I am involved in a range of collaborative studies with the overall objective of assessing and improving the efficacy and safety of classical weed biological control. One of my ongoing studies to further understand shortfalls in realized biological control of exotic toadflax will determine if toadflax biocontrol agents exhibit differential responses to yellow x Dalmatian toadflax hybrids vs. either of the parental toadflax species. The recently confirmed hybridization of these exotic weeds under field conditions potentially affects agents both behaviorally (in terms of host location and acceptance) and biologically (in terms of reproductive success). I am developing a host plant test list and participating in host selectivity testing with members of the North American Toadflax Consortium to identify and gain approval for the release of one or more new yellow toadflax biocontrol agents. Much of my research is undertaken to parameterize comparative ecological risk assessments for selecting optimally safe and effective invasive weed management strategies. I am also involved in long-term monitoring projects, including ecological and biocontrol studies on saltcedar, and evaluating the potential for integrating herbicide treatments and biological control of Dalmation toadflax on prescribed burn treated rangeland. New studies will focus on potential effects of climate change on weed biocontrol efficacy, identifying and evaluating biocontrol agents for Russian olive and oxeye daisy, and surveying and evaluating the ecological impacts of aquatic weeds to assess their potential as classical biological control targets.
Insect-plant interactions influencing and influenced by invasive species is the common theme running through my research.
Classical weed biological control can be a cost-effective, sustainable and ecologically sound way to manage exotic invasive weeds. Unqualified weed biocontrol success stories are, however, altogether too rare. Developing, using and teaching methods for quantitatively evaluating the impact of biocontrol treatments will increase the documentation of successful releases when it does occur, and will satisfy currently unmet planning needs. Post-release monitoring is ethically critical to ensuring accountable management of public lands and resources; monitoring is truly the only way to detect negative outcomes such as treatment failures and shortfalls, and nontarget impacts. Coordinating and participating in the search for and testing of new weed biocontrol agents based on stakeholder needs will increase weed biocontrol implementation. Basic research focused on insect-plant interactions will continue to improve the safety of this management tool, and identify biological and ecological impediments when control shortfalls occur.
1. Co-investigator on a collaborative project confirming naturally-occuring hybridization of yellow and Dalmatian toadflax; many ongoing and planned studies have built on this discovery. 2. Ecological risk assessment: collaborator on a number of studies that will be used for evaluating risks associated with invasive weeds and management approaches for those weeds. 3. Co-author of several technology transfer publications on the management or biological control of specific weeds: yellow toadflax, Dalmatian toadflax, houndstongue, tansy ragwort, and saltcedar.