Taking a Fresh Look at Yield Monitors

Since first arriving in cotton fields in the late 1990s, yield monitors have repeatedly evolved to keep up with grower demands. But, as precision agronomists point out, grower appreciation for the technology has evolved right along with it.

“The technology has kept up with, and perhaps exceeded, grower expectations,” says Dr. George Vellidis, a professor in the crop and soil department at the University of Georgia. “We’re gathering data now, and the problem is people have not yet figured out how to use it properly. I know many farmers who are collecting yield data, but they never bother to download and look at it because they don’t have the time or don’t see the value.”


That’s just the type of mindset that Vellidis and his counterparts are trying to eliminate. Through a paper he produced in conjunction with Cotton Incorporated, Vellidis has tried to shine light on the many different ways yield monitors can add real value to a given farm.

“You’re leaving money on the table if you’re collecting that data but not looking at it,” Vellidis says. “There’s valuable information there.”

While many producers are under-utilizing the data available to them, others are creating new ways to be more efficient and save money through yield monitoring. One increasingly common use is for growers to conduct variety tests on the unique conditions of their own operations, using yield monitors as the ultimate gauge.

“They’ll plant different strips with different varieties, and, with a yield monitor, you just harvest and produce a map and see how different varieties perform differently under similar conditions,” Vellidis says. “Technically, you may want to be calibrating for different varieties. For example, a large-seeded variety will have different weight that is not lint weight. So that’s something to keep in mind.”

Another classic way to find real value in yield monitoring is through variable rate fertilizer applications. On a base level, farmers are able to find the floor and ceiling of a given area in a field through their yield monitoring and apply variable rate fertilizer from that data.

“They may even try variable rate seeding to match the yield variability of that field,” Vellidis says. “You could think of, ‘I took off so much yield, this is the amount of nutrient I took off, this is how much I need to replace.’

“The yield monitor is the perfect way to assess what’s really going on in a field.”

Vellidis and his counterparts provide case studies on the numerous ways farmers are getting the most value of their yield monitor data in the booklet they produced. Cotton Yield Maps: Tools for Increasing Efficiency and Profitability can be found on the Cotton Incorporated website’s precision agriculture section.

Ultimately, Vellidis says, the yield monitor is the key ingredient to seeing rewards from any precision ag program. He acknowledges a quote he once heard from a Georgia farmer, Mike Newberry, which has stuck with him for over 20 years.

“He said ‘Yield monitors are the entrance exam and the final exam of precision agriculture,’” Vellidis recalls. “What he meant by that was that, unless you have a yield map, you really don’t know what your variability is, and you don’t really know whether you should be adopting precision agriculture or not.”

If your fields are uniform, Vellidis says, then there’s no reason for you to look into variable rate practices.

“On the other hand, if you measure variability with your yield map, then you know how to address the problem. And, at the end of the season, you use your yield map as your final exam to see if your management practices have made a difference.”


From Cotton Grower Magazine – August/September 2018