Soil Sampling in the Fall


We found a great article on Ag Anytime about soil sampling in the fall and wanted to share it with our followers. Soil sampling is one of the most important things our team does in the fall after harvest every year to ensure that we are keeping diligent records of our soil health. Records kept from year to year can give you a in-depth look at what works and what doesn’t. Fall is the best time to take a soil sample to yield the most accurate results. Here is a brief recap of the Soil Sampling article from Ag Anytime, but you can read the full article here.

  1. Timing. Fall is the most practical time for soil sampling – right after harvest – since the winter or too early in the spring made yield misleading results. Late spring also gets to be a busy time preparing for planting. That’s why October-November after harvest is the optimum time to test your soil. We recommend taking soil samples every year, at the same time each year, and keeping diligent records of your soil. Nutrients in your soil are greatly affected by environmental conditions and the seasonal variation should be accounted for when collecting samples.
  2. Patterns. There are three different kinds of sampling patterns you can use – single, grid, and management zones.  Each of these will have a different number of samples required and will effect the precision of soil test results. A single sample is the least expensive option and you will only choose one area of a field to analyze every year. Grid sampling divides a field into individual squares or rectangles of equal size and you take a sample from each grid. GPS is used to get the most precise results and also keep records very diligently from year to year.  A management zone is an area that is managed in a similar fashion and differs from other management zones within a field including – soil type, soil slope, organic matter, and yield – among others. Soil samples are collected at random from within each zone, bulked together, and analyzed to provide an average sample value for each unit.
  3. Results. Soil testing should be repeated at the same locations to track fertility and pH changes over time. Differences in soil test results can help explain field variability. The patterns of high and low soil property values may be tied to soil type or slope or they may help explain yield variability. Interpreting the variability in soil test values takes careful research, but can lead to directing your future crop management practices.

All in all, the timing, pattern, and what you do with the results are all important aspects of soil samples. The investment in soil tests is a great opportunity to learn the best management practices for your field.