The border crisis is jeopardizing the nation’s food security as migrants trespass through farmland, contaminating crops, two Arizona farmers with fields near the southern border told Fox News. 

"There's obviously a food safety concern because our fields are monitored and audited and tested for different pathogens," Pasquinelli Produce Company President Alex Muller told Fox News. "If there's somebody that walks into our field and then we don't know about why we put up flags and kind of mark it out and we don’t harvest that." 

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"That hits the bottom line," Muller said. "It's not sustainable. It's not good for the country." 

Farmer gestures toward the US-Mexico border

Alex Muller, whose farmland lines up against the U.S.-Mexico border, said the unfinished border wall gaps amid a migrant influx jeopardizes food safety. (Megan Myers/Fox News)

Yuma — the country's agricultural leader in leafy green production during the winter months — provides about 90% of the nation’s supply of romaine and iceberg lettuce, according to the Department of Agriculture. It supplies around 9 billion servings of leafy greens per year, but farmers fear they will lose crops as more migrants pass through the border wall's gaps and into their fields.

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"We've gotten a fair amount of traffic through and around our fields and through the whole entire Yuma Valley," a fifth-generation farmer, Hank Auza, said. His properties cover several thousand acres with fields near Morelos Dam, where gaps in the border wall remain. 

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Then-Gov. Doug Ducey ordered construction of a container wall in August to plug those holes. But the state agreed to remove the shipping containers by early January as a result of a federal lawsuit.

"Where the gaps are opens up to more farm ground for them to walk across," a fifth-generation farmer, Hank Auza, told Fox News. "We spend hundreds of thousands of dollars just on our farm for food safety."

Yuma migrant crossings increased 171% between 2021 and 2022, according to Customs and Border Protection. About 1 million migrants have crossed Arizona's southern border during the Biden presidency. 

"This is the largest humanitarian disaster we've had in this country," Auza said. "And part of the country is happy that it's happening. I don't get why."

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A neighboring farmer lost nearly $100,000 after a handful of migrants hid on his land for a week, Auza told Fox News. He couldn't harvest the affected crops in case they were contaminated with pathogens that could lead to foodborne illness. 

Migrants walk through farms in Yuma, Arizona

Migrants walk through farmland after passing through the unsecured U.S.-Mexico border.  (Courtesy: Alex Muller)

"Now you start failing food safety audits and there is no insurance in the produce business … so you eat that," Auza said.

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Muller told Fox News that Yuma's agricultural production is vital to feed Americans. He pleaded for the Biden administration to close the border wall gaps and enforce stricter immigration policies to ease the strain on Border Patrol.

CBP announced on Jan. 6 that construction to close Yuma's border wall gaps would begin this week but it hadn't started as of Sunday evening. 

"This is produce that we're growing for the whole country, and it should be protected," Muller said. 

To hear more from Arizona border farmers on food safety concerns, click here