Interview with Dr. Tanya Dahms, Professor of Biochemistry and Organic Land Care Advocate
Seamus Masterson, HFC Student Researcher at Georgetown University, interviewed Dr. Tanya Dahms to learn about her efforts to reduce chemical exposure at the University of Regina, in Canada, where she works as a Professor of Biochemistry. Aside from using the Plant Health Care model on campus, Tanya also conducts research on how microbial and human cells respond to environmental stressors like pesticides and antifungal agents. Continue reading below for an excerpt of their conversation, and you can click here to read their discussion in full!
Dr. Scott Wilson (grasslands researcher) with Dr. Tanya Dahms and son Ayden standing in a plot that had been assessed by the students for turf composition.
Seamus:
I really wanted to talk to you about the plant health care model. But before I get into that, how did you first get involved in environmental science and what brought you to this field?
Tanya:
Well, honestly, it was actually my frustration with the city, the province, and the campus in terms of pesticide use. In 2002, we proposed a pesticide ban to the city, and they proposed the Integrated Pest Management model, which in this specific case is just a fancy term for using a whole lot of pesticides. My hometown of Guelph, Ontario, also proposed a complete ban on the cosmetic use of pesticides the same year and won. Unfortunately, we did not win our ban in Regina, Saskatchewan, Canada, because the prairies really got sold on pesticide use and pesticides are still used by the city, province, and citizens on their lawns. Next, in 2007, I co-founded a UN initiative, the Saskatchewan Regional Center of Expertise (SK RCE) on Education for Sustainable Development. I continue to coordinate the Health and Healthy Lifestyles thematic of the SK RCE. So again, another action project, and then in 2011, I got so frustrated with the lack of movement on pesticide bans that I actually reoriented my research and was awarded NSERC (Natural Sciences and Engineering Research Council of Canada) funding to study the impact of herbicides on non-target organisms. We did experiments to determine how 2, 4-D (2,4-Dichlorophenoxyacetic acid) impacts bacteria, fungi and also human cells. We came back to the city with a proposed ban in 2012. And at this point, I brought my grad student with me, and we had lots of data to present. We continue that research now: we're looking at the impact of glyphosate and 2,4-D on microbes of the human microbiome based on one study showing a link between pesticides and gut microbiome health. So that's kind of my trajectory. There's a lot of Big Ag here. And so people don't even really blink when they use pesticides.
Seamus:
You mentioned that the Plant Health Care Model is an alternative to pesticides. Can you elaborate on how that research is done and what that whole process is like?
Tanya:
Sure, well, it's a really well established model, actually. The whole idea of the plant health care model is really to advantage the soil with microbes and whichever species you're trying to propagate. So in the beginning of spring, what you do is you flood the area, overwatering and overseeding, and then throughout the season you high mow so that you can give the grass a headstart and to not give the invasives a foothold. Throughout the summer, we use compost tea. We just take the bottom of the compost from the adjacent organic garden, throw it in water with a carbon source like molasses or sugar, stir it up (summer is best for the right temperature), and then the students would just distribute that over the lawn along with kelp fertilizers. All those things are really meant to enrich the soil with microbes so that you have a healthy soil base. To give the grass more of an advantage, they would dethatch (eliminates mulch that prevents growth) and then aerate the soil by cutting or plugging.
This is like a really well worked out model, so I can take no credit for that. The only reason it became a Citizen Science Project is because we had to convince Wascana Center Authority that this was going to work. I remember talking to our VP academic at the time (now our acting president) and he said if you guys do this project in the center green, and the sod has to be replaced, it will cost a lot. I said look, garnish my wages if it comes to that (laughs). Then he told me how much it was, like $90,000 or some crazy amount.
University of Regina main campus is designed in the round. Areas outlined in red are ideally suited for early stages of the plant health care model to eliminate trafficking pesticide by foot into the buildings.
To strategically choose plots, we (Health and Safety Officer and some of our facilities management people, myself, the director of Wascana Centre Authority and the main groundskeeper there) looked at the campus map to choose areas with the most foot traffic into the university. Typically in the summer, people come onto the center green, walk across the grass and return to the buildings. And of course, as you know, most buildings do not have HEPA air filters, so if we track pesticides into the university they just circulate. Our university is relatively small, mostly surrounding the center green, so the first two test plots were near the center green and then we expanded into it. We were lucky because another group called the Regina Public Interest Research Group (RPIRG) has an organic garden adjacent to the center green, and so it made sense to team up with them as well. Once we had the project going, we teamed up with RPIRG, and paid their gardeners to help us do the Plant Health Care Model (PHCM), and we spun it into the citizen science project.
Seamus:
And you had some help from high school students, is that correct?
Tanya:
Yes, so it started out on just two small adjacent plots, using the PHCM and status quo. I conscripted a now retired grasslands researcher, Dr. Scott Wilson who could teach students to do turf analysis. He would rope in a rectangular area that was chosen randomly, and then evaluate the percentage of each grass species in that area. Dr. Chris Yost, a microbiologist, also agreed to contribute by teaching students how to take core soil samples, which the students then analyzed in our research labs. Their teachers (Heather Haynes and Nicole Anderson) got kits for pH, nitrogen, phosphorus, and potassium. Once all the data had been recorded, I would bring them back to the university, we would meet in the boardroom, and I would guide them on how to analyze the data effectively.
Miller high school students analyzing soil samples in a University of Regina. microbiology lab.
Seamus:
Have you come across any challenges that have disrupted this plant health care model on campus?
Tanya:
When I first started, I was pretty naive, and I thought we could follow all the PHCM steps, but we hit a drought year and water ban our first year, so that was a huge challenge. It didn't seem to impact things that much though. The nice thing was that WCA donated the seed and once we had connected with facilities management to control the water, then we could water more often once the water ban was lifted. I learned that you certainly do not need to do every step each year, and if you did it's likely overkill. If you have time to do it on your own lawn, then go for it, but if you're a grounds manager, there is no way you are going to be doing all of this. I think we did the dethatching once and the aeration once over seven years. It was frustrating that trucks would drive on the edge of turf during transition seasons, making a clear path for invasive. The biggest hurdle was starting, and getting permission. I started harping about this to campus officials, first at the Executive Council around 2005, 2006 until they pointed out that perhaps it was the wrong venue to talk about it. At that point, we started the year and a half process of “generous listening” with members of WCA and finally landed on trying the PHCM on campus.
Seamus:
Are campus officials and administrators aware of the benefits that your research does?
Tanya:
Absolutely. The project was initially funded by a special sustainability fund on campus and subsequently we have made two strategic plans, the first of which sustainability was somewhat embedded and our most recent plan boasts sustainability as an overarching theme, along with Indigenization, giving power and influence to those that are native to the area. The project has been promoted on the President’s webpage and we are currently in the process of rethinking a sustainable campus, and of course, this is just one piece of the puzzle.
Seamus:
Knowing that this whole process began around 2015, how has the research project held up to this day? Has the research changed at all?
Tanya:
Well, the plant health care model I do not consider part of my research, which uses microscopy and biochemical tests to study the impact of herbicides on bacteria, fungi and human cells. Rather, I consider this a community project. Professors are teachers, researchers, administrators, and we do community service, so I consider this to be part of my community service. I think if we ever published anything on it, it would be in an education journal, showing how you can take education outside the classroom to make changes in an institution, and even bring it to high school students. Since the pandemic we haven't done any measurements, obviously, but we have that baseline data that we can go back to, so I think that in the future, we'll continue in some way. If we do, we'll probably try to work with the city since it has autonomy over its grounds. Again we would work with some local high schools. In terms of my research, we continue to look at how herbicides impact non-target organisms important for the soil, along with our cells, our bodies, and our microbiome.
Seamus:
Aside from that, are you involved in any other kind of exciting projects, personal projects of yours that take up your day to day?
Tanya:
Well, online teaching right now is pretty intense, but from a personal perspective, I am definitely still an environmental activist. So I still coordinate part of the SK RCE and am involved in For Our Kids Saskatchewan, which is a Canadian movement to tackle climate change and action for our kids’ collective future. So I'm really heavily involved in climate action. Last semester, I had a Friday class, which is during the climate action strikes, so I moved to an asynchronous Friday class and I encouraged my students to go to the climate strikes protests with me!
We also have a four year old son, so he keeps us super busy and engaged!
Seamus:
Well, thank you so much for agreeing to be interviewed. So many of us at Herbicide Free Campus are inspired by your dedication to understanding the long term effects of dangerous herbicides and pushing for healthier and more substantial legislation. Best of luck with your research moving forward!