From Glaciers to Gardens: How Earthworms Shaped Northeastern Forest Soils

Join us at the Museum for an illustrated talk by Annise Dobson, Associate Research Scientist at Yale University, who will share how the history of earthworms in North America has been shaped by ancient glaciation, centuries of human-mediated introductions and spread, and multiple waves of biological invasion.
This talk traces that history from the post-glacial forest assembly absent of earthworms and spread of European earthworms through agriculture, logging, road building, horticulture, and fishing bait. We then examine contemporary invasion of jumping worms, and how different earthworm groups reshape habitats by accelerating leaf-litter breakdown, altering soil structure and nutrient cycling, and changing conditions for seeds, seedlings, and fungal communities. Finally, we consider how earthworm impacts interact with other stressors such as invasive plants, overabundant deer, and climate-driven shifts in temperature and moisture, and we outline practical steps for reducing spread and supporting conservation and management goals.
WHEN: Sunday, August 16, 2026
TIME: 4-5 p.m.
PLACE: In person at the Museum and virtual via zoom
Annise Dobson is the Director of Research Programs, Associate Research Scientist, and Lecturer in the Department of Ecology & Evolutionary Biology and the School of the Environment at Yale University. She grew up on a farm in the Ottawa Valley in Ontario, Canada, and completed her PhD at Cornell University. Her research focuses on plant-soil interactions and the ecosystem-level impacts of invasive species. Her work investigates the cascading effects of jumping worms on forest health, from the soil food web, up to the seedling layer, and beyond. Dr. Dobson is passionate about translating scientific discovery into practical land management guidance and is actively involved in outreach to help land managers and the public understand and respond to this pressing ecological threat.
PHOTO CREDITS: Grant Dobson