The failure of existing guest temporary visa programs can be summarized in these figures: the number of workers under them in Florida is probably equivalent to 1% of all undocumented workers in that state.
These programs are designed to attach each worker to a particular employer for a specified period of time – in months. The Palm Beach Post ran on Dec. 9, 2003, as part of an extensive series on farm labor, an analysis of how the federal governments guest worker provisions for temporary farm labor have worked in Florida. Farm employers rarely use these programs. According to the federal government only 2,423 H2A and H2B visas were issued to Mexican for work in Florida. I have previously estimated, drawing on Urban Institute figures, that as of 1/1/06 there were roughly 600,000 undocumented workers in Florida. Assume that total figure in 2002 was 450,000: H2 visa programs were equivalent to less than 1% of Florida’ undocumented workers.
According to the Post:
According to Tom Canahuate, a diplomat at the U.S. consulate in Monterrey, 66,379 such visas were issued in Mexico in the last fiscal year  ending: 24,946 H2A visas for agricultural workers and 41,433 H2B visas for other jobs. Only 2,423 of the total number were for work in Florida.
The program requires employers to pay workers’ travel expenses into and out of the U.S. and to pay a wage commensurate with that of Americans working in the industry. Employers also must provide free housing for employees.
“Employers have always insisted that H2A is too much of a hassle, makes too many demands on them,” says attorney Greg Schell of the Migrant Farmworker Justice Project.
“There have been awful abuses of H2A workers over the years,” says Schell. The visas allow a migrant to work only for the employer who sponsors the visa. If the worker is abused in any way, he can quit, but must leave the country. Many put up with abuse, including cheating on wages, rather than report their bosses.