Robertson says the “ugly” aspects of precision farming in the Midwest, is that “dealer support is almost non-existent in some places. They can sell it, but they can’t support it. As-applied mapping is still non-existent for the areas I work in. Fertilizer and chemical dealers are reluctant to provide as-applied maps after they do variable-rate applications.”

Robertson says Midwest precision farming tends to “oversell” the accuracy of RTK. But even so, “we don’t need RTK on everything. There is still a lot of inoperability within the hardware. We’re still trying to plug brand X into brand Y to get zero results.”

Making precision agriculture work on your farm requires a scientific approach, according to Robertson. “Precision farming is collecting data, analyzing that data, deriving a conclusion, assigning a value to those conclusions and then and only then, implementing an action plan based on the value of the conclusions.

“That seems fairly simple. But in reality, we skip a whole bunch of steps. For many people precision farming is collecting data and then implementing an action because we have the tools to do it.”

The key to harnessing the power of precision agriculture, according to Robertson “is to model the entire environment. We can’t do that if we are focused on just fertility, or soil type. Don’t be so focused on one thing in that field that you don’t look at something that’s telling you a story that’s going to solve that problem.”

For example, a field drainage map may explain why yields differ in two areas of a field even though they have the same soil type. “We could be over-managing one area and under-managing another. We have to consider all variables when we consider yield. But yield is not a variable. Yield is an autopsy. Yield is the post-mortem, the result.”

Robertson says to not underestimate the knowledge and experience of the farmer. “After we got started in precision farming, I handed my father a yield map, and he looked at it and said already knew that’s what it would look like. During his life, he had made 77 harvests off those fields. Based on the year, he could tell you where the high and the low yields were going to be. But that’s experience. So much of what we do in precision agriculture cuts the farmer and his experience out of the action being taken.”

Robertson says to partner with an information technology provider “who will welcome you the farmer in the analysis of the variables, and who understands that yield is the result of variables and not a sales tool. The biggest mistake we can make is replacing the farmer with technology.”

Farmers should be willing to consider all of the factors affecting yield, whether it be fertility, pH, insect pressure, drainage or CEC. “But remember that spatial variability is determined by our sampling density. In other words, how the pictures are going to look is determined by how you sample.”

Precision farming is not necessarily about increasing yield, Robertson said. “It’s about profit. I want to work with profitable farmers. I don’t care if they win yield contests. Our true focus should be on the 20 percent of that data that is going to make us an 80 percent return.”

erobinson@farmpress.com