Exotic earthworms (Amynthas agrestis) are invading eastern forests. These earthworms consume the organic horizons of the forest floor, often removing leaf litter within several years of invasion. This leads to important changes in soil carbon, nutrients (e.g. nitrogen and calcium), soil microclimate, hydrology, soil organisms, and plant community assemblages.
The Northern Research Station is characterizing ecosystem responses across a range of earthworm species densities in maple and hemlock dominated forest systems, and monitoring earthworm invasion fronts located in the Huron Mountains in northern Marquette County, MI.
Exotic earthworms have also been found competing with native soil microfauna in the southern Appalachians:
- Spatial variability of an invasive earthworm (Amynthas agrestis) population and potential impacts on soil characteristics and millipedes in the Great Smoky Mountains National Park
- Occurrence of an exotic earthworm (Amynthas agrestis) in undisturbed soils of the southern Appalachian Mountains
The International Institute of Tropical Forestry in Puerto Rico recently hosted the second Latin American symposium on invasive earthworms: Earthworms as Invasive Species in Latin America.