In 1993, then-President Bill Clinton signed the North American Free Trade Agreement (NAFTA) into law. It marked the first time a trade agreement had been negotiated between two developed nations—the United States and Canada—and an emerging-market country, Mexico. Its original aim was to expand trade and make these three countries more competitive globally. But NAFTA’s various pros and cons have since become hotly contested political talking points centered around some familiar narratives: job-exporting versus job-importing; lower wages versus cheap gas and cheap food; economic growth versus farmer exploitation.

In February of 2017, President Trump told an audience at the Conservative Political Action Conference in Maryland that NAFTA is “one of the worst deals ever made by any country having to do with economic development. It’s economic undevelopment as far as our country is concerned.” Economists and trade experts on both sides of the southern U.S. border disagree about the economic impacts. But smallholder maize farmers in Mexico tend to agree with Trump, at least on this point.

This relentless deluge of cheap, commodity corn has been disastrous for Mexican heirloom corn producers like 56-year-old Floriano Garcia Delfín.

Delfín grows four types of native “landrace”—domesticated and locally adapted—corn on a hectare (2.5 acres) of community-owned farmland in a remote region of eastern Oaxaca called “la Chinantla.” The maize seeds he plants came from his father, whose seeds came from his father, through countless generations. As he drives his pick-up truck—which doubles as a local taxi—past corn fields, cacao groves, and stands of rubber trees, he waves his hand toward the steep hills rising from the river, saying, “We have ancestors buried here from 1000 years ago.”

Like the ancient Mayan civilizations that flourished further south, ancestors of Oaxaca’s 16 indigenous groups worshipped maize gods, performed planting and harvesting rituals, and developed elaborate mythologies about corn. Life revolved around the staple crop, which produced enough food to sustain the farmers who grew it, as well as the elites who oversaw the society.

Although Oaxacans adopted Catholicism centuries ago, corn plants are still considered sacred throughout the state—an agricultural idol of sorts. Delfín says, “Our deep relationship with corn enables us to sustain our families, and it comes with the responsibility that we must treat the corn as we would treat our family. We pray to god when we sow the fields, asking for help in bringing the corn to harvest. Because corn is the giver of life. Corn is our religion.”

Because of NAFTA, that religion is under threat. Before 1994, Mexico limited corn imports to times when its own production fell short of domestic needs. But NAFTA eliminated those limitations while preserving U.S. corn subsidies, totaling $106 billion from 1995 to 2016, in the form of direct payments, crop insurance, price supports, market loss assistance, and other financial supports to American corn producers. American agribusiness giants, meanwhile, took advantage of those changes to begin dumping millions of metric tons of commodity corn from the U.S. on the Mexican market at below production costs.

During the first decade of the agreement, U.S. corn exports to Mexico quadrupled, while the price of domestically-grown corn in Mexico crashed by nearly 70 percent. No longer able to support their families by selling their excess corn, an estimated 2 million farm workers abandoned the Mexican countryside for the big cities, looking for work. Unable to find jobs in their country, half-a-million Mexicans a year migrated to the U.S., contributing to a 75-percent increase in illegal immigration from Mexico in the five years after NAFTA took effect.

Though rates of undocumented migration from Mexico have slowed dramatically in recent years, this massive shift helped pave the way to today’s fraught debates over immigration.

Laura Carlsen, director of the Americas Program for the Washington, D.C.-based think tank, Center for International Policy, is surprised that the exodus wasn’t even larger. Before NAFTA went into effect, she says, the U.S. Trade Representative’s office told her that small corn producers in Mexico would choose to become workers in new industrial corridors because their farming methods weren’t efficient, they couldn’t compete on a global scale, and it would be difficult to extend government services to the remote areas where native corn thrives.

Carlsen says she remembers asking, “Seriously? You’re going to relocate 3 million corn producers into some hypothetical other part of the economy, not to mention some other part of the country?” But in reality, “There was less displacement than we anticipated, because everybody—including us—underestimated the cultural and spiritual ties to the land.”

Renée Alexander

This farmer grows corn and cacao in Plan de los Flores, a village in la Chinantla, Oaxaca

As producer prices plummeted in response to the flood of imports, “…instead of moving out of corn, as a rational choice economists would predict, and migrating to the cities and getting jobs in a booming industry, which didn’t happen, [Mexican producers] actually planted more corn in a lot of places,” says Carlsen. “Because corn is the safety net. If you don’t have anything else, you can still eat.”

In 2006 and 2007, when the American economy cooled just ahead of the global recession and automobile manufacturing plants started opening in Mexico (likely a delayed result of NAFTA), more Mexicans began returning home than entering the U.S. But they couldn’t easily return to the corn fields to continue the tradition of their ancestors, because the Mexican government continued (until this year, when it looked to Brazil) to increase subsidized U.S. corn imports.

Furthermore, according to heirloom corn farmer Delfin, government officials actively encourage Mexican farmers to switch from their ancestral native landraces to hybridized corns that produce higher yields.

He says, “Companies create new, ‘improved’ versions of corn and sell it to the Ministry of Agriculture, which gives it to politicians in the ruling party. Those politicians come to the pueblo and ask, ‘How many campesinos here grow corn?’ They give each farmer a bag of seed and promise better yields, in exchange for votes. If the yield does increase, the farmers will continue to plant the hybridized corn, leading to less diversity.”

Dr. Martha Willcox, Maize Landrace Improvement Coordinator for CGIAR (Consultative Group for International Agriculture Research) in Oaxaca, concurs.

“Farmers tell us the hybrid corns just don’t make the tlayudas and posole that they love, so many will grow their own little plot of native corn [for home consumption].”

Native corn varieties often perform better than hybridized varieties in areas with poor soil, limited rainfall, mountainous landscapes, or high pressure of crop disease, says Wilcox. This is because hybridized varieties are designed for mass cultivation in flat, irrigated fields that can be machine-harvested, whereas native corn varieties have been individually selected from each harvest from the very fields they will be replanted in—and harvested from—by hand.

Delfín says, “With native corn, I can plant it today and leave it alone, and it will grow on its own. I don’t need to use any chemicals.”

But native corn, and the ancient techniques still used to cultivate it, don’t always produce enough food for farmers to feed their families and livestock on the limited land they have available, much less enough excess to sell in the market. Because of the price differentiation between native corn (6 to 12 pesos per kilo) and commodity corn from the US (4 to 5 pesos per kilo), it is tempting for farmers to sell the higher-value native corn in the local market and buy the cheaper commodity corn to feed livestock. And while so-called transgenic corn can’t legally be planted in Mexico, it is sold all over the country as animal feed, and there is nothing to prevent people from eating the corn themselves, or planting it.

Flavio Aragon Cuevas is working to change this dynamic. As a lead researcher of agricultural genetic resources who curates the main seed bank in Oaxaca for INIFAP (National Institute for the Investigation of Forestry, Agriculture, and Fisheries), he and his team of agricultural technicians act as native corn evangelists. They visit local villages to promote a “family first” model, which involves feeding your family and livestock first with the native corn that you grow, and selling only surplus corn on the market. His team also teaches farmers how to increase yields and cut costs.

Cuevas also curates the main seed bank at INIFAP headquarters in Etla, Oaxaca. In addition, he has set up 11 local seed banks throughout the state, with plans to create 15 more.

Delfín keeps his community’s local seed bank on his front porch, in tightly-sealed plastic barrels. The seed bank serves eight surrounding villages, and there is no fee to join. Each farmer deposits a year’s worth of the best seeds from each harvest, usually five kilos (a little more than 11 pounds) per variety. Even farmers who don’t deposit can get seeds from the bank in the event of a crop failure, with a promise to bring back double the amount of their best seeds after the harvest.

In recent years, Oaxacan chefs have discovered the corn exchanges, and many are eager to learn how to cook with some of the 35 different varieties of heirloom corn grown in the state. Other market-makers include artist Jonathan Barbieri, founder of the Pierde Almas mezcal brand, which started making ancestral corn whiskey last year.

Besides coordinating corn exchanges, Ortiz amplifies Cuevas’s field work by connecting farmers with agricultural technicians, funding biodiversity research, and promoting public policies that support native corn cultivation.

“Commodity corn doesn’t work where plots are small; they are more successful in flatter coastal areas,” says Ortiz, adding that Mexico’s Ministry of Agriculture should promote heirloom corn, using Oaxaca as a model for the entire country.

Recent political developments offer an additional glimmer of hope. Andrés Manuel López Obrador, who won Mexico’s Presidential election on July 1, has signed on to the “Plan de Ayala 2.0,” which calls for public policies that support farmers directly and guarantee the rights of campesinos. He has promised to help farmers seek food self-sufficiency by providing free fertilizer, subsidies, credit for agriculture and livestock, and the planting of a million hectares of fruit and timber trees in Southern and Southeastern Mexico.

Willcox from CGIAR has already started doing that, thanks to a deal she helped broker between dozens of local farmers and Masienda. The U.S.-based company sells heirloom corn from Oaxaca, as well as tortillas and masa made from Mexican maize that are much beloved by American chefs.

“When Masienda was looking for native corn. Flavio (Cuevas) and I went out to farmers to ask if they had any maize to sell,” says Willcox. “We told them, ‘We don’t want you to sell your food; but do you have extra that you can sell?'”

Mexican corn farmers are understandably wary of people offering to buy their corn now and pay for it later. “Usually, a guy will drive into a village with a truck and offer a low price for their excess grain, just when the farmers are the most vulnerable, financially,” says Willcox. “The harvest is in, and they need to pay for labor. Sometimes these buyers—known locally as ‘coyotes’—simply don’t pay. They tell the farmer, ‘I’ll be back next week,’ but they never come back. So the farmers lose trust, and they only sell their dirty corn to people who show up in trucks.”

In order to meet export requirements and Masienda’s standards, Willcox and Cuevas needed high quality grain that was fungus-free, cleaned, and bagged properly. Willcox says, “Farmers know what clean grain is, and they’re not willing to sell it for cheap,” so they offered a fair price.

“The farmers knew Flavio personally, so they were willing to take the risk,” says Willcox. “We were able to put together 50 kilos here and 200 kilos there, and we were able to sell 10 tons of corn to Masienda. It was really the relationships that Flavio built over the last 30 years that allowed us to walk in and buy their corn.”

She notes, “People are now coming here from Canada and Russia, looking for native corn. Chefs are willing to pay more for exceptional quality maize, so there are farmers who are very interested. But we still have the same problems we started with: not enough land to grow more corn, and no easy way to connect the farmers with somebody in another country who wants to buy their product.”

Most Mexican corn farmers  can’t afford to open a bank account that can accept international payments, or to maintain a minimum bank balance, or to hire an accountant to prepare and submit tax documents. So Willcox is exploring creative financing options, such as organizing 30 to 50 farmers to create joint bank accounts and sell grain collectively.

In addition, Willcox is working with Cuevas, Ortiz, and others to develop a third-party certification  process and trademark of authenticity to prevent the cultivation and commercialization of Mexican native corn elsewhere. They want landrace maize to be recognized as intellectual property that took hundreds of years to develop.

Masienda founder Jorge Gaviria says, “Martha let us know that this was important, and we were on board right away.” As a result, Masienda’s online bodega includes the verbiage, “By accepting delivery of the landrace maize … associated with this order, recipient acknowledges and confirms that this Masienda product shall not be propagated, cultivated or resold….”

Masienda’s commercial customers include name chefs like Cosme’s Enrique Olvera, Frontera Grill’s Rick Bayless, and Oyamel Cocina Mexicana’s José Andrés. Gaviria says purchasing volumes range dramatically. “We have some folks who are buying a couple pallets of corn at a time, while some restaurants want to run a special and buy a single 55-pound bag.”

Most of his commercial customers nixtamalize the native corn by hand. The time-consuming process greatly increases the nutritional value and digestibility of dried corn. It involves simmering the kernels in a solution of water and lime (the mineral, not the fruit), leaving it to sit overnight, rinsing it, then grinding it to make masa, which Gaviria describes as “…a blank canvas for many different things, including tortillas, tamales, tlayudas, and thickeners for soups and moles.”

One of those customers, Chris Pastena, purchases 1,500 to 2,000 pounds a month for his Oakland, California restaurant, Calavera. The Oaxacan-themed eatery employs five tortilla makers, all from Mexico, ensuring one person is making tortillas constantly during each shift. Still, they sometimes have trouble keeping up with demand, says Pastena, who is currently on the lookout for a hand-cranked tortilla-making machine.

“Making our own nixtamal is a commitment,” he says. “But it’s worth it to us because it’s fantastic corn, and we want to support growers in Oaxaca. We are very proud to be sending a thousand dollars or more each month to Mexican corn farmers.”

Heirloom maize advocates hope that their efforts to build sustainable markets for native corn will entice the next generation of Mexicans to grow it.

“You can store maize seed from one to three years, but eventually you have to plant it and harvest it to keep it going,” says Willcox. “We see farms with beautiful maize that top chefs want to buy, but the farmer is 80 years old, and all his kids live in the U.S. If someone doesn’t come back to Mexico, that maize is lost, and there’s no way to get it back.”

Ortiz from CONABIO concurs: “Older farmers worry that the next generation won’t continue the tradition of growing their own food. This is the main problem with agriculture in Mexico, whether you’re growing corn, or coffee, or any crop. Hopefully the story of the new generation of maize farmers will be different. Previously, this was a problem with mezcal, but now that there is a market for mezcal, the kids are coming back to carry on the family tradition because they can make money doing it.”

Willcox says she has seen anecdotal evidence that their efforts are working. “In villages that were not growing enough corn to feed the local population, we have seen some people turning down six-month agricultural contracts in the U.S. because they thought they could make enough money as corn farmers.”

She continues, “I will say we have been successful when we have the children of these farmers coming back to farm. If we don’t do something, this way of life will be lost in 20 years.”