CHAZY, N.Y. — Shortly after the Sept. 11 terrorist attacks, the state labor department sent Donald Green III six Mexican migrant workers. He checked their documents and put them to work on his apple orchard.

But weeks later, amid heightened concerns over terrorism and border security, immigration officers caught the men and said they were in the country illegally.

If a bill passed by the U.S. House of Representatives becomes law, Green and farmers like him would also be lawbreakers. They would be charged with a crime and face thousands of dollars in fines.

It has Green concerned. He said the bill would make him responsible even though the workers gave him documents to work on his sprawling 850-acre orchard seven miles south of the Canadian border.

"They are putting all of the burden on the employer who does not have the resources or ability to verify these things. That would be extremely unfair," he said.

In recent weeks, thousands of immigrant rights supporters have rallied to oppose some of the proposals, expressing concern about stiff criminal penalties and calling illegal immigrants important to the economy.

Chief among the concerns of most growers is the loss of much-needed labor. They say that without migrant workers, they would face bankruptcy and the cost of food would soar.

Many say they'd be hard-pressed to find any U.S.-born workers willing to do tough manual labor. Green said he has to import 156 men from Jamaica through a guest-worker program to get his crop to market.

In Illinois, hog farmer Art Lehmann said he would like to see Congress expand the current guest worker program to allow foreign-born workers to stay longer than the 10 months currently allowed.

"I have work 365 days a year," said Lehmann, who has 4,000 sows on his farm in Strawn, Ill., 100 miles south of Chicago.

He said, "We need these people to do the work and they want to do the work."

Luis Torres, western New York Director of Rural and Migrant Ministries, a farmworker advocacy group, said most immigrants are taking the House bill with a grain of salt.

"You're talking about 11 million people, you're talking about industries shutting down," he said. "I don't think that anyone who understands the situation would think that would be implemented."

According to a U.S. Department of Labor survey conducted in 2001 and 2002, 78 percent of the nation's 1.8 million crop workers were born outside the country, mostly in Mexico. More than half, 53 percent, weren't authorized to work in the U.S. There are about 40,000 migrant workers toiling in New York each year.