The foundation of zone management is identifying the variability in the field. A simple starting point is recognizing the differences in soils. The photo indicates the high and low ground and the lighter and heavier soils.
Use today’s technologies to maximize yields, inputs
Farmers have long known that all fields aren’t created equal and that every acre in each field is not the same. Today’s technology now allows producers to easily do something about it. Zone management links precision ag and agronomic practices into one seamless outcome with three key benefits: maximizing yields, improving stewardship and boosting bottom lines.
"For 20 years, we’ve been working to get technology in farmers’ hands, and now it’s time to use the data collected through this technology," explains John Fulton, associate professor and Extension specialist at Auburn University.
Using information on the natural variability in a field rather than using a superimposed grid allows you to pave your own path. Regardless of where you are on the technology adoption curve, there are zone management techniques that can be used.
"Zone management enables you to pick the areas where can you influence a problem by applying the right agronomic practice," explains Farm Journal Field Agronomist Ken Ferrie, who has worked with dozens of farmers to use zone management.
Use current information. The first step is to review what you know to identify the management zones within fields. Soil characteristics, water and fertility management, hybrid selection, pest and disease profiles, and yield history all play key roles. Thankfully, most farmers have collected a gold mine of information.
"Since 1991, we have looked at yield maps as a way for fields to tell us where to identify management zones. Now, we not only have yield maps but data available throughout the season," Ferrie says.
Hybrids have one of the largest impacts on yield, not only from field-to-field but within fields. For example, drainage issues in low-lying zones of the field could be managed by selecting a hybrid that does well in wet conditions. Other examples could include recognizing high pH and planting with a hybrid that is tolerant to those soil conditions, or identifying a corn nematode hot spot and managing it with a seed treatment.
"The data we glean from management zones helps us make an informed decision on treating a whole field when a farmer’s equipment is not yet ready for variable-rate technology [VRT] or the technology to vary that input isn’t on the market yet," Ferrie adds.
Gather more data. After examining hybrids, analyze soil characteristics for existing zones. Look at texture, slope, depth, organic matter, fertility, pH, drainage and hardpans.
"Any zone that you develop must respect soil type, but a lot of management zones are within the soil type," Ferrie says. "We start with soil type or soil texture, and from there the zone may be divided out due to depth of topsoil, drainage or pH issues."
Soil information can be gathered from ground-truthed government maps, soil sampling, RTK elevation maps and soil conductivity maps.
Review and verify results. "Once we identify the zones, we have to investigate what’s causing those differences. One thing you’ll look at is the overall soil fertility. Look for clues for what is happening," Ferrie advises.
- November 2013