Plants are nature’s master chemists; they deploy complex networks of specialized metabolites to interact with other organisms and adapt to their environment. Among these metabolites, terpenoids encompass the largest class with critical functions in plant development, chemical ecology and stress adaptation. Their chemical diversity also offers a rich source for bioproducts, including flavors, fragrances, pharmaceuticals and more. A deeper understanding of the diversity, regulation and function of plant terpenoid metabolism could offer innovative avenues toward agricultural and other industrial applications. Toward this vision, the Zerbe Lab integrates functional genomics, metabolomics and various protein biochemical and genetic approaches to investigate the biosynthesis, regulation and function of terpenoids in food, bioenergy, and medicinal plants. We will report on the discovery of common and species-specific terpenoid pathways in maize and switchgrass that provide core components of chemical defenses against biotic and abiotic stressors.