They are mostly Hispanic, mainly from Mexico and despite their back-breaking work, they're not entirely welcome, CBS News correspondent Thalia Assuras reports.
"The illegal immigration is a weapon of mass destruction," says one caller on a local radio show.
Leading the charge against the illegal immigrant influx is Canyon County Commissioner Robert Vasquez.
"It is an economic attack on the United States," Vasquez, who is of Mexican heritage, explains.
But as Vasquez likes to point out, his grandfather came to the United States legally. Vasquez says illegal workers cost the county millions and, in a legal first, he's turning to the courts to get the money back.
Asked if he thinks Canyon County taxpayers are being ripped off, Vasquez says bluntly, "Well, of course."
Canyon County is suing agricultural companies under federal racketeering statutes normally associated with bringing down the mafia, not migrants.
"I am angry. My country's being invaded and my government is not taking any action," Vasquez says.
The claim: the companies have conspired to hire illegal workers, who drive up the county's medical and law enforcement costs.
"They're bringing in crime and they're also bringing in the gang culture," Vasquez says.
The local jail is overcrowded with a large number of immigration cases.
Noting that some inmates must sleep on the floor, Assuras asks Capt. Robert Munsey of the Canyon County jail if these conditions would persist without the illegal immigration problem.
"There might be a few, but not as many," Munsey says. "It's a problem."
There are up to 35,000 illegal immigrants in Idaho providing cheap labor. They make up a critical portion of the agricultural workforce and without them, some say, the industry could collapse.
"The people I hire in the agricultural industry are not taking jobs away from other people," Canyon County farmer Sid Freeman says.
Freeman's family has farmed here for decades. If the lawsuit succeeds he's worried the big companies won't buy his crops.
"I may be the last farmer in nine generations in America," Freeman fears.
Vasquez hopes to take his crusade to the national stage by running for Congress. That has a lot people around here worried.
"He is kind of the engine for driving divisiveness in our community and hate," says Corrine Tafoya-Fisher of Action Against Hate, a bipartisan political action committee.
But Vasquez says he's a patriot: "I'm not opposed to immigration. I'm opposed to the invasion of illegal aliens," he says.