Features to check out when your farmer friend invites you to help shop for a new $100,000 tractor: Enclosed, climate-controlled cab with AM-FM stereo and business-band radio or cellular phone.
Power-adjusted, deep-cushioned seat with armrests for days in the field that start before sunrise and end well past sunset.
Digital instrumentation panels to monitor engine performance and farming progress.
Radar for tractors?
Whatever happened to the no-frills workhorse with a metal bicycle-style seat _ and, on the deluxe model, an umbrella to shade the driver?
"It's like sitting in the office," Mike Dolan says of the 15-hour days he spends in the cab of an $87,000 John Deere 8560 four-wheel-drive tractor, preparing fields for planting in the gentle hills outside the southwest Iowa community of Greenfield.
His father, Don, recalls starting to farm with a 1956 open-cab tractor that cost $2,600, much less than the $4,080 it would take just to replace the eight huge tires on his son's new tractor.
What was spring field work like in the equipment of 35 years ago?
"Terrible. You were out in the dirt, in the cold all day long," Don Dolan says.
But then came the "smart tractor," costing anywhere from $51,000 to $105,000. Its gadgets are designed to take the drudgery out of field work while making farmers more efficient and better managers of seed and chemicals.
It's more than "a bell and whistle or frill," said Mark Hanna, an extension service agricultural engineer at Iowa State University.
Take the radar option, which costs about $500. Radar on tractors is mounted under the body and is used to accurately calculate ground speed.
Anyone who has driven a car on ice and seen the speedometer rise rapidly as the car fails to move knows gauges can be fooled by rapid wheel movement on slick surfaces. In a tractor, those distortions are caused by tractor tires slipping on soil, or slippage.
Some slippage is necessary to get the most efficient pull from a tractor with least stress on the drivetrain, manufacturers say.
Technology also helps farmers monitor how much chemicals get spilled into the ground. With groundwater contamination becoming more of a public health worry, farmers now have environmental as well as bottom-line considerations, Hanna says.
Larree Imboden, who farms 1,700 acres with his son near the central Iowa community of Dexter, has the radar option on the John Deere model 4455 tractor that he bought in February.
By punching in the width of the tool he is pulling on the console and using the radar and other instrumentation, Imboden gets a readout on the area he has covered and his work rate. He can calculate how long it will take to complete the field, and he also can accurately measure off the land he leaves idle under government farm programs.
More changes lie ahead.
Researchers at Iowa State are studying farm applications for the positioning satellites used during the Persian Gulf war.
By mapping fields by their yield potential and soil characteristics, satellite systems used with smart tractors could enable farmers to vary applications of seed, chemicals and fertilizer.
"When your livelihood depends on this, when it means extra money out of your pockets, all of a sudden you get interested very quickly," says Iowa State's Hanna. "Like the microwave or indoor plumbing, once you get it and get used to it, it's a useful tool."