Beginning in 2006, after using precision ag technologies on his farm for more than a decade, Mike Ellis hit precision pay dirt. That's when he began testing planter and sprayer systems that allow him to shut off small planter and sprayer sections to minimize overlap.

After two years, he is seeing consistent savings in the 9% range on seed and at least 12% on herbicides. And he has paid off the technology investment in full.

“This is huge as far as a technology that will profit farmers,” says Ellis, who farms several thousand acres with brothers Bob and Jim in the Shelbyville, KY, area. “I know we have paid for the equipment investment in two years [including a $20,000 investment in sprayer upgrades].”

“This the first time with precision agriculture technologies where it is easy to look at your records and see the technology has paid for itself,” adds Scott Shearer, a precision ag researcher at the University of Kentucky. Shearer has documented the impact on the Ellis operation as it has adopted the new technologies.

Sprayer, planter modifications

The Ellis self-propelled sprayer, which has 48 nozzles spaced every 20 in. on an 80-ft. boom, was set up using a 30-section controller. The spray controller, from Topcon Precision Agriculture, has the most sections currently available. The outer six nozzles on each wing were controlled individually. The remaining 36 center nozzles were controlled in pairs using the remaining 18 controller channels. Nozzle shutoff was controlled using solenoids from Capstan Ag Systems.

Two planters — a 12-row planter with splitters, and a 24-row rig — were set up in various configurations. The 12-row rig was set up in one-, two- and three-row sections using a 10-channel controller, depending on whether it was configured for 12 rows for corn or 23 in the splitter mode for soybeans. The 24-row planter was set in single-row sections using the 30-channel controller.

By comparing likely “applied” areas using the nozzle control technology versus sprayer runs without the technology, Shearer documented herbicide savings in several fields ranging from 16 to 27%. He also compared year-to-year glyphosate expenditures across the entire farm. Glyphosate volume fell 12% from 2005 to 2006, even though Ellis used the 30-section sprayer on only about half the treated acres. Ellis also saved about $200 per field in Roundup Ready fields with grass waterways because waterways didn't have to be reseeded.

Field shapes affect potential savings, both for planters and sprayers, Shearer notes. It is possible to overplant a triangular field by about 4.2% with a 16-row planter without by-the-row controls. A field with a curved boundary can easily result in an 8% overplant.

Continued refinement

Shearer is convinced that planting and spraying by the row and nozzle — or in two- or three-row/nozzle sections — is likely to be profitable for many growers.

As controllers with the computing power needed for individual rows and nozzles become available, other precision benefits will emerge. For example, herbicide application could become more accurate in turns as sophisticated controllers are programmed to vary rates along the boom, Shearer says. Planters could benefit from similar technology, although individual row drives would be needed to accomplish this. “I am convinced that we will need individual electric row-unit drives,” Shearer says. “I truly believe that is where we are headed.”