Three Sisters Project Continues to Fuel Collaborative Research in Northern Ontario
University of Guelph researchers are continuing to explore how an Indigenous planting practice called the “Three Sisters” could contribute to future small-scale, sustainable farming and community-driven research.
In collaboration with an Indigenous-led non-profit and the Ontario Ministry of Agriculture, Food and Agribusiness (OMAFA), they are observing how crop combinations of the “sisters” (corn, squash, bean, and sometimes sunflower) affect both beneficial and pest insect populations and weed control. Project partners are working to co-develop planting methods, bring people together and build relationships that will lead to sustainable, resilient ecosystems.
Published: September 18, 2025
Lead photo: Test plots are prepared for the Three Sisters (corn, squash, bean and sometimes sunflower) at the Ontario Crops Research Centre. Photos courtesy of Melinda Drummond and Elaine Roddy.
Learning from the Three Sisters
When planted together in mounds, the Three Sisters work together: the corn or sunflower provide scaffolding for the beans to climb; the beans fix nitrogen in the soil, which helps the plants grow. The squash shades out the weeds and deters pests.
U of G became involved in Three Sisters work led by University of Manitoba researcher Dr. Kyle Bobiwash and entomology master’s student Victoria Smelko in 2022. Smelko’s research sought to evaluate the insect populations attracted to the plots.
To contribute Ontario-based data, U of G agronomist Dr. Joshua Nasielski and research technicians Nathan Mountain, Melinda Drummond and Kim Jo Bliss joined the project. Elaine Roddy, a vegetable crops specialist at OMAFA, provided agronomy advice.
The Ontario-based researchers collected data from several sites, including Ontario Crops Research Centre (OCRC) sites in Emo and New Liskeard, which are owned by the Government of Ontario through its agency Agricultural Research and Innovation Ontario (ARIO) and managed by the University of Guelph through the Ontario Agri-Food Innovation Alliance.
While this first phase of research looked at pollinators within the Three Sisters planting, the research directions are meant to evolve to address questions and challenges raised by local communities.
Ontario sites exploring new lines of research
With local community input and financial support from the Ontario Agri-Food Innovation Alliance, the project is headed in several new directions.
In 2024, Three Sisters plots were added at the Ontario Crops Research Centre in Ridgetown and OMAFA horticulture specialist Kris McNaughton joined the team.
Trials are replicated at the three research sites (Ridgetown, Emo, New Liskeard) to see how strategies work under very different growing conditions across the province.
Based on conversations with Kitchener-based Anishnabeg Outreach, the primary focus for 2025 and 2026 is weed control.
OMAFA’s Roddy explains that while squash traditionally suppresses weeds in the Three Sisters plantings, conventionally managed land has deep “weed banks” that make management very time-consuming for community gardens that are run by volunteers. Furthermore, they were seeking a natural solution.
With that in mind, a trial to compare four different treatments was initiated in 2025. Plots either had live mulch (winter wheat) applied in spring, dead mulch (straw) applied in spring, tillage in spring or chemical herbicide treatment. Similar trials will be repeated in 2026.
The pollinator component of the research is also continuing, although less in-depth than the first phase of the project.
Learnings from the Three Sisters project will help to inform other research initiatives. Weed control results will be shared with at least two other projects: the White Corn Project, which started as a partnership between the University of Western Ontario and Agriculture and Agri-Food Canada (AAFC), and with the Alliance Special Initiatives project Braiding Food Systems, which seeks to identify and introduce viable Indigenous heritage seed varieties suited to northern climates for the benefit of plant, animal, and human health.
Engaging local perspectives
Having the three sites creates touchpoints for local engagement, inviting input and engagement from nearby communities.
Holly Byker, manager of the Emo and New Liskeard sites, says it is too early to see results of the different weed-suppression techniques, but that the team is also using this time to reach out to new potential community partners and build relationships that will inform and sustain the research.
Roddy notes that there is so much knowledge already developed in First Nations communities across the province, and this research can help start conversations and bring people together to share their knowledge.
Byker says the Three Sisters plots attract attention and are conversation-starters with passersby.
In that respect, the project is doing its job to facilitate the co-development of new methods, bring people together and build relationships that will lead to sustainable, resilient ecosystems.
This research is taking place at the Ontario Crops Research Centre sites in Emo, New Liskeard and Ridgetown. The Ontario Crops Research Centre is owned by the Government of Ontario through its agency, Agricultural Research and Innovation Ontario, and is managed by U of G through the Alliance.
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