A new study from Cornell University is reigniting one of the oldest arguments in agriculture. Do we actually need synthetic fertilizer to feed America, or have modern farming systems simply forgotten how to use the fertility nature already provides?
The Cornell researchers reached a startling conclusion. According to the study, the United States already produces enough recoverable nutrients from human waste, animal manure, and food waste streams to theoretically replace all synthetic nitrogen fertilizer currently used on American farmland. The researchers estimated that existing waste streams could provide roughly 102 percent of the nitrogen needs of U.S. agriculture if those nutrients were properly captured, processed, and redistributed.
Supporters of regenerative agriculture see the study as proof that industrial agriculture has become unnecessarily dependent on synthetic chemicals. Critics, however, argue the conclusions are being viewed through rose-colored glasses and ignore the brutal economic and productivity realities of modern food production.
At the center of the debate is a simple but uncomfortable question. If natural fertility is truly sufficient, why did the world adopt synthetic fertilizer in the first place?
The Cornell Argument
The Cornell study argues that America does not suffer from a lack of fertility. Instead, the researchers say the country suffers from a logistics problem. Nutrients already exist in massive quantities, but modern farming systems are geographically disconnected. Livestock operations, grain farms, and urban waste systems are often separated by hundreds or thousands of miles.
Regenerative agriculture advocates believe the answer is rebuilding biological nutrient cycles rather than continuing dependence on fossil-fuel-based fertilizer systems.
Regenerative farmer Mollie Engelhart wrote that “the problem is not resource scarcity. The problem is logistics.” She argues that healthy soil already contains enormous reservoirs of nutrients that can be unlocked biologically through fungi, microbes, livestock integration, cover crops, and reduced tillage.
USDA soil researcher Rick Haney has become one of the leading voices supporting this idea. Haney argues decades of chemical-heavy farming have damaged soil biology to the point that farms now require increasing fertilizer simply to maintain yields.
“Our mindset nowadays is that if you don’t put down fertilizer, nothing grows,” Haney said. “But that’s just not true, and it never has been.”
Note from the Editor, a Kentucky farm boy: Haney is clearly not a farmer.
Haney argues that excessive tillage and chemical use have destroyed organic matter and microbial life that naturally cycle nutrients through soil ecosystems. He believes regenerative practices can restore those systems over time while reducing fertilizer costs dramatically.
“We’ve had guys who told me, ‘You saved me $60,000 in fertilizer costs last year,’” Haney said while discussing farmers who adopted soil health practices.
Supporters also point to rising fertilizer prices as evidence that synthetic dependence has become dangerous. Climate Farmers reported that fertilizer prices increased roughly 80 percent after 2020, partly due to global instability and disruptions involving Russia and Belarus, two major fertilizer exporters.
French researcher Fabien Esculier has also argued that modern societies are wasting enormous quantities of recoverable nutrients. Esculier, who studies agricultural reuse of human waste, said nations now spend huge amounts of money destroying nitrogen in wastewater treatment plants while simultaneously manufacturing synthetic nitrogen fertilizer using fossil fuels.
“It is possible to do without synthetic fertilizers,” Esculier argued, while warning that dependence on fossil-based fertilizer systems creates food security vulnerabilities.
The Skeptical View
Critics of regenerative agriculture say the movement often oversells what is realistically possible at industrial scale.
One of the strongest arguments comes from researchers studying synthetic nitrogen itself. According to data cited by Our World in Data, synthetic nitrogen fertilizer now supports approximately half of the global population. Researchers estimate that between 44 and 48 percent of the world’s people rely on food grown using synthetic nitrogen fertilizer produced through the Haber-Bosch process.
Without synthetic fertilizer, some estimates suggest the world population that could be sustainably supported might fall from more than 8 billion to roughly 4 billion people.
Critics argue this is not merely a policy preference. It is basic math.
The MIT Climate Portal notes that synthetic fertilizer dramatically increased agricultural productivity by allowing far more food to be produced on the same amount of land. Without it, yields would likely decline sharply, requiring far more farmland to produce equivalent food supplies.
Opponents also argue that regenerative advocates frequently understate transition risks. The Guardian recently documented farms experiencing severe yield collapses after reducing chemical inputs. One British farm reportedly saw wheat production fall from more than 7 tons per hectare to just 1.5 tons before partial recovery years later.
That kind of collapse may be survivable for niche premium farms selling high-priced products, but critics argue it would devastate commodity agriculture.
Another major concern is profitability. Modern farmers often operate on extremely thin margins. Critics say farmers cannot simply gamble on lower yields and uncertain biological systems while still paying land loans, equipment costs, taxes, and payroll.
Even regenerative advocates admit the transition period can be financially dangerous. Climate Farmers warned that “cutting out fertiliser doesn’t happen overnight” and that sudden transitions can lead to “reduced yields and income.”
There are also serious logistical concerns. Manure and compost are bulky and expensive to transport compared to highly concentrated synthetic fertilizer. Critics argue that even if America technically produces enough recoverable nutrients, redistributing them nationwide would require massive infrastructure investment and enormous transportation costs.
Environmental critics raise additional concerns about contamination. Human waste streams may contain pharmaceuticals, hormones, antibiotics, and chemical residues. Even organic farming systems frequently use manure originating from industrial livestock operations where upstream chemical use remains common.
Perhaps the biggest criticism is that regenerative agriculture may work best at smaller scales or in mixed farming systems that are difficult to replicate across modern industrial agriculture.
Critics argue there is a reason humanity embraced synthetic fertilizer in the first place. Natural fertility systems existed for thousands of years, yet global crop yields remained relatively low until synthetic nitrogen arrived in the early 20th century.
From this perspective, synthetic fertilizer was not some tragic mistake. It was one of the greatest agricultural breakthroughs in human history.
That does not mean critics reject regenerative agriculture entirely. Many support reducing fertilizer overuse, improving soil biology, and lowering chemical dependence where possible. But they argue the idea that modern civilization can fully abandon synthetic fertilizer without major reductions in food production is highly speculative.
The real debate may not be whether regenerative agriculture has benefits. The real debate is whether modern societies are willing to accept the lower yields, higher labor demands, logistical complexity, and potential food price increases that could come with abandoning synthetic fertilizer systems that currently feed billions.
