The authors spoke only with those Mixtecs who had some Spanish or English language capability, thus missing those made particularly vulnerable to exploitation due to a language barrier. Also, workers experiencing the worst conditions were most likely to be inaccessible to the interviewers. Mixtecs are subject to high labor standards violations, with over one-quarter of those interviewed reporting nonpayment of wages on at least one occasion. Mixtecs are concentrated in jobs in which payments for obligatory services such as rides to work are a condition of employment. Mixtecs are concentrated in jobs with short duration, and are more migratory compared to other Mexican farmworkers.
Mixtec migrants constitute a large pool of new labor which can be hired for lower wages.
The hiring of these laborers has the effect of undercutting gains in wages and working conditions made possible for mestizo Mexican farmworkers during the 1970s. As evidence, the authors cite the ten percent decline in real wages for California farmworkers over the past decade. The authors also provide a detailed case study of how ethnic replacement has impacted the farm labor market for the raisin grape harvest in the San Joaquin Valley. Significant acreage increases in fruit, vegetable and horticultural crops have increased labor demand by some 20 percent over the past 15 years. At the same time, economic crisis in Mexico and the 1986 immigration reform law have dramatically increased the supply of labor Rather than a labor shortage once feared by growers, a tremendous oversupply of farm labor exists.