With the advent of widespread use of commercial fertilizers in the 1950s and 1960s, sampling the soil to establish a nutrient level was needed to make an application recommendation, just as today. Initially, a number of cores were taken randomly throughout the field. Fields were much smaller then and any nutrient information was a great improvement over no information at all. Even though nutrient differences in the field were observed, there was no system to vary the fertilizer rate for those differences.
The whole field composite method remained even when fields increased in size. There are many reasons why whole field composite sampling still is practiced, although it is neither precise nor repeatable. To ensure the highest quality of sample results, MISS does two things:
- MISS samplers avoid taking cores at non-representative parts of the field such as eroded knolls, headlands, close to waterways, etc…
- To accomplish the true average, core spacing is set as equidistantly apart as possible. MISS uses the same computers and GPS systems that are used for grid or zone sampling. Years of experience tells us that even spacing of cores on whole fields is not possible by sight from the seat of an ATV or pickup.
Typical soil sample core.