Troy is a lichenologist, forest ecologist and conservationist. He is a researcher at the University of Guelph in the Department of Integrative Biology, where his research program is focused on conservation. The model organism he uses in the majority of his research is lichen. Troy specialises in this taxon because it is particularly useful for explaining the mechanisms underlying most of his research questions.
He has published extensively in academic journals and public media. His latest co-authored book was recently released by the New York Botanical Garden Press, Common Lichens of Northeastern North America: A Field Guide.