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EPA Liaison


Dr. Mark VanGessel

Professor and Extension Specialist
University of Delaware
Carvel Research and Education Center

16684 County Seat Highway
Georgetown, DE 19947
E-mail: [email protected]
Phone: 302-856-7303

The WSSA’s EPA Liaison position is a partnership between WSSA and the Environmental Protection Agency’s (EPA) Office of Pesticide Programs (OPP). The Board of Directors designated the position as Academic Subject Matter Expert (SME) in May, 2007. The first EPA-SME was Dr. Steve Dewey, Utah State University. Dr. Jill Schroeder, New Mexico State University, replaced Steve in 2008 and served four and one-half years in the position.  Following Dr. Schroeder, Dr. Michael Barrett, University of Kentucky, served in this position between 2013 and 2017. Dr. Greg Kruger, University of Nebraska followed Dr. Barrett. Dr. Mark VanGessel, University of Delaware is the current EPA-SME.

The vision for this position is to develop a liaison between the academic Weed Science community and the EPA in order to assist the Agency in addressing crop and noncrop weed control issues that directly impact the weed management practitioner. The person serving in this role travels to the EPA Headquarters every 4 to 8 weeks to work in the offices of the EPA-OPP.  During these visits, the individual interacts with EPA employees and provides input on a wide range of topics such as current weed management practices, the utility of label mitigations for herbicide use, herbicide resistance management, spray drift management, weed and invasive plant management near endangered species, and the role of weed control in land management.  In addition to working directly with EPA-OPP staff, the EPA-SME facilitates connections between EPA and others in the weed science community as needed to address herbicide registration questions.  The EPA-SME also arranges weed science educational activities, such as seminars and field tours, for the EPA-OPP employees.

Beyond serving as a weed science resource for the Agency, the EPA-SME learns the registration and re-registration processes for herbicides, becomes familiar with the EPA scientific committees and how they operate, and develops a basic understanding of how EPA-OPP risk assessments are conducted.  The EPA-SME communicates this knowledge to the weed science community on a regular basis through presentations at annual meetings and through other means such as the preparation of a quarterly report for the WSSA Board of Directors and for posting on the WSSA website. WSSA welcomes Dr. VanGessel to EPA-SME role to continue and build on the relationship between EPA and WSSA for their mutual benefit.

Note: Quarterly reports to the WSSA Board and other reports are available on the right-side bar

EPA Liaison Reports to the WSSA Board

  • EPA Staff Update
  • Recent Activities
  • Webinars
  • Upcoming / Future Activities

Other Reports