Thursday's immigration deal reached by a bipartisan group of senators and the White House includes a pilot program for legalizing agricultural workers who farmers say are in such short supply that tons of fruits and vegetables have been left unplanted or unpicked.

Sen. Dianne Feinstein, D-Calif. said the aim of the bill is "to see that we have a consistent labor force for agriculture, the one industry in America that almost solely depends on an undocumented work force.

"I believe that we have achieved that in this bill," Feinstein said at a press conference.

Farmers say that as immigration enforcement has tightened in recent years, worker shortages have ranged from 10 percent to 30 percent across the labor-intensive produce industry and have affected dairy farms and nurseries, too.

In some cases pears, strawberries and other crops have gone unharvested. In others, farmers have chosen not to plant, or have reduced plantings of the most labor-intensive crops, such as asparagus. Economic losses have been estimated in the millions.

"We're looking at deterioration of the work force and the inability of people to survive. We're looking at the failure of farms and small businesses," said Craig Regelbrugge, co-chairman of the Agriculture Coalition for Immigration Reform.

The "AgJobs" program pushed by Feinstein and Sen. Larry Craig, R-Idaho, would create a five-year pilot program to legalize immigration status for those who have worked in U.S. agriculture for at least 150 days over the previous two years. The program would be capped at 1.5 million.

Feinstein spokesman Scott Gerber said the basic framework of that bill was becoming part of the deal Thursday.

Their measure would be a separate program and subject to different requirements than for other guest workers or illegal immigrants already in the country, Gerber said.

The proposal passed the Senate last year as part of a larger immigration bill, but the House and Senate failed to reached a compromise on the legislation.

Currently the farm labor force in the United States numbers about 1.6 million, according to people in the industry, and 70 percent or more are estimated to be illegal.

An existing program for temporary farmworkers — the H-2A visa — allows workers into the U.S. for 10 months at a time. About 40,000 workers per year come in under that program, but growers complain that it is extremely onerous and bureaucratic