Justin’s research focuses on the chemically mediated ecological interactions between plants and herbivores. His current research includes: (1) exploring chemically-mediated ecological interactions between invasive plants and herbivores to improve biocontrol as a management tool, (2) examining how bark beetle attack alters tree chemistry and how this affects flammability to better predict and manage wildfires, and (3) investigating the roles plant volatiles play in plant-pollinator interactions and how herbivory and invasive plants alter these interactions at the community level. Justin also researches the taxonomy and biodiversity of long-legged flies (Diptera: Dolichopodidae).
Biological control is one of the few tools capable of managing widespread exotic plant invasions, which, at its most successful, can offer long-term solutions to weed problems. However, some biological control agents obtain approval and are released, but fail to impact weed populations. This is troublesome because exploration, testing, and approval for each agent take many years and is estimated to cost several millions of dollars to complete. Moreover, ineffective agents can persist and cause unwanted ecological changes in the communities in which they occur. A better understanding of the interactions between biocontrol agents and their invasive host plants is needed to identify the factors which promote or limit successful biocontrol. My approach is to apply the chemical ecology of plant-herbivore interactions to classical biological control of weeds - two fields which have largely progressed independently to date. Chemistry plays a central role in determining ecological outcomes between plants and insects, and should provide information that can be used to better predict which potential agents are most likely to be effective.
importance of research
Invasive species present one of the greatest threats to the health and sustainability of ecosystems worldwide. This research will better position us to devise and apply biological control to address plant invasions. It will also advance our basic understanding of the ecology of plant-insect interactions and the conditions under which herbivory translates into meaningful changes in plant populations - fundamental ecological questions that hold great promise for managing invasive plants.
1. Chemical Ecology of interactions between invasive parasitic plants, their host plants, and insect herbivores. 2. Biological control and chemical ecology of the tritrophic system consisting of the wheat stem sawfly, host plants, and natural enemies.3. Taxonomy and revisionary studies of long-legged flies (Diptera: Dolichopodidae).