Among the numerous challenges of crop production is the management of soil nutrients, soil moisture content and crop and soil variability. One of the first problems that was addressed in precision agriculture was site-specific nutrient management (Pierce and Nowak, 1999). Since then, advancements have been made in the creation of mathematical approaches that can be used to help match fertilizer recommendations to soil and crop productivity. This chapter will review sources of soil variability and current management tools and techniques to help growers manage soil variability.

Powerpoint