I am a historian, specializing in the environmental history of tropical crops. I teach in the history department at the University of Guelph, a vibrant comprehensive university located in the lovely city of Guelph, short drive west of Toronto, Canada. My first book, States of Nature: Science, Agriculture, and Environment, 1760-1940, focused on the origins of the plant sciences in the Spanish-speaking Caribbean. Since then, I have done research on the environmental history of cacao cultivation, and most recently on the environmental history of coffee cultivation. In both cases, I have been particularly interested in the origins and impact of plant pathogens on these tropical commodities. I’m currently writing a global history of the coffee rust epidemic, caused by the fungus Hemileia vastatrix. Many of my publications are available for free download at my academia.edu website.