For the InstructorThese 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.
Interpreting a 12-year Summary of Crop and Soil Management from New York
Review the Crop and Soil Management Research 12-year summary from New York shown in the table below; then answer the questions listed below.
Five cropping systems were applied for 10 years (1935-45) to the experimental treatment fields and one field was left idle (not cropped or harvested, fallow). Soil erosion was measured over the ten years, and at the end of the 10 years, soil organic matter and aggregation were measured in each treatment. A crop uniformity test was also conducted: corn was produced on all of the treatment fields for two years. Assume that the same tillage equipment was used to plant all of the crops. The table summarizes a number of cropping systems performance indicators: i. soil loss over the 10 years, ii. average corn grain yields in the two years after the 10 years or cropping system history, iii. the percentage of soil organic matter and iv. the percentage of soil aggregation.
- Based on what you have learned about how crop types and tillage influence soil, how do you interpret and explain the soil loss, soil organic matter and aggregation differences among the six cropping system treatments? Consider which crops are annuals, biennials, and perennials, and how crop life history and planting frequency can affect soil conservation and quality. Explain your answer.
- How do you explain the differences in the corn grain yields following the 10 years of the cropping system treatments? Consider how the crops cultivated for the 10 years influenced the three soil quality indicators. In addition, consider how the different previous crops might have influenced other factors that can affect corn yield. Explain your answer.
- Based on what you have learned about crop and soil management practices, are there other crop and soil management practices that may not have been implemented that could improve soil health and agroecosystem performance? Explain two other approaches you would recommend, why, and how the approaches would improve soil health and agroecosystem performance.
|Soil Management (1935 - 45)||Total Soil Loss (1935-45) T/ha||Corn Grain Yields (1946-47 avg.) Kg/ha||Soil Organic Matter %||Soil Aggregation %|
|Idle field (not cropped or harvested: fallow)||4||4930||4.6||86|
|Perennial meadow (grazed or harvested perennial grass and legume crops) fertilized‡||0||4770||4.5||83|
|Rotation, potatoes-sweetclover (biennial clover)||29||3770||4.1||75|
|Corn-oats-perennial clover rotation (fertilized) §||7||3490||4.7||79|
|Corn, continuous (fertilized)†||76||1880||3.1||67|
|Corn, continuous (unfertilized)||108||1570||3.0||68|
Data selected and annotated from W. Reid, 1985. In Soil Erosion and Crop Productivity, Ed. R. F. Follett and B.A. Stewart, ASA, Madison, WI. p. 245
† Corn fertilized with 112, 49, and 9.3 kg/ha of N, P, and K, respectively, worked into the plow layer during 1946 and 1947. Lime was also mixed into the plow layer during 1946.
‡ 13.4 t/ha farm manure + 47 kg/lha P once every 3 years + lime.
§13.4 t/ha farm manure + 21 kg/ha P before corn + 21 kg/ha before oats + lime before clover.
Download the worksheet (Microsoft Word 2007 (.docx) 105kB Jan3 18) to complete and turn in your assessment.;
Submitting your assignment
You or your partner should submit one set of answers for the two of you in your course LMS. Bring your typed answers to this assessment to the following class for discussion.
Scoring and Rubric
This assignment will earn a maximum of 36 points, as described in the rubric below.
|Answers should clearly explain how the cropping systems influence soil loss, organic matter and aggregation should be clearly explained with reference to Module concepts. Answers should discuss the different impacts of the prior crops. (5 points for each soil metric). Points will be deducted for incomplete or inaccurate answers.||15|
|Analysis should explain how the different types of cropping systems and their impact on agroecosystem factors, and the 3 soil health properties likely contributed to differences in corn crop yield with reference to the Module concepts.||10|
|Crop and soil management practices prescribed should be appropriate to improve soil health and agroecosystem performance. Answers should accurately interpret how the approaches could potentially improve soil health and agroecosystem performance.||6|
|Answers are grammatically correct and well organized.||5|