The majority of the fields Brad Beutke farms look flat and black from the road. But as the old saying goes, looks can be deceiving.
“There’s a lot of variability out here you wouldn’t necessarily expect in central Illinois,” says Beutke, who grows 2,600 acres of corn and soybeans near Clinton with his business partner, Rod Wilson.
Variability in soil types, water-holding capacity and field topography are just a few of the reasons the two farmers rely on information they glean from management zones to help them improve their agronomic practices.
“We started out using management zones to variable-rate lime and dry fertilizer,” Beutke says. “Every year we’re finding new uses for them.”
The zones have helped the partners fine-tune nutrients, fertilizer application timing, hybrid and variety selection and seeding rates.
Being able to variable-rate plant corn by management zone has delivered a 15% reduction in seed corn costs annually, Beutke adds.
“We used to plant 36,000 seeds on everything, but now we’re doing that only on the most productive zones,” he says. “We’re down to as low as 28,000 in some areas. In a dry year in those areas we’re helping ourselves because we’re not trying to feed and water as many plants,” he adds.
Beutke and Wilson use zones as small as an acre and a half and no larger than seven acres. Drilling down to identify variable ground within fields allows them to tailor their management practices to highly focused areas, something predetermined grids don’t allow.
“With this type of management system, we can address the weakest link in each zone,” Isaac Ferrie, field agronomist for Crop-Tech Consulting, told farmers attending the Farm Journal AgTech Expo last winter.
Ferrie says most farmers get “fired up” about management zones, once they find out how much they can help them improve their fields and crops. But the challenge, he adds, is zones require a lot of work on the front end.
“The biggest thing is gathering data—correct data—and using calibrated yield maps and weighing treatments to verify the accuracy of your yield monitor results,” he says.
Soil types, topography, yield and crop history and recollections of crop performance in wet versus dry years are examples of the kinds of information you need by field to build the zones.
You also need some comfort level with technology. You can start by drawing the management zones on paper yield maps with a marker. You’ll then need to use a GIS (Geographic Information System) mapping software program to create the zones for variable-rate prescriptions.
If you’re not handy with technology, get help from a local agronomist to establish the zones. If you can’t locate one, check with local retailers and company sales reps.
With management zones, you don’t wipe the board clean every year, Ferrie cautions. Instead, you can slightly update your zones each year as more agronomic information is gathered.
“This gives us repeatability so we can see how our management practices are working from year to year, especially with different weather conditions,” he says.
Beutke spends a day each winter evaluating his farm’s variable-rate maps and updating management zones. If he identifies an area that needs more nitrogen, for example, then he makes that adjustment the following season.
“The whole point of zone management is to identify the limiting factors in each zone and then change practices to economically maximize yields within each one,” Ferrie adds.
