of trees in forests to help other trees grow, and using those weeded-out trees for water quality practices. The underutilized trees will be chopped into woodchips, a common media for water quality improvements. Those woodchips move from the forest to farmlands around the Midwest in the form of bioreactors, a woodchip-filled trench that filters nitrate from field drainage, keeping water clean. The project is funded by the United States Department of Agriculture (USDA) and is being investigated by ABE professor Michelle Soupir, water quality engineer Ji Yeow Law, engineer Andy Craig and Billy Beck, an assistant professor in the Department of Natural Resource Ecology and Management.