Precision-ag trends

Ann Marie Edwards, Iowa Farmer Today Columnist 

Precision agriculture continues to affect how farmers accomplish field tasks and goals.

We continue to see an evolution of technology. Farmers are increasingly using tablets and smart- phones to help with data collection or help them identify and record crop and pest problems, select precise hybrids, identify specific problem areas and increase their ability to cover more ground with ease.

Brian Luck, University of Wisconsin-Madison Extension agricultural engineer, describes precision agriculture as management of scale.

“We’re looking at managing the field, not basically as a one, whole field unit, but down to different soil types — even down to one square foot or meter. It’s about managing that special variation over the field,” Luck says.

Newer machinery has GPS systems that are able to tell the machine where it is in the field.

Photo Courtesy AgRobotics

“There are variable-rate drives on a lot of our agricultural equipment already, so farmers can make fertilizer applications or chemical applications, and we can do seeding to vary rates across fields based on special variability,” Luck says.

“The goal is to place your inputs where they will do you the most good.

“So, ideally, you want to put your fertilizers and your seeds and everything at higher densities on your better soils. We have control capabilities on our inputs to place them exactly where they need to be.”


It’s not just large machinery that is delivering precision tools.

Farmers are starting at the beginning in using precision soil sampling to help them know the most about their soils.

AgRobotics Autoprobe uses precision ag technology to collect soil samples on-the-go. The machine follows a GPS prescribed path, collects samples and stores each soil sample in a container for lab analysis.

Frank Moore, a farmer and an ag business consultant in Northeast Iowa, purchased an AutoProbe this winter.

He uses the AutoProbe to assess the effectiveness of manure management plans in areas with intensive livestock operations. 


“The Iowa Department of Natural Resources (DNR) is paying closer attention to fields where manure is applied here in Iowa,” says Moore.


The change has fostered a greater need for high-efficiency, mechanized soil sampling. Farmers applying manure are required to better document what’s in their soil, particularly phosphorus and potassium. 


Moore says valid soil tests help complete the Iowa Phosphorous Index document.

He says a farmer needs 25 to 35 cores per sample to be statistically significant for phosphorus.

The AutoProbe machine helps with the process. Moore uses the AutoProbe to pull 20 to 40 cores per sample.

And, instead of having one sample represent 10 acres, one sample from the AutoProbe represents 21⁄2 acres. So, it exceeds the requirement by far.


AutoProbe makes a straight line across a zone or grid square, pulling a new core every 17 feet, regardless of artificial boundary lines.

As a result, cores are never clustered in a bunch. 


Cores for a single sample that are taken in close proximity don’t give a true picture of soil conditions at other spots in that zone or grid square.

John Fulton, a biosystems engineer at Auburn University and Alabama Extension, says site-specific input management, particularly for soil fertility, is one practice many farmers have already adopted.

He says he believes there will be an even greater need in the future to collect a large number of soil cores to better characterize soil fertility levels.

Fulton says precision tools focus on reducing inputs by burning less fuel in equipment, reducing fertilizer applications and minimizing runoff.

He says he believes guidance control on planters, and more specifically on sprayers, has enhanced a farmers’ ability to more accurately place inputs and reduce overlap.

“We’ve been able to use technology to become more accurate and minimize over-applications of inputs in areas of the fields,” Fulton says.


Wireless data transfer or telematics has had a huge effect on farmers and their ability to transfer data wirelessly between machines.

“It will be important that we can take that data off the machinery so we know not only know how the machinery is operating, but also have yield information and other data available for analysis,” Fulton says.

Unmanned aerial vehicles or drones are growing in interest and will be important so farmers can more quickly identify the early presence of insects and other problems in fields.

Finally, Fulton says data-management software is important as farmers make decisions on selecting the right hybrids or varieties or using best-management practices for crops.

Luck says he believes we will continue to see more adoption and developments in autonomous machinery and vehicles that will be able perform tasks in a field.

Fulton encourages farmers who want to learn more about precision agriculture technologies to stay on top of the latest information coming online.

He advises farmers to stay engaged through social media and attend precision-ag conferences.