Gary Wagner understands all that - and he knows that if a dramatically new way of doing things is to catch hold and grow, it must be both affordable and nonintimidating. By way of comparison, the much lower cost and increased user-friendliness of personal computers in the mid-1990s versus earlier generations. The result has been a wide-spread acceptance in concert with an ever expanding range of applications. Wagner believes a similar scenario is beginning to unfold in the case of precision farming technologies and applications.
How are the Wagners presently utilizing precision farming equipment and methods? There are several ways:
- Yield Monitoring
As indicated earlier, the Wagners’ John Deere combines are equipped with monitors to provide continuous - and accumulated - yield and moisture readings for their sunflower and grain crops. There are several brands of yield monitors on the market, with the Wagners currently using an Ag Leader 2000. A load cell measures the force of the grain coming off the clean grain auger, converts that into yield per acre, and enters and stores the data on a continuous basis. While initial sensor plates were not designed for lower-density crops like sunflower, Wagner says his units can now measure his confection sunflower yields with about a two-percent accuracy.
Moisture content of the harvested seeds is also calculated, with the sunflower moisture levels instantly corrected down or up to a predetermined percentage. That feature allows a consistent comparison of yields - regardless of actual moisture content - across a single field, between fields and even between growing seasons.
As he travels throughout a field, Gary Wagner can also retrieve an up-to-the moment average of the field’s yield and moisture, as well as an average for the load presently in the hopper (up to a total of 999 separate loads). Other computed data include the harvest date, time of day, combine ground speed and number of acres harvested. All of the information is stored on a disk, which the Wagners later download into their office computer and print out when needed.
Since 1994, the Wagners have been working with North Dakota State University agricultural engineers in the development and field testing of a prototype on-the-go sugarbeet yield monitor. Among the advantages is the ability to ensure that the trucks delivering beets to piling stations are not overloaded as they leave the field. Minnesota law now allows enforcement officials to review piler scale tickets for up to 30 days after delivery and levy fines if a ticket indicates a truck was overweight.
- Field Maps
Hand in hand with the collection of the crop yield data is the generation of field maps. Like others, the Wagners use these maps for much more than just satisfying their curiosity about how their crops yielded in a particular spot. While harvesting, they also have the capability to document the coordinates of problem weed patches, poorly drained field sites and other problem areas for future corrective action, and then map these items.
Gary Wagner says field drainage is one area where the mapping of sunflower fields is particularly useful compared to grain or sugarbeet field maps. “Sunflower is sensitive to excess moisture. It doesn’t like water-logged soils,” he notes. “So it will help us map where we need to improve our drainage; and if we correct some drainage problems, we’ll raise the productivity of all our crops.”
For the past two years, a prototype unit in their combine has allowed the Wagners to geo-reference weed patches or other problem spots. “There’s a four-button control on it, and you determine what those four items are going to be (e.g. , wild oats, Canada thistle, quackgrass, drowned-out spots) before you go into that field,” Gary explains. In 1995, for example, he mapped out quackgrass areas in sunflower fields. Because of a late, wet harvest, the Wagners were unable to treat those areas prior to the onset of winter. “But marking them, I was able to determine how many acres I need to spray with Roundup this spring.”
Those spots will have been treated with a mini-sprayer carrying a GPS-based mapping notebook, allowing the sprayer to automatically switch on and off, based on the weed patch coordinates. The Wagners also mapped wild oat patches in their grains and sunflower. In both cases, the system allows them to treat only where needed, thereby cutting back considerably on the amount of herbicide required, compared to a conventional broadcast treatment.
- Grid Soil Sampling/Variable Rate Spreading
Of all the crops in the Wagner rotation, sugarbeets are by far the most suited to grid sampling and variable-rate spreading of fertilizer - especially nitrate-nitrogen. That’s because the beet payment system American Crystal Sugar Company, provides substantial financial incentives for the fine-tuning of nitrogen management that results in higher sugar content and lower impurity levels.
Soil sampling in three- to five-acre grids - coupled with variable-rate spreading of fertilizer across those grids in order to “even out” a field’s fertility levels - generally has been a profitable undertaking for Red River Valley sugarbeet producers. This practice was employed on about 35 percent of American Crystal’s 1996 beet acres - up 10 fold from the prior year.
Grid sampling/variable-rate spreading typically is most profitable on fields containing significant nitrogen variability from area to area within the field. It may not pay off where nitrogen levels are fairly consistent throughout the field. Because of the cost of grid sampling (usually more than $20 per acre if custom applicator fees are included), many sugarbeet growers are utilizing the practice only preceding their beet or potato crops, not prior to plating other row crops or small grains.
For nitrogen specifically, a related procedure call “topographical mapping” appears to work quite well while simultaneously costing considerably less than grid sampling. This approach uses GPS and laser equipment to log field elevations to within 0.01 foot. Red River Valley research to date has shown a high correlation between a field’s topography and its nitrate-N levels.
During the fall of 1995, the Wagners constructed several laser-generated topographical maps of two 80-acre fields and began soil testing based on micro-topography. Instead of testing 18 to 20 sites within an 80-acre fields (as would be the case using current grid sampling standards), they tested a half dozen. “It appears topography works well in the Red River Valley if you’re testing for soil nitrates. It has an extremely high correlation,” Gary observes. “For P and K levels, though, we don't see that correlation.
“So our attitude is, we’re probably going to grid soil sample our fields once every five years for P and K levels (to six inches; two-acre grid size). Then, for nitrates, we’ll probably go with topography every year.” While the cost of grid soil sampling has been prohibitive for grain and sunflower fields, Wagner believes topographical mapping would be economically viable for many producers.
Remote sensing is an era which Wagner believes will have a dramatic impact in the Red River Valley. “Research has shown there's a fair amount of nitrogen that gets returned from the sugarbeet plant to the soil and is used by the next year’s crop,” he points out. “By using satellite imaging or low-aerial photography - or perhaps by having a camera on the tractor that will be able to ‘sense” the amount of nitrogen in the leaves just before topping the beets - we can build a nitrate map based on the leaf content.” Since there's a high correlation between leaf color and sugar content, such a map could essentially become a “sugar map” of that field while also providing a good indication of how much nitrogen was being returned to the soil for the ensuing crop.
The Polk County farmer foresees remote sensing for crops like sunflower and wheat as well. “Once they determine the ‘signatures’ for diseases, weed problems, etc., that information is going to be extremely valuable,” he states.
- Variable-Rate Seeding/Varietal Substitution
Though the Wagners have not yet experimented with on-the-go changes in seeding rates, Gary believes this is another facet of site-specific farming along with real promise. On rolling ground in particular, being able to increase or decrease rates depending upon soil and moisture conditions at the time of planting (e.g., reducing populations on tops of knolls) could help optimize productivity from spot to spot within the field.
For sugarbeets, Wagner envisions seen more benefits form a multiple-variety planter which would allow the operator to shift between seed varieties with just a flip of a switch in the tractor cab. “For example, right now if we grid sample and have an area with high nitrogen, we simply don’t apply fertilizer in that spot,” he illustrates. “But if we could switch from a high-tonage variety to a high-sugar variety, we could plant areas with high nitrogen into the high-sugar variety and get a better return.”
Has the Wagner brothers’ considerable investment of time and dollars into precision farming technology and applications started to return dividends?
Gary says it’s still difficult to accurately quantify the inputs saved or productivity enhanced as a result of their precision-farming focus. “The way we look at it is, we’re going through a ‘master’s degree’ program [i.e.], we’re having to do four to six years of learning before we can really start benefiting a great deal from what we’re doing,” he remarks. “But in terms of how we approach farming a specific piece of land, I have a totally different outlook.” At the core of that revised outlook is a conviction of the need to collect a wealth of information and then integrate that information into a comprehensive system that emphasizes the proper placement of inputs in a manner that will optimize productivity and profit. It’s also an environmentally sound approach, he adds, since it is based on applying inputs only when and where needed and then only in the required volume.
Though there has been a literal explosion of precision farming technology within the past two or three years - along with a concurrent wave of promotion and publicity - Gary Wagner says this revolutionary phase of agriculture is only the beginning to hit its stride. “Right now, the technology is still too new for us to realize a lot of direct benefits from it. But within the next three or four years, the computer software coming from universities and other sources to help with analyzing and decision making will be in place,” he predicts.
“By then, we’ll have the advantage of four to six years of information ready to run through the analysis process. We’ll have history that we can dump right into the system and begin using. All of the information we’re collecting now can be geo-referenced and repeated. We’ve been putting the pieces together so that when the technology becomes truly available, we’ll take advantage of it.”