Native earthworms did not survive the Pleistocene glaciations in Minnesota.� The earthworms currently found in the state are mostly Eurasian, and result from a biological invasion that followed European settlement in the 1800s.� Although many regions of the state are now infested, some areas remain earthworm-free.� The extent of the earthworm invasion in west central Minnesota has remained undocumented.� Recent studies have reported negative impacts of Eurasian earthworms on Minnesota forests, and research has linked invasive earthworms to the invasion of European buckthorn Rhamnus cathartica (European buckthorn).� We surveyed for earthworms using the liquid extraction method at 144 sample sites spread across six forested study areas in west central Minnesota. �Earthworms were measured and categorized to three functional groups: epigeic (litter dwelling), endogeic (shallow soil dwelling), and anecic (deep burrowing) species. We sampled vegetation and measured soil moisture and the depth of soil layers at each earthworm sample site.� Worm abundance varied greatly among our sample sites. �At the extreme, one of our study areas, Glacial Lake State Park, appears to be largely earthworm-free.� Contrary to published studies suggesting a link between earthworms and invasive R. cathartica, our results show an inverse correlation between earthworm and R. cathartica abundance.� Sites without worms have significantly more R. cathartica stems (p=0.03).� As expected, earthworms are associated with decreased organic layer soil depths at sample sites within our study areas.� Earthworms are also associated with higher soil moisture.�