The seed money comes from men who couldn't make a living here and left for California, the idea from one of the women they left behind.
Then Sanchez got busy in her backyard. She started plowing her husband's wire transfers into a waist-high patch of nopal. The paddle-like cactus leaf has a succulent taste and, she suspected, a market far beyond impoverished Oaxaca state. Soon other peasant women joined her, investing cash from their men in California.
Nearly 2,000 miles away, Erasmo Alonzo imagined that the wages of his back-breaking labor were buying a TV, a washing machine and indoor plumbing. On his first visit home, "he did not find any of those things," Sanchez recalled. "Look outside," she told him, proudly pointing to her rows of nopal. "That is our future."
With additional financing from migrants in California and the Mexican government, Sanchez's co-op is building a food-processing plant that will employ dozens of this Zapotec Indian community's 5,750 inhabitants. Starting this summer, the co-op's 134 growers plan to supply 10,000 1-pound jars of organically grown, pickled cactus each week to an expanding specialty-food market in the United States.
The venture is a village-level display of the power of remittances, the billions of dollars that migrants earn in rich countries and send home to sustain their kin. It is part of a search by struggling communities, international aid agencies and governments for ways to harness this flow to alleviate the poverty that drives people to migrate in the first place.
Migrants have been sending money home, in one form or another, for centuries. But only recently have economists recognized its significance. Today, remittances are the largest, fastest-growing and most reliable source of income for developing countries. Poor nations reported $167 billion in receipts from overseas workers last year, according to the World Bank, more than all foreign aid. Including unrecorded transactions, the bank estimates that the total exceeded $250 billion.
This giant transfer of wealth crisscrosses the Earth in millions of trickles, a few hundred dollars at a time, sent by workers who have assumed much of the burden of Third World development. Their remittances — private aid from the poor to the poorer — offer a rare chance to accumulate savings; invest in schooling, housing or a small business; and rise into the middle class.
At least $39 billion flowed out of the United States last year, wired home by legal immigrants as well as many of the estimated 12 million people whose undocumented status and growing numbers have provoked a furious debate over immigration policy.
According to the World Bank, the number of international migrants swelled from 120 million to 175 million during the 1990s, and the sums they send home each year have more than tripled in this decade.
"Close to a billion people, one in every six on Earth, may receive some support from this lifeline," said Dilip Ratha, a senior World Bank economist. "The scale is huge, maybe bigger than we think, and potentially transforming."
One end of the lifeline is the field near Salinas where Erasmo Alonzo started work before dawn one morning.
A wiry man with a bushy mustache and gnarled fingers, Alonzo stood out among the 15-member Latino work crew as they stepped off a white bus, stretched their muscles and spread out across the furrows. He was by far the oldest. The others called him tio, or uncle.
For eight years, he had been stooping over those fields for up to 10 hours a day, reaping a chronic back pain that felt "like an ugly wound." But on that July morning, he moved as nimbly as his youthful co-workers as they extracted row after row of romaine lettuce from the soil with 12-inch knives, whittled away the dirty outer leaves and tossed the heads onto a conveyer belt at a rate of 17 per minute, a precision ballet that left their white plastic aprons splattered green and two 400-pound tractor-borne boxes filled with produce.
Alonzo had been off the day before, a Sunday, and devoted part of the day to the ritual that defined his purpose in America: wiring money home to Mexico.
"It is a struggle to get a decent amount together, but I send $500 every two or three months," he said. On this Sunday, he had wired home $200 and paid 10% in commission to a licensed agent of AFEX, a worldwide transfer company based in Chile. From the strip mall jewelry counter where the transaction took place, he had called his wife in Ayoquezco by cellphone to tell her she could pick up the money the next day.
Fed by millions of such transactions, Mexico's annual remittance inflow has doubled since 2002 and reached $20 billion last year, second only to petroleum as a generator of wealth for the country.
Other developing nations also depend heavily on their migrants' money. Brazilian laborers in Japan send home more than $2 billion a year, out-earning their country's coffee exports. Remittances bring in more than tea exports do in Sri Lanka and tourism does in Morocco. In Jordan, Lesotho, Nicaragua, Tonga and Tajikistan, they provide more than a quarter of the gross national product.