Midwestern farmers are digitally divided over a common precision agriculture tool found in many of their combines. Some producers know what to do with yield monitor data, and some don't.

"The most common question that I get from farmers is, 'What do I do with all this data?" says Jess Lowenberg-DeBoer, a Purdue University agricultural economist and director of Purdue's Site-Specific Management Center. “Unfortunately, the analysis software and interpretation skills have not kept pace with our ability to collect the data."

Yield monitors have been around about a dozen years. Approximately half of the Corn Belt's crop acres will be harvested by yield monitor-equipped machinery in 2004, Lowenberg-DeBoer says. Around a third of the combines with yield monitors also are fitted with Global Positioning System (GPS) receivers, which allow farmers to record the location of yields and make yield maps.

"There are three basic areas where farmers can use yield monitor data," Lowenberg-DeBoer says. "One of them is diagnosing problems and identifying areas of a field where the soil is pretty good but it should be yielding better. Another possible use of the data is identifying management zones for next year. For instance, which areas had similar yields? Which ones can you treat as being alike for fertilizer spreading, and for choosing hybrids and varieties for other management practices?

"The third use is to test technology. This takes a little forethought. It means you have to lay out your field comparisons in the springtime when you plant. You might do split planter trials. Some farmers do strip trials. Some others compare large blocks. All of those can be valid comparisons, if done correctly."

Field diagnosis is often the easiest task among the three to perform, and does not necessarily require specialized software, Lowenberg-DeBoer says. A farmer needs only a yield map, which does require the combine be equipped with a GPS receiver.

"Usually when farmers look at their yield maps they know why yields were low in specific areas – an eroded knob, a drowned-out spot or a sandy patch," Lowenberg-DeBoer says. "But then there are those areas where the problem is not obvious. Soils may be good but yields are below potential.

Yield maps help farmers identify those below-potential areas for close examination. Was the stand adequate? Was it an insect or weed problem? Should we test for nematodes? With some luck the grower can identify a problem and a strategy to deal with it next year."

It shouldn't take a farmer long to peruse a yield map and find trouble spots. A more detailed analysis takes time – a precious commodity for most producers, says Lowenberg-DeBoer.

"One of the biggest issues in all of precision farming is the management time required in order to make use of this technology," he says. "Right now, it still tends to be quite time consuming. It takes sometimes weeks to figure out what a yield map means. In terms of getting a rough analysis, a look at a yield map often tells a lot. That is something that can be done within an hour or two. The finer analysis may take some time."

Because of the proliferation of technology, a high-value use of yield monitor data is technology testing, Lowenberg-DeBoer says.

"Biotechnology, new tillage options, pest management alternatives -– all these things are coming down the pike and not all of them are appropriate for everyone," he says. "So it's very important that producers test the most important ones on their own operations. "In the wintertime when you have a little bit of time to think about planning for the coming season, decide what technology you want to try and have questions about. You can't test everything – there are just too many options out there."

Yield monitors also are valuable for mapping grain moisture content, Lowenberg-DeBoer says. A few percentage points either drier or wetter can equate to better profits or higher expenses.

"You may find that within your field you have very large differences in grain moisture at harvesttime," he says. "This may be due to genetics. You may have two hybrids and both yield approximately the same but one has much higher moisture, and that means down the road a much higher cost because it has to be dried."

Yield monitors of the future also will gauge grain quality, Lowenberg-DeBoer points out. Such technology already is in use in Australia."There will be quality monitors that will provide information on protein, oil content and starch in the grain. That information helps both in marketing decisions and in future management."