NUTRIENT-PRODUCING MICROBES WIN OVER MINN. FARMERS, BUT SKEPTICS DOUBTFUL By Dan Gunderson | MPR News MOORHEAD — On his south-central Minnesota farm, Colin Wegner adds bacteria to the corn seeds he plants, and cuts back on the synthetic nitrogen fertilizer traditionally applied to corn. The live bacteria are selected for their ability to pull nitrogen out of the air. “They live on the corn roots; the corn root releases sugars and carbohydrates throughout the growing season,” Wegner said. “And what the microbes do is they convert nitrogen out of the atmosphere, and they convert it to plant-available ammonia.” Wegner is a fifth-generation farmer, and he’s so convinced microbes are the future of farming that he became a sales representative for Pivot Bio, the company that makes the bacteria he uses on corn.
Symbiotic process
The early 1900s discovery of a process to create synthetic nitrogen fertilizer revolutionized agriculture. But the process has a big carbon footprint, using large amounts of natural gas. And nitrogen fertilizer applied to soil but not used by plants can leach into water or turn into nitrous oxide gas and escape into the atmosphere. Nitrous oxide accounts for only a small fraction of worldwide greenhouse gas emissions, but according to the Environmental Protection Agency, the impact of 1 pound on warming the atmosphere is 265 times that of 1 pound of carbon dioxide. There are billions of bacteria in soil. Some already produce nitrogen in a symbiotic relationship with plants such as beans and other legumes. Companies are identifying and reproducing the best nitrogen producers to add to corn and other crops. Some are genetically edited to enhance nitrogen production. “We know that our microbes have the capability of producing perhaps 40 or more pounds nitrogen equivalent for most growers,” said Pivot Bio Vice President Dan Poston. “Our goal is constantly to move that number up with new and improved microbes.” Farmers are interested, and they’re buying. Pivot Bio released its first product in 2019, and this year the company reported that the microbes it sells were Page 32 – West Central Tribune – November 2023
Dan Gunderson / MPR News
Companies are identifying and reproducing the best nitrogen producers to add to corn and other crops.
used on 5 million acres across the U.S., while revenue grew 60%, surpassing $100 million. And Pivot Bio is only one of many companies entering this potentially lucrative market.
Skeptical analysis
But skeptics abound. Soil scientists at a number of universities across the Midwest tested some of the bacteria supplements. “So it turned out that the performance wasn’t all that great,” said Dave Franzen, an extension soil specialist at North Dakota State University. Franzen authored a paper compiling research on nitrogen-producing bacterial supplements at a dozen Midwestern universities. “I think the most important thing for farmers to get out of it is, don’t believe everything you hear,” he said. Franzen tried to buy nitrogen-producing microbes to test last year, and the products were sold out. He was shocked farmers were so quick to go all in on what he believes is an unproven technology. “How could you do this without seeing some kind of really positive research from people where their retirement program isn’t tied to this? But they bought it all up. And that was crazy,” he said.
