If no-tillers want the full benefits of Global Positioning Satellites (GPS) with adjustable rates, they better take the time to make sure equipment is calibrated properly.

“I advise anyone interested in doing GPS and even if just using a rate controller manually that they calibrate it correctly,” Clarksville, Tenn., no-tiller Jimmy Bell says. “Spend a lot of time calibrating it so that you have confidence that what it says it’s putting out is what it’s really putting out.”

Bell has used GPS for several years on his 1,500-acre farm and says GPS programming and electronics have improved considerably during that time.

“It has been a tremendous tool for identifying trouble spots in fields and is good for variety evaluation—which are yielding better, agronomic traits and what varieties work best on what soil types,” Bell says.

“But I can’t give you a truthful answer on how much precision farming pays. There is too much variation from year to year and field to field.”

Yield monitors, Bell says, raise a lot of questions where you can easily visualize where things are good or bad.

“Then you have to ask questions of what are the differences and what can I do to eliminate that problem next year,” Bell adds.

Here are a few examples of problems Bell has identified and moved to correct due to GPS, yield monitors and mapping:

1. Bell field-tested two varieties of Pioneer seed corn—one that was supposed to be ideal for the good, even soil conditions in that…