The Bracero program, which lasted from 1951 through until 1965 (Public Law 78), was the last large-scale low-skilled guest worker program in the United States. (The program grew out of an earlier seasonal migrant program initiated in 1942.) The program has been well researched, including worker exploitation and conflicts between workers and employers.
Its elimination led some economists to see what happened to employment, wages and production. Donald Wise did his doctoral work in economics on the agricultural industry in California. He looked at winter melons and strawberries, two crops that required a lot of stooping and at least at that time, did not have a readily available technology to take over from humans. He estimated that production was cut back, wages increased, and more native born workers were employed. Specifically, he estimated that for winter melons, acreage used declined by 26%, production declined by 23%, wages increased by 67%, and there was a 2.5 times increase in domestic employment while total employment declined by 22%. Prices rose by 6%.
J.D. Mason looked at the impact of the termination of the Bracero program on seasonal agricultural work in Michigan for the pickle industry. He found that after a drop in acreage in 1965 and 1966 the increased use of the mechanical pickle harvester increased acreage for cucumbers for pickle production in 1967.
This posting relates how a large increase in labor costs translates into a much smaller increase in prices.
Sources: Wise, the effect of the bracero on agricultural production in California (1970?). Mason, The aftermath of the Bracero: a study of the economic input of the agricultural hired labour market of Michigan from the termination of Public Law 78 (1970).