While the Democratic presidential candidates and the presumptive GOP nominee debate the merits of their economic and national security plans, many of Pennsylvania's agriculture workers are frustrated by the lack of attention to an issue where the three differ very little: immigrant guest workers.

"There are no meaningful differences between the candidates on immigration," said Mark Krikorian, executive director at the Center for Immigration Studies.

With more than 58,000 farms in the Keystone State, growers who ship large portions of the nation's mushrooms, milk and grapes are trying to draw attention to the steady decline in immigrant workers they have been able to use for year-round work and seasonal harvesting.

David Rice, along with his brothers, owns and operates Rice Fruit Company in Garders, Pa., and says this year's sparse showing of seasonal guest workers will mean a lower-quality apple harvest.

"During this time of year, we would like to have 25 (workers), but we have 15," Rice said. "It means that we won't be able to prune."

Farmers across the state were brought into the spotlight earlier this month when the press picked up the story of tomato grower Keith Eckel, a partner of Fred W. Eckel Sons Farm, Inc. in Clarks Summit, Pa., who decided to cancel his entire tomato crop after he could only get about 50 workers to do a 110-person job.

"Keith Eckel explained how he has been in this business for years, and he has followed the law to a T," said Mark O'Neill, media relations director for the Pennsylvania Farm Bureau (PFB). "In his mind, every worker he hired was a legal worker. He's done everything required by law. It's the government's job to work to make sure these people are legal or not, it's not the job of the farmer."

Eckel does not work with guest workers on H-2A visas because, like many growers, he feels the rules are too complicated and cumbersome.

Rice agrees. "The H-2A is tough bureaucratically to comply with -- more than that it's been uncertain politically," he said.

As immigration reform remains stall in Congress, fewer workers without H-2A visas are crossing the border to find jobs. Of those who do, fewer and fewer make the long trek to find work in northern states.

While some growers adjust to the shortage by accepting lower-quality products and others cancel their entire crops, still others have had to rely on crops that are more easily mechanized, such as corn and milk products.

O'Neill worries labor-intensive industries will suffer if the guest worker supplies continue to drop. "If something isn't done soon, it could be a major issue," he said.

Farmers like Eckel have helped draw attention to the issue and urgency of a national and local immigrant guest worker plan. While the subject is largely bypassed by candidates on the campaign trail, some White House hopefuls have contacted the PFB since Eckel's story emerged in media outlets.

"We have been contacted by two of the three on the issue, and I guess they're looking for more information," O'Neill said. "We encourage them to do so. We think it's a very important issue."

The PFB largely supports legislation -- still being finalized -- by Sen. Dianne Feinstein, D-Calif., who seeks to make it easier for growers to bring in foreign labor for seasonal labor positions.

All three candidates have expressed interest in Feinstein's plan, tentatively referred to as the Agriculture Emergency Relief Act, according to the Watertown Daily Times. The proposal would allow workers to stay in the United States for up to five years but would not offer amnesty or a path to citizenship. The plan is a modified version of the former AgJobs plan, which offered slightly more protection to immigrant farm workers.

AgJobs is supported by Democratic presidential contender Sen. Hillary Clinton, who "has been a longtime supporter of AgJobs," Angel Urena of the Clinton campaign said in an e-mail interview. "The AgJobs compromise was reached after years of negotiations, and it represents a unique agreement between farm worker labor unions and agricultural employers."

Arizona Sen. John McCain, the presumptive Republican nominee, has made immigration reform a central tenant of his political life for several years, but his 2005 plan for a path to eventual citizenship and his recent courtship of Hispanic voters has angered some conservatives in the party's base.

McCain's "Secure America and Orderly Immigration Act," introduced along with Sen. Ted Kennedy, D-Mass., failed to pass in Congress because of divisive views about naturalization and amnesty.

The McCain-Kennedy plan also put a strong emphasis on border security. "In practice, McCain is likely to be most aggressive to opening the borders and loosening immigration," Krikorian, of the Center for Immigration Studies, said.

Sen. Barack Obama has recently worked with Kennedy -- who endorsed the Illinois senator for the party's nomination -- to help provide incentives for employers to verify the legality of their workers and make it easier for legal immigrant workers to find jobs.

O'Neill says the Pennsylvania Farm Bureau organization supports the Feinstein plan because it eliminates an option for citizenship that many are against, but still allows workers to come in for seasonal or year-round labor.

Not all farmers, however, feel that eliminating citizenship is the answer. While he supports Feinstein's plan, Rice says he "would like to see a path to naturalizing."

"We understand that it's a politically tough proposition to advocate anything that seems to be amnesty, but the undocumented labor force is used extensively in agriculture. They're enterprising people, they're in no way, from our point of view, milking the system," he said.

-- By Alexis Matsui, Online NewsHour