Farmers from California to New York are struggling to find enough people to harvest their crops this season, a shortage they blame on state and federal laws designed to crack down on the migrant labor that makes up the bulk of the nation’s seasonal farm workers.

“We see shortages in all parts of the country,” said Kristi Boswell, director of congressional relations for the American Farm Bureau. “Farmers are struggling with fewer bodies out there to harvest the crop. They’re definitely stressed.”Farmers with labor-intensive crops or livestock, including fruit, vegetables, nuts, Christmas trees and dairy cows say they are being hit especially hard.

“We’ve got neighbors literally competing against each other just to have enough of a work force to harvest their crops,” Boswell said.

Among those affected:

— Ralph Broetje, president of Broetje Orchards, a family owned apple farm in Prescott, Wash., said he was about 500 workers short of the 1,000 he needs to pick the fall harvest.

— Maureen Torrey, vice president of marketing for Torrey Farms, Inc., a family-owned dairy farm in upstate New York, said the family runs “help wanted” ads in the local newspaper every day but still can’t find enough workers.

— Nan Walden, vice president of the Green Valley Pecan Co. in the Santa Cruz Valley south of Tucson, Ariz., said the family farm needs to hire about 50 to 60 workers during the fall and winter harvest season but is finding it increasingly difficult because of the chilling effect of the state’s tough anti-immigration law.

Strict immigration policies in states such as Arizona, Alabama and Georgia have scared away skilled migrant workers and a federal visa program for agriculture workers has failed to meet farmers’ needs, said Craig Regelbrugge, co-chairman of the Agriculture Coalition for Immigration Reform. The coalition represents about 300 farm groups whose members produce fruit, vegetables, dairy products, nursery and greenhouse crops, poultry, livestock and Christmas trees.

Agriculture has one of the highest shares of foreign-born and illegal immigrant workers among U.S. industries, according to a February 2012 report by Philip Martin, an agricultural economist at the University of California, Davis. More than three-fourths of the roughly 2.4 million farm workers are immigrants, usually born in Mexico. More than half of farm workers are illegal immigrants, the report says.

“Upwards of 70 percent of the hardworking people who are feeding us frankly aren’t from around here, and their papers (work documents) aren’t so good,” Regelbrugge said. “We lack a legally authorized work force.”

“Wake up America,” said Larry Wooten, president of the North Carolina Farm Bureau. “We don’t get our blueberries picked without these people. We’re doing all that we can to put the pressure on Congress in hopes that we can arrive at a workable solution.”

But critics say such a plan would provide cheap labor for farmers at the expense of U.S. taxpayers, who would pick up the tab for educating the workers’ children and paying their health care costs.

“If we ask farmers to pay for education and health care, they’d mostly say, ‘No, we’d like taxpayers to do that,’ ” said Steven Camarota, research director of the Center for Immigration Studies, which advocates reduced immigration. “It creates a large-scale social cost.”

Camarota said farmers should be able to find legally authorized workers through an existing federal program that allows foreign citizens to obtain visas for seasonal farm work in the United States. But the program, known as the H-2A visa program, is widely criticized by farmers as unworkable.

Dairy, hog, and poultry farmers complain that it doesn’t help them because they need workers year-round and the visas are designed for seasonal harvest work that lasts less than a year.

Crop farmers say the program is too bureaucratic and doesn’t deliver workers quickly enough when farmers need them most. It also imposes what many farmers see as unfair requirements — such as constructing housing for seasonal workers that may only be needed for a few weeks to pick strawberries or other produce.

“It’s a very complicated and burdensome system,” said Boswell, with the Farm Bureau.

Most farmers end up hiring workers without going through the program. That means possibly hiring illegal immigrants with false documents and facing federal sanctions. The Obama administration has stepped up its audits of employers to check compliance with federal immigration laws. Farmers can be fined and forced to fire their farm workers if the workers’ documents cannot be verified.

From January 2009 through April of this year, the Obama administration had audited more than 7,500 employers — including farmers — suspected of hiring illegal labor and imposed about $100 million in fines, according to Immigration and Customs Enforcement.

“Our farmers want to hire legal people, but when you don’t have the labor and the crops need to get in and able bodies walk up to your farm, you do what you can to save your crops and your livelihood,” said Wooten, a retired tobacco farmer.

But Camarota, of the Center for Immigration Studies, said he believes farmers are exaggerating shortages. The federal government does not keep statistics on the number of seasonal farm workers employed in the United States each year.

“You may have a week or two when the last raisins are on the vine and you’re scrambling to find someone to pick them,” he said. “But if there was a widespread shortage of farm labor in this country, then farm wages should have gone up fast with desperate farmers competing for workers. And that hasn’t happened. In the past five years, wages have only gone up 1 percent.”

Regelbrugge said farmers began to see real shortages in 2006-07 in certain places, such as in Northern California’s pear crop. Since then, it has been happening with more frequency in more places, he said.

“We don’t cry shortage very often,” he said. “It’s happening right now.”

Walden said some of the tough rhetoric around immigration enforcement is scaring off legal workers, not just those who are undocumented.

She believes Arizona’s controversial immigration law — known as SB 1070 — has led to racial profiling that makes Hispanics feel unwelcome. She said the pecan farm’s plant manager — a U.S. citizen with a degree in biochemistry — has been stopped by U.S. border patrol agents and told she was acting suspiciously because she was driving so carefully.

“It creates an inhospitable climate that understandably scares people of Mexican descent,” Walden said. As a result, she said, some skilled farm workers may opt to go to California or another state that is viewed as friendlier to them than Arizona.

As they appeal to Congress for help, farmers say they are trying to overcome the misconception that farm workers are unskilled laborers. Many of them have developed special skills over the years and are relied on by farmers for their expertise in picking crops quickly or operating heavy farm machinery.

“Enforcement-only immigration policy has just devastated the skilled labor force we have depended on for the past 20 years,” said Broetje, the Washington state apple grower. “It’s getting worse every year, and it’s going to end up putting some growers out of business if Congress doesn’t step up.”