Farm runoff also fueled toxic algal blooms that fouled parts of Lake Erie in recent years. And nitrous oxide — a byproduct of fertilizer use — is a potent greenhouse gas, carrying a planet-warming punch 300 times larger than the same amount of carbon dioxide. Farms make up about 9 percent of US greenhouse emissions, and they’re the source of nearly four-fifths of the nitrous oxide output, according to the Environmental Protection Agency.
When EDF helped the sprawling retailer Walmart calculate its carbon footprint, it found the biggest single chunk wasn’t the fuel burned by its delivery trucks or the steel and concrete in its thousands of stores; it was the nitrogen fertilizer used to produce the food it sold, Parkhurst said.
“Even small changes in the amount of N2O that’s generated form your fertilizer use has a huge environmental benefit,” Parkhurst said. “So you can have a big bang for a small buck.”
RELATED: Genetic Tweak Could Help Save Millions of Tons of Corn From Deadly Toxin
The promise of precision agriculture has been out there for more than 20 years, said David Bullock, an agricultural economist at the University of Illinois. But it’s taken time for the technology to catch up to the promise, and there’s still a lot of work to be done “to know what to do where in the field.”
“All kinds of companies are trying to sell farmers stuff, so I think a lot of times they’re wary of whether they’re being sold something worthwhile or not,” Bullock said. “I would say there’s a long way to go.”
He said some companies have entered the field using algorithms that are outdated or based on weak data, or make claims that aren’t well-grounded in science.
To help remedy that, Bullock and his brother Don — an agronomist at Illinois — have been experimenting with a grid of hundreds of patches of nearby farmland, tweaking fertilizer amounts on each patch to match it with yields under different conditions. They monitor how much seed gets spread, what the weather does, the topology of the patch, and the moisture and water flow in the soil.
“The hope is we can use those numbers to start telling folks how to farm better,” Bullock said. “But it’s hard, because there’s not enough data. We’re looking for tools that can gather data cheaply and be useful. That’s part of the research challenge.”
RELATED: Methane-Eating Microbes Produce Food for Farmed Animals
Despite the growth of massive agricultural corporations, more than 90 percent of farms remain family-owned operations, Parkhurst said. Many of them historically have held hard numbers about their costs and yields close to the chest. They’ve been open to sharing the data modern implements collect with manufacturers and universities, but generally reluctant to open up to environmental groups or food companies that buy their products, he said.
Schmidt said farmers need something in return for that data, which he said could be traded like the commodities he grows.
“We would love to have a software firm come in here and develop algorithms that look at a 6-year history and tell us, ‘Based on this nutrient, based on this weather or climate, based on your harvest data, here is with 80 percent accuracy your best move for the next cropping season,’” Schmidt said.
“I want to be able to do that," he added. "I don’t want somebody sitting in a corporate office in St. Louis or the Quad Cities or Chicago doing that. Because at the end of the day, they will better their bottom line, but this is my data. I want to be able to better my bottom line.”
WATCH: Are Any Foods Natural Anymore? GMOs Explained.