Factbox: U.S. visa types for immigrants: Papers in farmland

CHICAGO (Reuters) - There are some 185 different types of visas offered by the U.S. State Department. The government approved 7.5 million visas in 2011, with 94 percent for those who enter the U.S. on a temporary basis for travel or short-term work. The remaining 6 percent were awarded to immigrants seeking permanent residency.

Immigration experts estimate that at least 12 million immigrants remain undocumented and thus illegal in the United States, including thousands of workers in agriculture and food-related industries.

The primary document for all foreign and U.S. workers is the I-9 employment eligibility verification form, which includes original documentation that workers are eligible to work in the United States.

The program began on November 1, 1986, under the Immigration and Reform Control Act. Immigration Customs and Enforcement (ICE) has beefed up its monitoring of I-9 forms in recent years - 2,496 audits in 2011 versus 254 in 2007 - to deter employers from hiring illegal immigrants.

H2 TEMPORARY WORK VISAS

The U.S. awards temporary-work H2 visas, which are approved by the U.S. Department of Labor, for stays of up to a year, though they can renewed for up to three years. Farm workers use H-2A visas, while meat plant workers at times have used H-2B visas. There is no annual cap on H-2A visas, but there is an annual cap of 66,000 visas for H-2B workers.

U.S. agribusiness Cargill has applied for H2-B visas twice in the past 10 years: In 2007, 62 visas were approved for its Beardstown, Illinois pork plant, and in 2008 45 were granted for the company's meat division headquartered in Wichita, Kansas, according to the U.S. Labor Department.

DIVERSITY VISAS

The U.S. diversity immigrant program allows up to 55,000 diversity visas annually from a random number of countries with low immigration to the U.S. Eligible participants in the program, which was started by the U.S. State Department in 1995, are chosen in a lottery.

Some 51,000 immigrants came to the U.S. in 2010 under the diversity visas, almost 25,000 of them from African countries. If a country has sent more than 50,000 immigrants to the United States in the previous five years, it cannot participate. Immigrants from Bangladesh, Brazil, Canada, China, Colombia, Dominican Republic, Ecuador, El Salvador, Guatemala, Haiti, India, Jamaica, Mexico, Pakistan, Peru, Philippines, South Korea, the UK and Vietnam are not allowed to apply this year.

REFUGEES & ASYLEES

The United States admits tens of thousands into the country each year under refugee or asylum status granted to those who have been persecuted or fear they will be persecuted on account of race, religion, nationality, political opinion and/or membership in a particular social group. Refugee status is given to those living outside the U.S. and their immediate relatives, while asylee status is awarded to those already in the U.S. and their immediate relatives.

In 2011, 56,384 refugees (25,075 principal applicants, 31,309 dependents) were admitted. The leading countries were Burma, Bhutan, Iraq, Somalia, Cuba, Eritrea, Iran, and Congo. There were almost 25,000 U.S. asylees last year, with 34 percent from China.

AMNESTY

Millions of illegal immigrants have been granted amnesty through different amnesty laws in the past two decades, with the largest number in 1986, under the Reagan administration, when 2.8 million illegal immigrants were granted amnesty under the Immigration and Reform Control Act. Undocumented immigrants received a Green Card - the first step in becoming a permanent resident and eventually a U.S. citizen.

Additionally, their immediate relatives or dependents, which included roughly 143,000 individuals, also qualified for amnesty. This was the first time the U.S. granted amnesty to a group of illegal immigrants; in the past it was awarded only on a case-by-case basis.

On June 15, President Barack Obama announced that the United States would stop deporting illegal immigrants 30 and under who entered the country as children if they meet certain requirements. Up to 1.4 million children and young adults could benefit from Obama's policy change.

Sources: U.S. Department of Labor, U.S. Department of State, Department of Homeland Security, U.S. Immigration and Customs Enforcement, U.S. Citizenship and Immigration Services, Pew Research Center, interviews with immigration experts.

(Edited by Prudence Crowther and Douglas Royalty)

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