Precise figures are hard to come by, but according to Erik Nicholson, national vice-president for the United Farm Workers' union, as many as 70% of American agricultural workers may be undocumented.

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This allows us to charge a very reasonable amount that is affordable to farm workers and many uninsured patients we care for.

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Most of the Western Cape's 3, 000 farm workers are not employed on a permanent basis - despite working on the farms for many years.

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