IPM Pest Biology - Weeds Module
Weeds Module – 10 hours
Cost for Session 5
$250 - registration fee
Course developer and Instructor: Dr. Erik A. Lehnhoff, Assistant Research Professor, Department of Land Resources and Environmental Sciences, Montana State University.
Session 5 Start Date: October 2012 dates to be determined.
Session 5 End Date: November 2012 dates to be determined.
A student who successfully completes the IPM3 Pest Biologies-Weeds Module will receive 1.0 CEUs and a Certificate of Completion. This information will be added to your personal portfolio so you will always know what you have completed.
This module will begin with a brief introduction to weeds and then will guide students through basic plant biology to the extent necessary to make management decisions. Students will then be presented with information regarding why weeds are invasive, what makes plant communities prone to invasion, how invasions occur and how populations spread. Subsequent materials will provide an understanding of weed vulnerability through analysis of population dynamics and focusing on plant life history stages. Finally, students will learn how different control techniques can be integrated and used to target weeds in different life stages and different phases of infestation (e.g., small starting infestations versus large, well established infestations). Students successfully completing this module will:
• Have a clear understanding of weed biology
• Understand how weed population dynamics affect their invasiveness
• Be able to identify vulnerable stages in a weed’s life history
• Obtain a basic understanding of what tools are available for weed management
• Understand how weeds are affected by management tools
Quizzes are provided at the conclusion of each lesson – an overall grade of 80 percent is required for a student to pass the Weeds Module. Since our goal is to increase your knowledge and understanding, there are no limitations to the number of times a student may retake an assessment.
Course Outline
Introduction to weeds (why we care) (0.5 hr)
• Economic impacts – reduced crop yield and quality, reduced forage, degraded land values, cost of control, etc.
• Ecological impacts – effects on native species richness and diversity, water use, trophic effects, etc.
• Sociological impacts – reduced recreation opportunities, disruption of military training activities, etc.
• Human and animal health impacts – allergies, poisonous to animals, burrs in livestock
Definition and classification of plants (1 hr)
• Life history strategies
o Annual
- Summer annual
- Winter annual (example/case study: cheatgrass)
o Biennial
o Perennial
- Herbaceous perennial
- Rhizomatous herbaceous perennial (example/case study: yellow toadflax)
- Woody plants
• Evolutionary strategies
- Ruderal
- Competitor
- Stress tolerator
Photosynthesis and nutrient uptake (0.5 hr)
• Water acquisition
• Nutrient acquisition
• Vascular system (movement of water and carbohydrates)
Reproduction (1.5 hrs)
• Sexual (pollination and seed production)
• Asexual (clonal growth)
• Seed dispersal
o Physiological and morphological adaptations
o Primary dispersal
o Secondary dispersal
• Seed dormancy
• Seed germination
o Abiotic requirements
o Biotic requirements
Genetics and evolution (0.5 hours)
• Implications of high genetic variability
How plant invasions occur (2 hr)
• Intrinsic factors (traits of invasive weeds)
o Life history traits
o Native geographic range
o Release from natural enemies
o Evolution of increased competitive ability
o Ecological amplitude
• Extrinsic factors (what makes a plant community susceptible to invasion)
o Disturbance
o Resource availability
o Richness
• (Example/case study: predicting weed invasions based on intrinsic & extrinsic factors)
Stages of weed invasion (1 hr)
• Introduction
• Lag phase of population growth
• Exponential phase of population growth
• Naturalization
• Population spread
o Sources and satellites
o Advancing front
• (Example/case study: simulation of spread with population and habitat model)
Population dynamics and life history analysis (1 hr)
• Why models are useful for management
• Simple population growth calculation
• How to construct a simple model
• (Example/case study: leafy spurge)
Introduction to PAMS Approach and Weed Management Tools (2 hr)
• Prevention – pest-free seeds/transplants, eliminate weed reproduction, irrigation schedule, equipment cleaning, border protection, etc.
• Avoidance – crop rotation, minimizing weed establishment sites, maintain native species diversity, etc.
• Monitoring – survey programs, record keeping, etc.
• Suppression
o Cultural – crop/native species competition, mulches and cover crops
o Physical – hand pulling/hoeing, burning, tillage, mowing, chaining, flooding, mulches and solarization
o Biological – grazing, conservation of natural enemies, classical biocontrol, inundative strategies
o (Example/case study: Knapweed biocontrol video)
o Herbicide – when to use (cost/ecological thresholds), classification, selectivity, resistance problems and management, calibration, managing off-target impacts
If you are interested in completing this course, please contact us at ipm3@umn.edu with your contact information and approximate date range that you would like to complete the course.
