Let's look at the big picture.
Summary
"The hand harvesting of fruit and vegetable crops in the United States is a labor-intensive operation that accounts for about 50 percent of total production costs. The number of crops and percentage of crop acreage that are mechanically harvested today have increased somewhat since the late 1970s. Most of these crops are used for processing.
However, at least 20 to 25 percent of the U.S. vegetable acreage and 40 to 45 percent of the U.S. fruit acreage is totally dependent on hand harvesting. The crops represent about 30 percent of the U.S. fruit, nut, and vegetable acreage and have an annual farm-gate value of over $13 billion. Declining labor availability and increasing labor costs are reducing U.S. growers competitiveness with foreign suppliers. Harvest mechanization and improved production technologies show promise for keeping U.S. growers in business."
In arguing for expanded agricultural guestworker programs, lobbyists for farmers often claim that fruit and vegetable production in the United States would be impossible without large and continuing infusions of foreign labor.
cis.org