At its annual convention Tuesday, the American Farm Bureau Federation, a lobbying group, said that states that want to take illegal immigration into their own hands should also make sure farmers have enough seasonal workers.
And if Congress doesn't overhaul immigration, farmers will assist the federal government in helping states create programs that give growers access to enough legal labor, under a policy that won preliminary approval at the annual convention.
The policy retains the Farm Bureau's long-held view that immigration policy should be set by the federal government.
"So far, all of these state programs have been on enforcement only," said David Winkles, president of the South Carolina Farm Bureau, whose members proposed the policy. "They don't address the fact that we don't have an adequate labor supply in agriculture."
Delegates were expected to take a final vote on the policy later Tuesday.
In recent years, some state governments have passed laws attempting to crack down on illegal immigrants. A new wave of legislation is expected this year as politicians consider measures similar to a law passed in Arizona. Among other steps, the Arizona statute requires that police question the immigration status of people they have reason to suspect are in the country illegally.
President Barack Obama's administration has challenged that law in court, and a judge temporarily blocked the enforcement of several of its provisions.
Farmers rely on seasonal laborers, including many illegal immigrants, to harvest labor-intensive crops such as strawberries, onions, peaches and tobacco. The agriculture lobbying group says Americans refuse to take the difficult, low-paying jobs.
The federal government has a guest-worker program for agriculture workers, but farmers say it's expensive to use and inflexible.
"If a state can venture into the arenas of enforcing immigration, then they can venture in the arena of granting temporary legal status," Winkles said.
The debate over immigration policy reflected the delegates' regional concerns. They also voiced support for a secure border. Texas representatives modified the immigration proposal so it supported the right of state governments to help enforce immigration law and border security.
Raymond Meyer, a state director who represents ranchers and farmers south of San Antonio, said drug runners in his border region will drive heavy duty trucks through rural land when they are forced off highways. That puts ranchers and farmworkers at risk, he said.
Meyer said he prefers that Congress set immigration and border policy, but added that his farmers have immediate security needs.
"We have, naturally, Border Patrol, but it's more than they can handle," he said.
Based on reporting by The Associated Press.