Craig Shaw knew he needed to get the most from every dollar he spent on inputs, but in some cases, the more he spent, the more trouble he bought.
An emphasis on maximum fertilizer use was helping the grain farmer from Lacombe, Alta., achieve bin-busting yields, but the parts of his farm that had higher organic matter were also yielding something else – crops with lodging problems that made harvest difficult and left him with poor grain quality.
“That was actually reducing the margins from each acre,” he said.
Read Also
VIDEO: Green Lightning and Nytro Ag win sustainability innovation award
Nytro Ag Corp and Green Lightning recieved an innovation award at Ag in Motion 2025 for the Green Lightning Nitrogen Machine, which converts atmospheric nitrogen into a plant-usable form.
“At that point we knew we had to manage the variability within the fields to get the most from the land. We were wasting our inputs in our best soils.”
Shaw’s research into variable rate application led him to satellite imagery, which he felt might be the most effective way to analyze his farm’s fields.
He enlisted the help of Farmer’s Edge Consulting of Pilot Mound, Man., which combines remote sensing in the form of infrared satellite imagery with soil sampling to create a comprehensive field analysis that is further enhanced by comparing the technical data with a producer’s practical experiences in the field.
Wade Barnes of Farmer’s Edge said proper soil sampling is critical to compiling useful field data.
“We need to understand more than the mobile nutrients – nitrogen, sulfur,” he said.
“We need to know about organic matter, cation exchange capacity, salt and pH to understand just what the soil is capable of delivering in any given area (of the field).”
Barnes also analyzes micro-nutrient availability, looking at copper, zinc and boron.
Barnes uses that data, as well as regional agronomy and climate information, to develop yield goals for the fields.
“When you have this kind of knowledge you can get away from shotgun solutions to fertilizer application,” he said.
Barnes feels variable rate application of crop inputs can deliver significant profits.
“You stop overfertilizing some areas that never will deliver high yields. You also stop overapplying in areas that will end up lodging and creating headaches at harvest.”
Barnes said variable rate technology also allows producers to push areas that are capable of producing high yields.
Limiting nutritional factors can be identified and remedied at seeding or through additional applications of the missing elements.
Shaw said in some cases the soil can’t meet yield expectations. If so, yield goals can be lowered and fertilizer rates cut to match the land’s productivity.
Barnes said reduced fertility costs producers $5 to $45 per acre in yield loss.
“Variable rate application typically won’t save you much in nitrogen costs, but it’s some of the other inputs that add up. Things like (phosphate) and sulfur.”
He said variable rate management can increase the per acre margins on a typical canola crop by $25 to $185.
Shaw used both variable rate and single rate applications on his farm last year and found little difference in seeding costs on his average fields.
However, he saved $35 per acre on his marginal fields and highly productive land.
“We still have a lot to learn about our fields and variability,” Shaw said. “What have we have learned? Variable rates pay.”
