Case Study: Joe Sullivan

After just a few years of using precision farming techniques, Joe Sullivan can't imagine life without them. Although weather has interfered with his yields, his costs have declined thanks to varying his use of inputs.

By Julie (Douglas) Deering, Farm Journal Media

Technological advancements in today’s machinery and data applications take managing zones to a new level of sophistication where the return on investment is undeniable, especially as margins begin to tighten.

Zone management is a great investment to improve input efficiency, says Brian Arnall, Oklahoma State University precision nutrient management expert. "Zones should continually change based on the input being applied," he says. "Once farmers start managing zones and see the benefits, they never go back."

As fertilizer prices have skyrocketed, grain prices have increased and overall input costs have jumped, farmers are starting to see the value in zone management, Arnall explains, noting that it’s one tool in your toolbox to help control costs.

Joe Sullivan farms corn and soybeans near Franklin, Minn., and uses zones to manage the variability in his fields. He’s been using this technique for several years and says that the time and energy he’s invested in developing the field zones, as well as the technology, are definitely worth it.

Season-Long Savings. Sullivan uses variable-rate fertilizer and custom hires the application of phosphorus, potassium and nitrogen to his field zones. He also uses variable-rate planting population.

Prior to making the switch to zones, Sullivan planted seeds at a uniform rate of 32,000 seeds per acre. Today, his population varies from 18,000 seeds per acre to 42,000 seeds per acre.

"My seed costs have actually gone up, because I’m trying to push my most productive areas harder," he says. "In the areas planted with 18,000 seeds, my yields are about 100 bu. per acre to 120 bu. per acre. In the areas with 42,000 seeds, my yields are pushing 230 bu. to 240 bu. per acre."

While Sullivan’s seed costs have increased, his yields have remained the same, which he attributes to bad weather. "We’ve dealt with everything from hail to drought the last few years," Sullivan says, noting that he’s ready for a "more normal" year.

However, Sullivan’s nitrogen costs have gone down as efficiency has gone up. "I used to apply 164 lb. of nitrogen per acre," he says. "With variable-rate nitrogen, we apply 150 lb. of nitrogen, on average."

Sullivan explains that his soils are comprised of about 3% to 5% organic matter, which means that his soils can handle the higher planting populations.

Sullivan says he’s like any farmer. "I’ve got good spots, and I’ve got bad spots, and it can all be in the same strip," he explains. "Zone management helps us make sure that we don’t put too many seeds in soil that can’t support it."

Optimize Profits. One thing that Sullivan battles is iron deficiency chlorosis. To help, he uses a product called Soygreen, which is about $8 per pound. If Sullivan uniformly applied this product at the recommended 2 lb. per acre, he would spend $16 per acre, just to manage iron availability.

By using zones to apply the right amount on the right acre, Sullivan maximizes the crop’s potential.  In the spots that need it most, he’ll apply 3 lb. to 3.5 lb. This technique has cut his costs by about half. For a 100-acre field, Sullivan saves $800.

"I got my investment back within one year, just for the Soygreen application," Sullivan says, noting that he already had the technology, but just wasn’t using it to capacity.

Sullivan’s zones are based off of soil type and years of yield data. His management strategy might be different than most. "I look more at how to optimize each acre instead of how to equalize," he explains. "Most try to increase the lowest yielding areas of their field, but I try to look at how I can be most efficient with inputs on every acre."

Data Supports. Under the leadership of Raj Khosla, Colorado State University Extension precision ag specialist, an economic feasibility study was done.

In the 2004 study, farmers who used site-specific management zones compared to uniform-rate application saved from $7.50 to $17 per acre in nitrogen costs alone, Khosla says. With today’s cost of nitrogen at about $650 per ton, that savings jumps to about $30 per acre to more than $50 or $60 per acre, he says.

Many farmers already have the technology at their fingertips; they just need to sit down and create their zone maps, Khosla explains. 

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