Chippewa National Forest, MN

Studies of the leading edges of earthworm invasion by Cindy Hale and landscape-scale patterns of invasion by Andy Holdsworth take place in sugar maple-dominated forests.


Second growth northern hardwoods near Leech Lake, Minnesota.

Second growth northern hardwoods near Leech Lake, Minnesota. Photo: Dave Hansen, University of Minnesota Agricultural Experiment Station.

Base of sugar maple, no earthworms.

Base of sugar maple, no earthworms. Photo: Dave Hansen, University of Minnesota Agricultural Experiment Station.

Base of sugar maple, with earthworms.

Base of sugar maple, with earthworms. Photo: Dave Hansen, University of Minnesota Agricultural Experiment Station.

Nodding Trillium above and Bellwort below, two species negatively impacted by European earthworms.

Nodding Trillium above and Bellwort below, two species negatively impacted by European earthworms. Photo: Dave Hansen, University of Minnesota Agricultural Experiment Station.

photo of bellwort