Fall (alternate years, even); Aug 24 - Dec 15, 2022
Credit: 3 graduate 
Instructor(s): William Dyer, Tracy Sterling, Sarah Ward

Course Description

PSPP 546 Herbicide Physiology is a distance delivery graduate course to be offered in Fall semesters of even-numbered years (next offering 2018).  We will cover topics in herbicide classification, herbicide mode of action, resistance mechanisms, and practical diagnosis of field situations. Prerequisites include upper division courses in biochemistry and plant physiology, or consent of the instructors. The course is designed for students without traditional access to this course material, and is not designed to replace existing, on-campus courses at other institutions.

Meeting Place and Times

Participants login to the course at a time of day that best fits their schedule. It is necessary to connect at least 4 - 6 times per week and spend at least 8 - 10 hours per week while the course is in session, either online or offline working on course related assignments, to stay current and successfully complete this 3 credit graduate course.


William Dyer. Professor, Plant Sciences and Plant Physiology, Montana State University.  Ph.D. 1988, Purdue Univ. Research interests include physiology and molecular biology of seed dormancy maintenance and release in Avena fatua; Biochemistry and molecular biology of evolved resistance to herbicides; Population genetics and spatial components of invasiveness in Kochia scoparia. 

Erin Burns Crop & Soil Sciences, Michigan State University.  Dr. Burns is an Assistant Professor in the Department of Plant, Soil, and Microbial Processes.  Her research and extension program focuses on current and emerging problematic weeds in Michigan cropping systems. Current research is focused on biology, ecology, population dynamics, and integrated weed management of problematic weeds with emphasis on practices to mitigate the development and spread of herbicide-resistant weeds.

Dean Riechers Agronomy, University of Illinois

Tracy Sterling, Professor and Department Head, Land Resources and Environmental Sciences, Montana State University. Dr. Sterling received her Ph.D. 1988 in Agronomy with Botany Minor, University of Wisconsin - Madison; M.S. 1985 in Horticulture, Michigan State University; B.S. 1983 in Horticulture and Agronomy, University of Minnesota. Reserch interests include weed physiology research centering on understanding how environmental, insect, and herbicide stresses influence crop and weed productivity. Emphasis on role of oxidative stress tolderance mechanisms in weed/crop interactions, and alkaloid biosynthesis by the locoweed/endophyte complex. 

Sarah Ward, PhD. Sarah is Associate Professor of Plant Genetics in the Department of Soil and Crop Sciences at Colorado State University, and a Faculty Affiliate in the Department of Land Resources and Environmental Sciences at Montana State University. She is also Director of Publications and a member of the Executive Committee of the Weed Science Society of America. A former plant breeder, Dr. Ward’s research now focuses on the genetics and population biology of weedy and invasive plants. Dr. Ward’s current research projects include the dynamics of herbicide resistant weed populations in dryland cropping systems, and impacts of gene flow on the spread of invasive toadflax in the Rocky Mountains.


Upper division courses in biochemistry (BCHM 340 General Biochemistry or equivalent) and plant physiology (PS 450 Plant Physiology or equivalent), or consent of the instructors. Contact Dr. William Dyer at for more information.

Target Audience

Students from Weed Science, Plant Physiology, Plant Biology, Land Reclamation, Ecology, Range Science, Agronomy, Integrated Pest Management, and Conservation Biology will be served by this course. In addition to providing basic information about herbicide physiology and plant responses, we will challenge students with applied problems that may be encountered in field situations. Students will thus be able to hone their diagnostic and problem-solving skills that will be required in a number of employment situations.

Time Commitment:

9-12 hours per week. If you are unfamiliar with this field of study and/or method of delivery, you may require more time.

Tuition and Fees

See the Online Tuition, Fees and Financial Aid page.

If you are also taking a face-to-face course, please refer to the MSU Fee Schedules.

Required Books/Materials

  • This course has no textbook as all readings and activities take place online.

Computer Requirements:

  • Internet access
  • A device and browser that pass the system check for Brightspace LE, MSU's learning management system.

This course uses a learning management system. You will learn more closer to the course start date.

For More Information

Contact Dr. William Dyer at

How to Register

You must be accepted as a student to Montana State University to take this course.

Learn how to apply.

After your application has been accepted, you will register via MSU's online registration system, MyInfo.

Registration requires a PIN number. Learn how to find your PIN.

Once you have your PIN, learn how to register through MyInfo.