Fighting fungi and studying pathogens with one foot in the forest and one foot in the lab.
September 2025
Nicolas Feau didn’t set out to become a forest pathologist. But he took the first steps on the path to his profession as a child searching for mushrooms in the woods with his parents. And now, as a research scientist with NRCan’s Canadian Forest Service (CFS), he stands on the frontlines of climate change–focused research.
Based at the CFS’s Pacific Forestry Centre in Victoria, B.C., and wearing a second hat as an adjunct professor in the Faculty of Forestry at the University of British Columbia, Nicolas studies how various pathogens — from unusual water moulds to aggressive fungi — are evolving and impacting forests across Canada. Armed with seedlings, genetic tools and a long and deep love for the outdoors, he’s searching for ways to help our forests maintain their ecological balance.
We caught up with Nicolas to talk about how patience is key in forest research, what excites him about new technology and why collaboration matters in science.
What inspired you to pursue a career in forest pathology?
Nicolas Feau, forest pathologist, Canadian Forest Service.
The first thing was the forest: I’ve always been drawn to nature. I was in the forest picking mushrooms with my parents when I was five. That connection to the outdoors has always been a part of me. Forest pathology came later, almost by accident. I took a class in plant pathology at university, and I thought, “This is interesting.” Then I did a master’s program in France on the interaction between poplar trees and one of their pathogens. That was when I said, “OK, I want to be a tree pathologist.” From there, I switched into a PhD program in forest biology at Laval University in Quebec.
What makes studying trees and forests unique compared with other plant sciences?
Trees are very different because of their scale — both in the size of the plant and in the time it takes for things to happen. A forest is not like a crop field: trees take much longer to grow, and their interactions with pathogens can unfold over years, sometimes even decades. This makes the research more challenging, but also more fascinating. You have to be patient. It requires innovative approaches to study these long-lived organisms effectively.
What drew you to working with fungi and pathogens?
I’ve always found fungi fascinating. They’re really diverse and interact with trees in incredibly complex ways. Some of the pathogens I work with — the oomycetes, or water moulds, like Phytophthora ramorum — are not even true fungi: they’re filamentous pathogens closer to algae. But they can cause devastating diseases to forests, like sudden oak death. Understanding how this happens is both challenging and exciting.
What does a typical day look like for you?
Every day is different. One day, I’ll be in the field sampling soil, roots or leaves on diseased trees, and another day I’ll be in the lab conducting experiments. I might get an email from someone asking me to come look at a tree because they think there’s something wrong. I also spend a lot of time analyzing data, writing publications and mentoring students.
I feel like I’m still a student. My job is about learning every day, reading publications, learning from colleagues and learning from my experiences — both good and bad. But I still like to put my hands in the dirt. Some experiments I want to do myself because I’m excited to test an idea and see the results. I feel like I have the best job in the world — it’s never boring.
Technicians evaluate seedlings being grown to better understand which trees will be resilient to future climates and pathogens.
How important are skills like collaboration and teamwork in your work?
They’re critical. The relationship with people in the lab — technicians, students — it’s everything. I couldn’t do this work without them.
Collaboration with colleagues is just as important. These days, it’s impossible to do good work in isolation. We need to exchange ideas and get feedback. Some of the best discussions we can have with colleagues are corridor conversations. They’re casual and without pressure, but ideas circulate, and the exchange is very constructive. Someone might say, “You should consider this,” or “Maybe you should test that,” and that’s where great ideas are born.
What are some of the biggest challenges facing forests today?
Climate change is having a big impact. Pathogens that have coexisted with trees for thousands of years are now becoming more virulent because of environmental changes. The systems were balanced before: trees could resist, and the pathogens only caused minor damage. But now, with rising temperatures and changing conditions, that balance is being disrupted.
We’re also dealing with global trade, which introduces new pathogens to ecosystems that have no natural defences. For example, wooden crates used for shipping can carry fungal spores or pests across the ocean. Once introduced, these pathogens can cause serious damage to forests.
Why is this research so important right now?
We’re seeing more and more tree diseases emerging because of environmental changes. For example, in British Columbia, trees are being impacted by drought and heat stress every summer. These changes are also affecting pathogens — they’re altering their life cycles and biology, which has a cascading effect on trees.
It’s important to understand these interactions so we can predict what’s coming. That allows us to make recommendations to foresters about which trees will be resilient to future climates and pathogens.
New technologies like controlled plant growth chambers allow researchers to fine-tune conditions and standardize their experiments
What excites you about the future of forest pathology?
I’m inspired by the tools we have now — molecular biology tools and biotechnologies like gene-editing approaches, for example. These allow us to manipulate living organisms in ways we couldn’t before. For example, if I find a gene that has the potential to give resistance to a pathogen, I could validate that hypothesis in just a couple of weeks using these new tools. The traditional way would take much longer.
It’s incredible to see how these technologies are advancing our understanding and helping us find solutions to protect forests.
What advice would you give to someone considering a career in forest pathology?
Be excited. Read. Think about what you want to test, and stay passionate about it. Science is demanding. There’ll be long days, and not everything will go as planned: papers get rejected, experiments fail. But if you’re passionate, it’s all worth it.
Forest pathology is particularly rewarding because you keep one foot in the forest and the other one in the lab, and you’re working with living organisms and understanding how they interact. That’s what keeps me excited.
Explore:
To learn more, check out the CFS’s Trees, insects, mites and diseases of Canada’s forests database, which provides detailed information on over 400 insects, fungi, viruses and other damage agents that affect more than 200 native trees in Canada’s natural, rural and urban areas.