"You can take the receiver off the tractor and plug it into the combine and, boom, you're off and running," said Nelson.

Just over the horizon, even more technology is coming to the farm.

Researchers at the University of Illinois are working on a small robot that can identify individual weeds in a field and spray them with herbicide so farmers don't have to spray an entire field as they commonly do now. The robot will move perhaps 2 mph picking out weeds by color, location and other characteristics, engineer Lei Tina said.

"Actually we have a prototype," he said. "We can identify the individual plant pretty well."

The technology is years from commercial viability, however.

Then again, Davidson said, what's expensive and far-fetched today may quickly become cost-effective if fuel and fertilizer costs don't drop back.

"All of these things are so tied to energy," he said. "I don't expect them to come back down."