NEXT TIME YOU go for a drive in the country, try some road scouting. No, not for weeds (you're supposed to get out and walk your fields for that). We're talking about antennae scouting, specifically for those GPS antennae that seem to be sprouting up out of tractor cabs like mushrooms after a warm spring rain. Those antennae arrays are a sign of change and confirmation that farmers are adopting precision agriculture.

Flash back 10 years ago. Experts predicted that site-specific farming technologies would change agriculture. Farmers responded with a half-interested yawn. The equipment was expensive, and no one knew for sure if the investment would ever pay for itself. But now, as one enabling technology leads to another, the pieces are all snapping together like the picture in a giant jigsaw puzzle. Turns out the experts were right, just a bit ahead of the curve.

While more than a dozen companies compete to be a significant part of this now booming industry, university researchers such as North Dakota State's Vern Hofman are stepping back to take a look at where the technology stands today. Starting with yield monitors in combines, Hofman has been monitoring precision agriculture technologies for six years.

TECHNOLOGY CONVERGENCE

“Variable-rate application has become feasible due to several new technologies, including fast computers and powerful graphical and information management software,” Hofman says. “These technologies are now small enough to be easily carried in a tractor cab.”

The ability to precisely manage field operations can reduce inputs by eliminating overlap on each pass. Tie map-based variable-rate software into the system, and you only apply the fertilizer you need, exactly where the crop needs it. Reduced chemical and fertilizer inputs not only save money, but also reduce runoff into groundwater and waterways.

ENVIRONMENTAL BENEFITS

Precision farming allows conservation tillage practices to be adopted more easily and successfully. A farmer can strip-till or ridge-till more easily with a guidance system, then place fertilizer within a narrow band in the crop root zone. Conservation tillage saves fuel and builds soil health for future crops by increasing organic matter left in the field, which reduces crop water requirements and reduces soil erosion losses.

MAKING IT PAY

The benefits of almost any guidance system become readily apparent after a few rounds of a field. And although you don't necessarily need to have a huge farm to realize those benefits, the primary benefits of guidance systems are in maximizing a large farm's inherent economies of scale. With guidance, you can drive faster, pull wider implements and waste less fertilizer and fewer chemicals on overlaps. Tied in with mapping software, a GPS guidance system allows you to keep better records of fields for comparing yield, weed pressure and inputs in specific sections of each field over a period of years.

MONITORING PROFIT

Another level of precision farming payback can come from adding variable-rate technology to the tractor guidance system. The University of Kentucky has done considerable research in this area. According to ag engineer Tim Stombaugh, the general consensus on the profitability of variable-rate application is that it won't necessarily reduce input costs, but by putting the correct amount of product precisely where it is needed, it should improve crop yields. Determining profit gained through variable-rate application can be a significant data management challenge, with a need to meticulously rule out other variables in a field that can influence yield. Research to date strongly points to benefits from variable-rate phosphorus and lime. Improved income from variable-rate nitrogen or seed may be more difficult to quantify, however.

THE NEXT LEAP

Stombaugh says future technologies may add more certainty. “New tools are being developed each year,” he says. “In the future, new sampling techniques will give better information about variation in field fertility. Sensing technology, such as electrical conductivity and near-infrared imagery, could revolutionize field management strategies. Farmers who have several years of historical data will be able to better use these new tools when they become available. That is why it is important to begin data collection now.”