Inching along the dusty field under a broiling sun, Simon Santol tossed garlic bulbs into buckets and chatted with the other stooped-over Mexican workers. The conversation wasn't in Spanish.

Instead, they spoke Santol's native Triqui, or Mixtec, Zapotec or other languages indigenous to the poorest regions of Mexico. Many of the workers can barely get by in English or Spanish.

"It was hard at first," the 28-year-old Santol said in halting Spanish. "We would look for someone who spoke our language and Spanish. Now I have learned a little Spanish. Grace of God."

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Immigrants who have not adopted Spanish or English can struggle to find housing, jobs and fair interest rates, advocate groups say. Navigating the legal system is tricky — sometimes it's difficult just to communicate.

But with worsening conditions at home and relatively rosy reports from family or community members already here, the United States is attracting more indigenous immigrants — people who primarily speak a local indigenous language of Mexico, a country that is Latin America's Tower of Babel. Its government recognizes 162 living languages, plus some 300 dialects.

It's impossible to say exactly how indigenous people have crossed the border. Many are here illegally and would rather not be counted, and immigrant population estimates tend to focus on nationality, not language. But estimates put the number of Mixtec speakers in the United States from Oaxaca alone at 100,000, mostly in Oregon and California's Central Valley.

The stream has grown since the North American Free Trade Agreement opened Mexico to U.S. crops in 1994, straining Mexico's farmers, some experts say.

"Now corn sent by the United States is real cheap, there's no return for us," said Leon Ciovasquez, spokesman for the Indigenous Front of Binational Organizations based in Fresno, Calif. "There's no point in continuing."

One mark of their growing numbers is seen in Oregon's courtrooms.

James Comstock, who leads Oregon's court interpreters service, said that five years ago, his office only handled an indigenous-language case once every few months. Now, he said, there are two or three a week.

He finds interpreters where he can, but some local qualified residents are undocumented and can't be hired. Some interpretation is done by telephone relay through Mexico. And still there are snags.

Comstock recalled a woman whose baby was put in state care. "She spoke no Spanish at all," he said. "It was like talking to a wall. She just didn't understand."

On Oregon's farms, about 60 percent of the Mexican workers are from indigenous populations, estimated Ramon Ramirez, who heads a farmworker union.

Ramirez, who has sent indigenous-language-speaking organizers into fields to hear the immigrants' problems, said many have no idea of their rights.

They didn't use banks back home and usually don't here, he said, making them potential targets for robbery. Car dealers can charge them "outrageous" interest, he said.

The linguistic isolation and a tradition of mistrust and shabby treatment back home have led many to form hometown-based groups.

"Each group usually has a leader, someone the rest can go to," said Daniel Quinones, whose job with the Oregon Employment Department includes monitoring labor law compliance for immigrant workers.

"We know they exist, we hear about them, but most (outsiders) have never been there," Quinones said. "It's their own little culture."

Many of the garlic pickers take their problems to Rene Sandoval Perez, 57, a labor contractor who stays in the field with his workers. Contractors hire and manage the workers for landowners who may never meet them.

"If someone is having trouble talking to a landlord, he can call me and I can say, 'Yeah, he is a good guy,'" Perez said. "We can try to get them to the right doctor. I get the checks from the owner and I give them directly to the workers, `Juan this is yours, Paco this is for you.'"

But many indigenous workers are migratory, taking their chances from job to job, where there may or may not be a Sandoval Perez. Many of the garlic pickers head south. Others stay here to pick hops.

Ramirez's union, Northwest Treeplanters and Farmworkers United, works with the hometown groups. A low-wattage union radio station is scheduled to go on air Nov. 20 — Mexican Revolution Day — with indigenous-language broadcasts detailing labor rights and other topics for farmworkers.

A nonprofit law center has also distributed tapes and other materials in indigenous languages, outlining workers' rights.

Indigenous families also often form their own networks — legal or otherwise — to aid their migration, said Guillermo Alonso Meneses, who follows migration at the Colegio Frontera del Norte in Tijuana, Mexico. Some even have their own immigrant smugglers.

"Ten or 20 years ago you didn't see that," he said.