In late June, the La Crescent, Minnesota, environmental section measured the growth of tree seedlings at Kain’s Switch South near New Albin, Iowa. Approximately 600 seedlings were planted in late May, part of a research project conducted by the University of Minnesota through a Cooperative Ecosystems Studies Unit agreement with the Corps’ recreation and natural resource branch, environmental section. The project aims to improve understanding of floodplain forest processes, restoration and management.“Through this study, we hope to better understand the factors limiting viable floodplain forest regeneration and develop target tree seedling guidelines to improve our effectiveness in restoring forests. Forests can be degraded by a range of health threats, including invasive species, emerald ash borer and Dutch elm disease,” said Andy Meier, Corps forester.The project consists of nine separate planting blocks, with 64 seedlings to a block totaling 576 trees, under intermediate canopy density. The nine blocks are split across three flooding gradients: an area of high inundation with 30-40 days flooded during the growing season; an area of intermediate inundation with 10-30 flooding days; and an area of low inundation with 1-10 flooding days.Over the next few years, the Corps will monitor seedling mortality and growth rates across four tree species: swamp white oak, silver maple, American sycamore and common hackberry. Staff will measure and record each seedling’s height and root collar diameter while checking for leaf dieback and deer browse.If the seedlings survive, they should establish quickly. The intermediate light conditions in the planting locations inhibit the growth of reed canary grass and other vegetation, which should allow the seedlings to grow above the height of the competition more effectively.The initial phase of the project will be completed by 2021. If the trees survive, the plantings will continue to be monitored for many decades to come, Meier said.-30-