Precision Ag: Now, Not the Future.
GPS: WAAS, Coast Guard and RTK
Variable Rate Prescription Maps
As Applied Mapping
Yield Monitor Setup and Calibration
Yield Map Processing
What is Precision Ag?
Precision Ag is the 1) Collection of Data, 2) the Analysis of Data, 3) Drawing Conclusions from the Analysis, 4) Assigning a Value to those Conclusions and then, 5) Implementing an Action base on the Value of the Conclusions.
Precision Ag (PA) is farm management technique that is used to more precisely apply decision making in the input process to enhance efficiency and profitability. Benefits of PA may include reduced inputs, enhanced productivity in crop yields and time management, better decision making and enhancements to the environment.
PA is not the use of technology; it is far simpler than that. Technology greatly aids in PA but it is not the beginning of any PA program on your farm. Famers for years have done PA without the aid of technology. We need to look no further than our grandfathers for examples in the past or look to the Pacific Rim for our time to see PA used without fancy technology.
PA is a management tool in the farm management tool box. It might be a new shiny cordless impact wrench or it might be an old oxidized box end wrench, but it is just a tool; a tool that we need to learn how to use properly no matter its age.
PA is not just Global Positioning Systems (GPS); it is far greater than that. While GPS might help guide our PA decision process many farmers can do PA without the aid of computers and GPS, and have done so for years. GPS allows for precise position reports to computers and controllers that allow for the adjustment or control of the various technologies used in PA.
Variable Rate Technology (VRT) is the use of computer generated maps to automatically adjust a control device on a planter, spreader or sprayer to vary the applied target rate of seed, fertilizer or chemicals. Many farmers have done variable rate (VR) in the past without the aid of computers or controllers by simply applying the target rate where it was needed and manually changing the rate where more or less was needed. VRT allows for the “on the go” change of these targets without having to stop to make a manual adjustment.
One myth of VRT is the need to Grid Soil Sample. Grid Sampling is not PA and is not the basis to start a PA program on your farm. Grid Sampling is one of many methods of collecting soil samples to determine soil fertility. One does not have to change their soil sampling pattern to create nutrient management maps for variable rate application. VRT can be done using already existing sampling patterns or zones, soil types, or management zones.
Another myth is that Grid Soil Sampling is relatively new; developed in the 1990’s as a benchmark or basis for the PA movement and requires GPS and computers for use. Again there is nothing new or revolutionary about Grid Sampling. It has been around since the 1930’s and even VR application with color coded maps came about at the same time. The University of Illinois even published, in 1929, a pamphlet on how to Grid Test and make VR maps, long before GPS, computers, VRT and modern tractors.
One of the biggest benefits of the technology of PA is the invention of the on-the-go yield monitor (YM). YM’s are great places to start a PA program because YM’s maps the end product of your years work. YM’s, when calibrated properly and combined with a GPS, allow for the accurate mapping of yields in a field, capturing variability, and allowing for the investigation of the variability to determine what and why thing are happening in a field.
Without a yield monitor you are only capturing one dimension of variability in your field, be it soil type, fertility, or drainage just to name a few. With the yield map, you capture the combined effects of all the variables and can them to build your management plan and deal with it’s variability. Dealing with the variability might include using VRT, targeted drainage, and changes within field practices or whole farm management practices.
Two of the most important but overlooked aspects of PA are As Applied Mapping and Data Analysis. As Applied Mapping is the capture of the real rate applied vs. the target rate when using VRT. It does no good to do VRT and assume that you applied your target rate when you can actually see what happened by mapping the as applied rate. Anytime farmers have anything done using VRT, either by themself or by a custom applicator, they should be getting an As Applied Map to confirm the target rate vs. the as applied rate.
When we have all the data collected we can then use analysis to see what patterns or relationship may exist in our field to help up refine our management even more. There are numerous examples of producers collecting great amounts of data and never doing any analysis to see cause and effect, what relationships exist, or if their management decisions resulted in a return on investment.