For peanut farmers seeking another way to increase crop yields, the solution may be as simple as making more accurate row passes during harvest. That kind of precision agriculture is being effectively implemented with a real-time kinematic (RTK) tractor system at the Auburn University Extension System research station in Headland, Ala.

“This and smart bombs are first cousins,” says Dallas Hartzog, Extension agronomist and professor at Auburn University. “This technology uses a base station that receives and transmits a satellite signal to the receiver globe on the tractor. The computer on board the tractor then reads that and tells the tractor where to go. You don't even have to touch the steering wheel.”

Using this technology, Hartzog and colleague Kris Balkcom are researching the effects of deviating from the row when harvesting peanuts. Experiments are being performed harvesting directly on the row, 3.5 inches off the row and 7 inches off the row for both strip-tilled and turned land with single and twin rows.

Balkcom says he chose those numbers for practicality and repeatability. “Most farmers will typically deviate about 3.5 inches off the row. The 7-inch measurement was chosen just to show repeatability in our results. Most farmers won't deviate that far off the row.”

Just by being 3.5 inches off the row, farmers can lose several hundred pounds of peanuts, Balkcom says. “We've found that with a 3.5-inch row deviation, 840 pounds of peanuts were lost. That makes a big difference money wise.”

This difference can actually help pay for the seemingly hefty cost of the RTK system, Balkcom says. “The average cost of the system is around $40,000. Calculating the loss of 840 pounds of peanuts at $.175 per pound with 350 acres, the RTK system pays for itself. Still, even if you aren't deviating 3.5 inches all the time, you probably are half the time, and in two years, the system could be paid for.”

Large growers looking to cut costs with two six-row inverters could save money by purchasing only one RTK system, Balkcom says. “Growers could put the system on just one of their tractors, skip a row and leave a perfect spot for the other six-row inverter to run in. It's like having the precision of two systems by buying only one.”

Balkcom says the effects of deviation are visible when digging before yields are even calculated. “If the peanuts are standing upright, you're on the row. If they're leaning one way or the other, you've deviated and need to move the opposite way to get them back to inverting upright.”

While technology is helping to correct that deviation, Balkcom says research and technology were responsible for it initially. “With today's new peanut varieties, chemicals to take care of disease, and a good rotation, you have healthy, green vines that are harder to see than the withered, diseased plants of years ago. This makes it much harder to find the rows. Also, in order to save time, farmers have switched from two-row tractor diggers that allowed the tractor wheel to run in the same path to get to the next row to big, six-row diggers with which you can't look over and see precisely where you've been running. It's harder to keep those in track because you're out looking for the row at every pass.”

Balkcom says another interesting result of the study has been the comparison of strip-tillage versus turned land. “Last year, we lost more peanuts deviating off the row with strip-till than we did with turned. That's something to consider when calculating the fuel and labor savings of strip-tilled.”

In addition to its benefits for peanut yields, Balkcom says the precision placement helps decrease reliance on favorable weather conditions for digging. “If you needed to be digging and a storm was coming, you could dig at night because light is not required for the system to recognize the row.”

Another advantage of the RTK system is creating a less stressful digging experience, Balkcom says. “Digging peanuts can be pretty frustrating and tense. It's a lot easier to run this system all day when you're not fighting to find the row.”

The system can also cut down on the amount of skilled labor needed to operate equipment, according to Christopher Parker, peanut farmer and student worker at the research site in Headland.

“It's hard to find good people to drive a tractor now. With this system, you can cover more acres in a day with less help and train pretty much anyone to help you. You can make someone look like a really good tractor driver with this system.”

While the RTK system is not restricted to harvesting peanuts, its cost benefits can be extended to herbicide, pesticide and fertilizer applications, Balkcom says. “Things like that will keep you in business and allow you to remain more productive.”