Fundamentals of weed biology; cultural and chemical weed control; properties and uses of herbicides and herbicide application equipment; and current systems for weed management in cropping programs.
Additional Requirements for Graduate Students: A term paper will be required of graduate students.
Athena Title
Weed Science
Equivalent Courses
Not open to students with credit in CRSS 4340E or CRSS 6340E
Undergraduate Prerequisite
BIOL 1103 or BIOL 1107 or [PBIO(BIOL) 1210 and PBIO(BIOL) 1210L]
Graduate Prerequisite
BIOL 1103 or BIOL 1107 or [PBIO(BIOL) 1210 and PBIO(BIOL) 1210L]
Semester Course Offered
Offered fall
Grading System
A - F (Traditional)
Student learning Outcomes
Students will be able to identify problem weeds in row crop, non-crop, and turf situations.
Students will understand how extension specialists and research personnel are applying the principles of weed science to solve weed management problems.
Students will understand new technologies for solving weed management problems.
Topical Outline
Section 1: Why are we Concerned with Weeds?
A. What is a weed and what are characteristics of weedy plants?
B. What are the types of losses (agronomic, environmental, economic, aesthetic, human/animal safety) caused by weeds?
C. How do weeds change the way humans interact with the environment?
Section 2: Basic Weed Biology
A. What biological characteristics allow weeds to occupy specific environmental niches?
B. What are the various weed life cycles and morphologies?
C. What classifies a weed as noxious/invasive and how does this affect management and environmental impact of this species?
D. How do weeds disperse and what role do humans play in weed proliferation?
E. What is a weed seed bank and what factors are important for weed seed dormancy and germination?
Section 3: Methods of Weed Control
A. What are cultural ways in which to prevent the introduction, establishment, and spread of a weed species to a new area?
B. What are examples of chemical, biological, non-chemical weed control and what are the agronomic, economic, and environmental impacts of using this type of weed management strategy? How can these be utilized as part of an integrated weed management approach?
C. What are the broad categories of herbicides and application methods?
Section 4: Herbicide Behavior in Soil
A. What are the major processes affecting environmental fate of herbicides in the soil?
B. What are the major soil factors that affect herbicide efficacy and environmental fate of an herbicide (absorption, adsorption, and leeching)?
C. How does herbicide physiochemistry affect the behavior of herbicides in the soil?
D. What are the major processes by which herbicides degrade in the environment?
E. What are best management practices and situations to avoid limiting the off-target movement of pesticides into the environment?
N. Unknown mode of action
Section 7: Herbicide Resistance and its Management
A. How have humans contributed to the development of herbicide resistant crops and
weeds?
B. How are resistant weeds changing the way in which humans have to manage weeds in
crop and non-crop areas?
Section 8: Weed Management Across Cropping Systems
A. Pastures and rangeland
B. Rights of way
C. Aquatic environments
D. Small grains
E. Vegetables
F. Cotton
G. Corn
H. Peanuts
I. Turfgrass
J. Nursery crops
K. Organic systems
L. Perennial crops
Section 5: Herbicide Behavior in Plants
A. What factors affect absorption, translocation and metabolism of herbicides?
B. What is the fate of an herbicide once it’s applied to a plant?
C. What ways/factors can herbicides be “safened” to protect sensitive crops?
D. Describe the differences in pesticide interactions within the plant.
Section 6: Herbicides and Their Characteristics, Uses, and Modes of Action
A. Herbicides inhibiting acetyl CoA carboxylase
B. Herbicides inhibiting acetolactate synthase
C. Herbicides inhibiting photosynthesis of photosystem II
D. Photosystem I electron diverter
E. Herbicides inhibiting protoporphyrinogen oxidase
F. Herbicides inhibiting carotenoid biosynthesis
G. Herbicides inhibiting EPSP synthase
H. Herbicides inhibiting glutamine synthetase
I. Herbicides inhibiting microtubule assembly
J. Herbicides inhibiting cell division
K. Herbicides inhibiting cellulose biosynthesis
L. Herbicides inhibiting lipid synthesis
M. Synthetic auxins
