Soil, Water, & Topography (SWAT) MAPS
SWAT MAPS are built by integrating multiple layers of field data into a single map which is the basis for soil applied fertilizer, seed, herbicide, and fungicide applications. Using a zone management system based on stable soil properties such as electrical conductivity, topography, elevation, organic matter, and water flow provides farmers with a comprehensive depiction of the factors influencing the crop and helps to make decisions involving crop inputs.
3 Key Factors for Building Soil-Based Zone Maps
- Salinity, sandy to heavy clay soils, peat soils, and solonetzic soils impact yield and fertilizer response
- Topsoil depth and organic matter levels
- Most profound factor on yield and fertilizer response
- Dry (knolls) vs. wet (depressions)
- Mobile nutrients moving in water
- Landscape position (knoll, midslope, depression) influences moisture, erosion history, organic levels,
pH, and soil fertility levels
How Are SWAT MAPS Made?
SWAT MAPS are built using layers of data that characterize the soil, water, and topography features of the field. The layers are integrated into the SWAT MAP depending on how much influence they have on the productivity of the field. Any one layer is useless on it's own - it is the combination of information from all five layers that make SWAT MAPS valuable.
Click on the maps below to learn what each map describes and how it influences the field.
SWAT MAPS are management zone maps derived using multiple layers including soil, water and topography.
This makes a SWAT MAP unique because:
1. It has the ability to delineate management zones that combine water driven yield potential and nutrient
responsiveness for VR fertility. Both yield potential and responsiveness of the soil are the most important factors in determining applied fertilizer rates, and therefore ROI. Soil responsiveness and yield potential are independent of each other; in other words, a high yielding area is not always highly responsive to nutrients, nor is a low yielding area always poorly responsive.
2. It models water flow and accumulation. Water is the foundation of understanding crop variability. It is a major factor in soil acidification, organic matter, mineralization, and nutrient loss. It is the cause of salinity, nutrient movement downslope, and is the driver of yield potential. Water is the root cause of most soil variability.
3. It is based on stable soil and topography factors and therefore doesn’t change every year. For a variable rate fertilizer program to be effective, it should be able to delineate the areas mentioned in the chart below. Not every situation will necessarily exist in every field, every year, but it’s important to be able to identify them if they do. Yield potential is determined by water, primarily affected by landscape position, water flow, and soil texture. Fertilizer response probability is determined by soil testing and is specific to each individual nutrient. SWAT MAPS simply give us the ability to apply existing, proven soil science principles spatially within a field, at a higher resolution of management compared to traditional composite samples on one field.
Farmer, Dueck Farms
"We farm a variety of soil types and topography usually in the same field and SWAT MAPS have really helped us improve plant stands and even out crop maturity across those fields. Crop grades, grain moisture and straw management have all improved with VR seeding and fertility."
Owner, Fieldwalker Agronomy
"Precision ag isn’t just a once and done. It’s a constantly evolving process. That’s part of what attracted me to SWAT MAPS. It’s a systematic process to building seed or fertilizer response zones. It’s repeatable; you go and do it once and then you’ve got management zones to work with. The map is just the starting point. We use it to identify opportunities where we will get a response."
Co-Owner, Next Level Ag
"All good decisions come from data, without a good base layer map being the foundation for good decisions on any operation there are to many decisions made from testimonials not data driven off of the farm. SWAT is the answer to getting an operation more in tune with making proper input decisions. We need this layer of decision making for yesterday, today and tomorrow!"
Farmer, Rosengren Farms
"Our whole farm has been mapped with SWAT MAPS. Our soil and available water changes in short distances on our land and the SWAT MAPS mapping system delivers high definition maps representing the fields."