Integrated Weed Management for Agribusiness Professionals
(Integrated Weed Management in Field Crops)

Weeds flamed in Agriculture, weed management, invasive plant management

Spring 2020: February 17-May 8

Offered Spring 2020 (even-numbered years)

Instructor: Dr. Stevan Knezevic

Class Number:  AGRO/HORT 822

Credits: One graduate credit/one Plant Breeding & Genetics professional certificate unit

Certified Crop Advisors (CCAs) taking this course for academic credit may earn six Continuing Education Units (CEUs) in Pest Management.

Please self-report your Certified Crop Advisor (CCA) CEUs from the graduate class at


Academic Credit register through MyRed

Professional Credit (Non-academic) Registration


This is a true web-based class as the sessions are recorded and archived on eXtension or Canvas. Lectures will be available once the semester starts.

Integrated Weed Management (IWM) in Field Crops will be offered during spring 2020. A follow-up to this course is in development (IWM of Invasive Species) and is likely to be offered during the Fall of 2020.

Both courses are designed to provide graduate students and agribusiness professionals engaged in production agriculture with a working understanding IWM principles as a basis for understanding weed control issues in both conventional and organic cropping systems. IWM, which is based on a multidisciplinary approach to weed control, provides information on the need for and timing of weed control, the effective and environmentally sound use of herbicides, and alternatives to herbicide use, such as weed flaming.

A single weed control measure is not feasible due to the number of different weed species and their highly diverse life cycles and survival strategies. In addition, control practices based on only one method give weeds a chance to adapt to those practices. Weed resistance to herbicides is a perfect example of weed adaptation.

Historically speaking, repeated use of atrazine-based herbicides in the 1970s and 1980s resulted in triazine-resistant weeds. Then, repeated use of ALS herbicides (Pursuit, Scepter, Raptor) in the 1990s resulted in ALS-resistant weeds. Finally, repeated use of glyphosate-based products between the early 2000s and today, resulted in the development of glyphosate resistant weeds. Apparently, history repeats itself, and unfortunately, we have not learned the lesson.

Dr. Knezevic said that development of an IWM program should be based on a few general principles that can be used at any farm including: (1) using agronomic practices that limit the introduction and spread of weeds (preventing weed problems before they start), (2) helping the crop compete with weeds (help “choke out” weeds), and (3) using practices that keep weeds “off balance” (do not allow weeds to adapt). Therefore, this class is designed to provide working understanding of IWM principles in both conventional and organic cropping systems.

Topics covered during the course include:

  1. IWM - introduction and overview
  2. Weed biology, growth and ecology
  3. Critical periods of weed control
  4. Weed thresholds
  5. Weed shifts
  6. Benefits, concerns and risks with herbicide tolerant crops
  7. Weed resistance
  8. Developing your weed control program


Academic students are expected to complete Internet/Canvas-based assignments and quizzes and participate in an online discussion board.


None.  All materials will be made available via the Internet through Canvas or eXtension.


High-speed Internet access, email, updated browser and ability to view videos.


Individuals taking the course for academic credit must be enrolled in UNL's Graduate School and have completed 12 hours in agronomy or closely related biological sciences courses.


Academic Credit Course: For information on tuition and fees, visit the Student Accounts website.
Professional Credit (non-academic): Course fee is $270 per credit hour.

Who It's For

Among those who would benefit from this course are:

  • Graduate students, preparing for more intensive or specialized study later
  • Certified professional agronomists and crop consultants: Certified Crop Advisors (CCAs) taking this course for academic credit may earn six Continuing Education Units (CEUs) in Pest Management.
  • Crop production and pest management industry personnel
  • Producers
  • Individuals interested in incorporating IWM into organic farming practices
  • Extension educators
  • Science and vocational agriculture teachers