@hingehead,
It's the same here in California. Our farms are always short-handed during harvest, and many Mexicans cross the border to work on our farms. Many complain that jobs are being stolen by migrants, however, we don't see many whites working out on our farms doing the hard labor for minimum wage.
http://articles.extension.org/pages/9960/migrant-farm-workers:-our-nations-invisible-population
When we were children, all my siblings and I worked on the farms during the summer months to harvest the fruits in the Sacramento Valley. At least fruit trees provided some shade, but harvesting tomatoes and hops was in the open field. Many people do not have that experience, and don't appreciate the hard work for minimum wage that it provides.