In the early 2000’s during the last major dip in the agriculture economy, precision programs – more specifically, variable-rate fertilizer recommendations — were among the first victims of cutbacks that growers employed in an effort to cut costs. With concerns running high about a significant retreat in crop prices in 2014, could history repeat itself?
A report in ag retailer publication CropLife magazine, “2014 State of the Industry,” indicated that retailers are bullish on their precision programs, in large part because they are more established and collaborative with grower customers.
Bill Moyer, owner of agronomy consulting firm LFB Solutions, Coldwater, MI, is among those who feel confident that precision programs have staying power. In part, it’s because of his approach to variable rate fertility.
Since the beginning, Moyer has bought into the concept of “maximum economic yield,” an approach he first encountered during his days managing a fertilizer retail business some 20 years ago.
“At the time, I thought that was a tremendous concept,” says Moyer. Maximum economic yield is about creating a recommendation that considers tillage practices, planting practices, and more efficiently uses nutrients by placing them where they are needed and not placing them in areas where they are already high — but that is still going to deliver a payback to the grower. “I look at precision agriculture practices as a tremendous way to carry that concept even further.”
Moyer says that creating a recommendation in the spirit of maximum economic yield requires two things – a thorough knowledge of the soil and yield data. “There are certain areas of the field that will have more water holding capacity, or nutrient holding capacity,” says Moyer. “Why not drive those areas of the field as far as they can go?” Conversely, identifying what areas of the field that cannot be maximized through fertility increases, or which already have adequate nutrient availability, will tend to balance out the total field load of fertilizer.
“I look at variable rate capabilities as being able to address high and low production areas, maximize input across the field and ultimately save money. That said, you don’t want to drop fertilizer application on the poorer areas of the field to the point that they underperform, but it’s simply not necessary to pour a bunch of money into them unless things can be improved measurably.”
Moyer notes that soils in his area feature significant variability, making the one size fits all fertility approach particularly detrimental.
Moyer says the approach to soil understanding doesn’t particularly matter – identifying mangement zones and/or grid sampling can be the basis for a successful program. Actual soil sampling, combined with data from historic soil type maps, create a solid base of data. Finally, the addition of yield data – ideally, multiple years – ground truths the program and allows the agronomist to fine tune recommendations.
Ultimately you have to start looking at yield monitor data from multiple years, says Moyer, because taken individually or in small samples, outlying variables can push the yield number to a positive or negative extreme. “When you are looking at multiple years of data, you can more confidently identify patterns in production that are simply too significant to ignore,” he says. A consistent replication of a pattern may point to the need to redraw management zones.” In time, with enough corroborating data, a field may prove to be a good candidate for variable rate seeding to even further maximize economic yield.
Moyer says that growers at the upper mid range of acreage – 1000 to about 2500 acres – are finding justification in using variable rate fertility programs “A few dollars and acre here or there adds up when spread over that amount of acreage,” says Moyer. “Variable rate fertility and planting are relatively inexpensive compared to a lot of things we do on farms.”
Moyer feels strongly that his more experienced precision clients – those in a program for 3 to 4 years already – are not in danger of walking away from the groundwork they have laid.