Farmers just along for ride in tractors guided by GPS

MOULTRIE, Ga. -- Darrell Williams spent part of his childhood behind a mule, plowing the fields on his family's tobacco farm.

"It was hot," he said. "I had to follow that plow and that mule. There was no air conditioning on that plow and no shade."

So Williams welcomed the arrival of tractors. They improved farmers' efficiency and relieved them of some backbreaking chores. Most drivers now sit in shaded, air-conditioned cabs.

Now, with the arrival of global positioning system technology, the 59-year-old Williams is witnessing another major agricultural advancement -- tractors that can steer themselves far more precisely than even the most experienced human operators.

Tractors with GPS autopilots are steered over peanut and cotton fields by the same signals that guide missiles to their targets.

"It's almost unbelievable," Williams said. "It's something to be living in this age, coming from mules to tractors that you don't steer."

Tractors outfitted with the GPS systems have been showcased at farm shows for a couple of years, but this is the first year that workers used one to plant the peanuts that will be harvested during the 26th annual Sunbelt Agricultural Exposition. The expo runs from Oct. 14-16 near Moultrie.

"We'll hook the same tractor to a sprayer ... to a digger and during the show ... to a peanut harvester," said Chip Blalock, the show's director.

Williams, who manages Sunbelt's 600 acres of demonstration crops, emphasized that autopilot doesn't mean driverless. Operators are still required to make critical decisions, set the proper coordinates and make sure the machinery is working as it should.

They also must turn the tractors around at the end of each row. After that, the GPS system takes over, bringing the tractor back on course to make another satellite-accurate pass across the field.

Glen Rains, a University of Georgia agricultural engineer, said a driver with average skills might veer an ordinary tractor off course by 6 to 12 inches while traveling across a field, but GPS-equipped tractors are accurate to within an inch.

Inaccuracy in planting and harvesting can lead to reduced yields and lower profits.

Tyron Spearman, who publishes a peanut industry newsletter, said prices of the tractors are already dropping, but there will be a learning curve as farmers figure out how to use the new systems.

"Plug in the wrong number and you'll go out across the woods," he said.

On the Net

Sunbelt Agricultural Exposition: www.sunbeltexpo.com