Grossman cited reports from his organization as well as media reports that in the Bay Area’s single biggest farming area, the Salinas Valley, occupying parts of Monterey, Santa Cruz and San Benito counties, "almost no crews were out today."

This region employs approximately 60,000 workers harvesting strawberries, lettuce and other fruits and vegetables, but today, Grossman said, "the fresh fruit and vegetable industry on the Central Coast was virtually shut down."

Grossman added that wine country farm workers harvesting grapes in Napa and Sonoma counties were also absent from work today in large numbers.

"These job actions are really historically unprecedented," he said. "I think it sends a powerful message about the depth of farm workers’ sentiment for genuine immigration reform."

However, the one-day work stoppage shouldn’t have a permanent economic impact and a raise in prices is not expected, Grossman said.

Some companies had even announced that workers could take the day off, and some made previous arrangements with the workers to have them log more hours over the weekend in order to make up for time lost from Monday’s action.