An anonymous reader shares an NPR report: More than 90 percent of California's crop workers were born in Mexico. But in recent years, fewer have migrated to the U.S., according to the U.S. Department of Labor. Researchers point to a number of causes: tighter border controls; higher prices charged by smugglers; well-paying construction jobs and a growing middle-class in Mexico that doesn't want to pick vegetables for Americans. As a result, the average farmworker is now 45 years old, according to federal government data. Harvesting U.S. crops has been left to an aging population of farmworkers whose health has suffered from decades of hard labor. Older workers have a greater chance of getting injured and of developing chronic illnesses, which can raise the cost of workers' compensation and health insurance. 查看全文>>