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St. Louis, Missouri


InfoAg 2018 Presentation
Zones vs. Grid

Regency C
Wed, Jul 18, 2018
8:40am to 9:20am

Zones vs. Grid

Regency C
Wed, Jul 18, 2018
2:00pm to 2:40pm

Do We Have Soil Test Recommendations Precise Enough to Support Precision Agriculture?

Soil testing encompasses the process of collecting soil samples, having them analyzed, and then interpreting the results to make fertilizer recommendations. This process attempts to provide information on the amount of nutrient present and its availability to the crops. We should soil test at a spatial resolution matching that of our nutrient application. We typically determine this resolution based on equipment capabilities and the size of zones within a field that can be managed uniformly. However, we typically focus on collecting soil samples at the appropriate resolution, through zone or grid sampling, but ignore the resolution at which scientists developed recommendations. We will discuss soil test correlation and calibration, the resulting recommendations, and the need to update recommendations to support site specific nutrient management.


Josh McGrath

Associate Professor & Extension Specialist
University of Kentucky