POLK CITY — It takes twice the fossil fuels to run vehicles and equipment to run only corn and soybeans on fields for four years as it does to mix in small grains for two years of that cycle.
That’s one of the benefits of crop diversity and farming oats and other small grains mentioned at a field day held last week at the farm of Aaron and Nicole Lehman near Polk City last week.
Representatives from Iowa State University gathered on the Lehman farm to talk with several dozen farmers about the benefits and some techniques associated with farming small-grain products. While the grain discussion was primarily about oats, a crop that can easily “stand in” for corn and soybeans in Iowa as part of crop rotations, there were plenty of other topics raised both during planned presentations and by farmers who asked questions.
The field day was arranged by Practical Farmers of Iowa.
Dr. Matt Liebman, an ISU agronomist, was the presenter who addressed the reduction of fossil fuel usage.
“The reduction in fossil fuel use is in the three-year and four-year rotations,” Liebman told the group. “If you do the math, I think you’ll come up with 56 percent less fossil energy used in the corn-soybean, oat-red clover three-year system.”
In slides Liebman provided to the Newton Daily News, a four-year, corn-soybean, oat-alfalfa-alfalfa rotation would consume 62 percent less fossil energy. Much of the savings are from not having to put oats through the drying procedures needed on larger grains.
Liebman also talked about reduced costs of production through small grain rotations. Expenses for supplies such as seed, fertilizer, pesticides and fuel are lower in the three-year and four-year rotations than in the two-year system.
“If farms borrow money to cover expenses for these inputs, they would need to borrow less money if they used the longer rotations,” Liebman said.
These were only two of many concepts covered by Liebman, ISU graduate student David Weisberger, Lehman and others. Several of the ISU representatives pointed out the unnatural strain monoculture agriculture places on soil and land conditions, as aerial photos 60 years old or older would reveal a more diverse system of small fields filled with a greater variety of crops and land uses.
The March-to-July cycle of oat planting is not without its hazards, Liebman said. A massive hailstorm happened in July 2013 the night before a harvest was set to take place, causing significant losses to the crop.
Weisberger covered a large number of small-grain aspects, including ideal climate conditions. The March-to-July cycle works well in northern Iowa for small grains not only because these are not hot-weather crops, but also because the day-night temperature variance is greater in the northern third of the state than it is in, say, Chariton or even Jasper County.
“This is important because spring cereals like oats do not do very well in hot weather, and do even worse when nighttime temperatures don’t cool down,” Weisberger said.
There was also discussion of the importance of treating or not treating oats and other small grains with chemicals or compounds. Bruce Roskens spoke about buyers not buying oats that have been desiccated with glyphosate.
Lehman allowed the group to set up on his lawn under large shade trees, and his barn was used as well. A meal was served as part of the field day.
The host farmer not surprisingly, sounded much more down-home in describing what he’d learned from the more scientifically spoken ISU representatives, but the farmers in attendance seemed to appreciate both approaches and the information provided.
“If you think it’s time to do something in a field, go fishing for the weekend, then come back and do it,” Lehman said.
Contact Jason W. Brooks at 641-792-3121 ext. 6532 or jbrooks@newtondailynews.com