As the combines mark the end of one crop, they also welcome the beginning of the next. Decisions made at this point will affect a farms direction over the season to come. So, it’s worth spending a little time evaluating what went well, what can be improved and how to adjust. Hopefully this planning will save time, money and maybe even a little aggravation.
“What is a composite, zone or grid soil sample?” This is one of those questions that should be asked during the planning stages. When understood, it lets you select a technique that will be most effective for your fertilizer application. Knowing the techniques and when to use them, allows for an educated decision; one that will affect the crop all season long.
The images do a nice job of showing the techniques, but below is a little more explanation.
Composite sampling has been around for years and management zones in their simplest form are basically refined composite samples. For decades universities have taught to divide fields into like areas, then pull a set of soil cores that best represent those areas.
Today we are using new technologies to define those like areas. We call them management zones. The philosophy surrounding management zones has been preached for decades, we are just refining the technique.
Grid Samples on the other hand make no attempt to define like areas. Instead you are pulling a set of soil cores in a very small area around a specific GPS point based on a set grid pattern of consistent size. Those samples are then fed into a statistical model that does its best job of estimating what the values between the samples should be.
The number of samples and how the samples are taken affects the fertilizer recommendations, and the fertilizer applications affect the crop for the entire season. Give it some thought, so you can choose the appropriate soil sampling technique for your operation and capabilities.
Want to learn more about these techniques? To explore grids and zones for creating fertilizer recommendations, be sure to visit Precision Ag Services.
Written by: Nathan Woydziak, Hoisington, KS