Module and Case Study examples describe specific practices related to principles explained in the text of the 4R Plant Nutrition Manual, or provide background information supporting the principles. While modular examples aim to provide experimental data or specific technical information related to the scientific principles discussed, case studies aim to describe situations in which the application of scientific principles related to nutrient stewardship has helped to resolve issues. These case studies may range in scale from a field or farm to regions or watersheds. You can access all of the available Modules and Case Studies from the Chapter links provided below.