For the Instructor
These student materials complement the Future of Food Instructor Materials. If you would like your students to have access to the student materials, we suggest you either point them at the Student Version which omits the framing pages with information designed for faculty (and this box). Or you can download these pages in several formats that you can include in your course website or local Learning Managment System. Learn more about using, modifying, and sharing InTeGrate teaching materials.Formative Assessment
Part 1: Australian grain crop IPM
Watch the following video that explains IPM adoption in grain crops in Australia; then answer this question:
1. Identify and explain three benefits of utilizing IPM discussed in the Australian video from the GRDC.
Video 1: GCTV2: Integrated Pest Management (5:46)
If the video does not load for you, go to GCTV2: Integrated Pest Management
Part 2: Determining the Economic Threshold of Potato Leafhoppers in Alfalfa
Read the Penn State University Potato Leafhopper on Alfalfa Fact Sheet.
Credit: Penn State University Potato Leafhopper Alfalfa Fact Sheet
Scenario
Assume that you followed the procedure described in the Penn State fact sheet to scout for Potato Leafhoppers in an alfalfa field by sweeping 20 times with your sweepnet in each of 5 different locations in the alfalfa field. The number of leafhoppers that you found in the 5 different locations was: 15, 12, 16, 7, 13, when the alfalfa crop was about 11 inches tall. You would like the alfalfa to grow about 25-30 inches height before harvesting it for hay, this could require 2 to 3 more weeks of growth, depending on rainfall. Based on current alfalfa hay prices in your region, you estimate your alfalfa hay is worth about $250/Ton, and the insecticide you would spray to control the leafhoppers would cost about $16/A. If you spray the alfalfa field, it cannot be harvest until 7 days after spraying the insecticide; and due to toxicity to bees, the alfalfa should not be sprayed if it is flowering.
Answer the following questions:
- Calculate the average number of leafhoppers per sweep. Add the number of potato leafhoppers from the 20 sweeps in each of the 5 locations (20 X 5= 100 sweeps). Divide by 100 to calculate the number of leafhoppers per sweep. Use the Economic Threshold Table from the Fact Sheet for Potato Leafhoppers, shown here. Has the insect population reached an economic threshold for your crop at this height?
- Based on the average number of leafhoppers per sweep, what should you do? Why?
- If your crop height was 7 inches tall and you had the same number of leafhoppers per sweep that you calculated here, would your pest management decision change and how?
- Discuss at least two potential benefits of using the economic threshold decision tool rather than spraying as soon as potato leafhoppers were first visible.
Files to Download
Module 8.1 Formative Assessment Worksheet (Microsoft Word 2007 (.docx) 94kB Jan3 18)
Submitting Your Assignment
Please submit your assignment through the LMS.
Grading Information and Rubric
This assessment is worth a possible 30 points.
Description | Possible Points |
---|---|
Students should distinguish, three specific benefits of IPM methods from the Australian case study. Answers should refer to and explain specific module IPM concepts. Clear, well written and organized answers will receive full credit, points will be deducted for weak writing and explanations. | 9 points |
Questions about the economic threshold answers should be accurate and reflect and understand how to interpret the economic threshold and decide what action to take at different states of crop development. Answers should be accurate, clearly explained, and refer to IPM and module concepts (5 points each). Clear, well-written and organized answers will receive full credit, points will be deducted for weak writing and explanations. | 15 points |
Answers should discuss two benefits of applying IPM for alfalfa potato leafhopper control and draw on concepts discussed in this module. Clear, well-written and organized answers will receive full credit, points will be deducted for weak writing and explanations. | 6 points |