05/04/2026
"Not so Nice," Earthworm Invaders! Saturday, May 23, 2026, 10:00 AM
Join naturalist Eowyn Bates for a walk in the woods to learn why Earthworms are not helpful to the soil. Alpena State Road, on right before stream crossing. Watch for signs
Worms, they're good for your soil, right? As it turns out, that's not exactly true! In Michigan, and most of North America, ALL earthworms are invasive and are destroying our forests! During the Ice Age, glacial activity killed our native earthworms off completely, and in the thousands of years since, nature has adapted to their absence. Without worms, the leaves that fell from trees would build up over time, creating a thick layer called "duff." This could get quite deep, ranging from a foot to up to your knee!
Plants, animals, and fungi had all adapted to use this duff, which would hold moisture while providing shelter and food. However, when European settlers arrived in North America, they brought along their earthworms with them, and the invasive worms quickly spread from there.
Now, the duff has largely been destroyed. Seeds can't germinate, as they cannot handle being moved and rotated by worm activity. Animals have nowhere to hide, and mushrooms--such as morels--have lost their food source. Trees are weakening and dying without the duff covering their roots, which used to help hold in moisture and protect against predators. Forest fires have also become much more of a threat, as without the moisture provided by the duff, the forest floor dries out much more quickly, providing tinder.
In this field trip, we will explore two areas of Alpena State Road: one with worms, and one without. We will look at the plants and animals found in each and see the impact worms have had on the forest firsthand!
Caution, Alpena State Road is quite rough, so a strong vehicle with four-wheel-drive is recommended.
The program is an Earth Week Plus Adventure. It is free, and suitable for all ages. See the complete schedule at earthweekplus.org.