When contemplating how to steer a farm toward precision technology, growers face a dilemma. Should they be collecting yield data or addressing soil fertility issues first? MFA's Agricultural Systems Information Lab manager, David Hughes, says do both--on a schedule.

Since the inception of precision agriculture, initial adoption of the technology has been scattershot. Some growers opt to outfit their equipment with GPS and yield monitoring first, figuring they can get the hang of the equipment and some interesting data as they ease into management practices based on precision technology. Others focus on analyzing their soil via intensive sampling so they have a more focused picture of the direction intensive management can take them.

David Hughes, manager of MFA's Agricultural Systems Information Lab (ASIL), recommends combining both approaches in a planned, multi-year adoption of new, intensive management practices.

"There are separate realities that affect how quickly you can adopt precision technology on your land," said Hughes. "On the service provider's side, there is time required for the logistics of data collection and analysis in order to turn around plant food recommendations. On the production side, there is a cost factor for a grower who is paying for intensive soil sampling and possibly a fertility buildup."

Hughes said that after years of facing these realities, the ASIL philosophy is to spread both logistics and cost by enrolling a portion of a farm's acres into a precision ag program each year over a 4-year time frame. For example, bringing a 1,200 acre farm into a precision ag program would mean 300 acres get enrolled the first year.

Hughes said the first-year objectives for those 300 acres would be to address soil pH and nutrient availability. That's done through intensive soil sampling.

"The goal is to evaluate nutrient availability in order to make recommendations for a buildup, where needed. Initially, we want to stick with a build plus maintenance philosophy under the assumption you can take that field to its optimum fertility levels for its production potential," said Hughes, explaining that the rest of the farm shouldn't forgo its usual yield-goal fertility applications.

And he suggests that in order to maximize return for precision technology, producers should have an aggressive, 4-year buildup and maintenance fertility program. To fit the rotation of bringing a quarter of the farm in over 4 years, Hughes said the fertility buildup should fit the time frame. An example approach: Fertilizer recommendations are based on crop removal for the first year. In the second year, the recommendation is for crop removal plus half of the needed buildup, as well as lime to address pH needs. The third year is based on crop removal. And the fourth year is crop removal plus the second half of buildup (and if no-till, the second lime application). This approach might not work in every situation. For example, where a significant buildup of phosphorus is required, the build portion of the recommendation may be divided by 3 or 4 years of application in an environmentally sensitive area or where significant precipitation is expected following application.

All told, based on the initial intensive soil testing, the field should be at or near optimal fertility levels at the end of the fourth year. That means, for these 300 acres, pH and nutrient availability begin to be ruled out as factors that limit yield.

"The other aspect of those first 4 years," said Hughes, "is collecting yield data and looking annually at the other factors that can affect yield--weed pressure, drainage, variety selection. We can use that data on a short-term basis to work at fixing those problems."

Total startup cost? For the first 300 acres in this example, it's roughly $2,550 for intensive soil samples and analysis and about $5,500 for yield monitor and GPS. The soil sampling costs will be similar for each of the remaining three-quarters of the farm. The cost for yield monitor and GPS, of course, will be spread over the entirety of enrolled acres.

Once each section of the farm has hit the 4-year mark, it is ready to move into the more advanced stages of MFA's Precision Advantage program.

"At this point, we can use the 4 years of data to look at consistent trends with yield," said Hughes. "Once those are identified, we can do a few things. We can develop sub-field management zones based on productivity potential. We can move toward a "sufficiency" approach with plant food--even using yield data to fine-tune the fertility recommendation on individual fields. We can begin to make management decisions about variables that we can control such as drainage and variety. And we can begin to deal with variables we can't control like topsoil depth and so forth."

Hughes said that in years 5 through 8, precision agriculture hits its pace as a tool for the hyper-management that pays big for farmers.

"Because you've got good information for a number of years, and because you've ruled out lack of nutrient availability and narrowed down other variables, at this point, you'll have the potential to investigate the feasibility of variable-rate nitrogen and variable-rate seeding."

Hughes said that, by approaching enrollment in chunks, growers are able to spread costs, amend soil fertility and gather important yield information all at the same time.

"You've got to build yield history, but why wait until you've done that to start with soil fertility adjustments? What makes this system nice is that you can focus on improvement without confusing the issue of where to start. And after each segment matures into that fourth or fifth year, you're where you need to be for the more intensive precision payoff."