February 2013

European earthworms have only recently been recognized as an invasive threat to the hardwood forests of the Great Lakes Region of North America, yet mounting evidence indicates that the invasion of earthworms into forests that had been earthworm-free since at least the last glacial maximum is profoundly and fundamentally altering nutrient cycling, soil structure, and the forest floor communities of these ecosystems. Less attention has been given to how earthworm invasions influence tree growth and productivity.