Labor demand for export crops was driven both by territorial expansion and by the steadily rising yields from productivity-enhancing inputs. Whereas cattle ranching had low labor requirements, the new plantations were extremely labor-intensive, particularly during peak times of the production cycle, Again, cotton best illustrates the exponential growth of seasonal wage employment in Central America. Until the mid-1950s, cotton cultivation in the region required less than 100,000 pickers come harvest. Ten years later, the number of cotton-harvesting jobs surpassed 350,000. A decade after that, cotton plantations employed nearly half a million pickers.35 In addition, limited processing segments such as ginning, baling, sugar refining, and meatpacking created tens of thousands of permanent jobs. Many of these, along with employment in the modest manufacturing in wage goods tied to market agriculture, were taken by the growing numbers of displaced peasants forced to migrate to capital cities and other towns. The most precarious of those in the sprouting slums also supplied large portions of the seasonal labor. In Nicaragua, for instance, a third of cotton pickers came from large urban areas. Most harvesting, however, was done by the growing rural population languishing on the peasant margins.

Throughout the region, the very communities that were squeezed by export farming and ranching sent hundreds of thousands of men, women, and children to earn cash at harvest time. The more modern agriculture encroached on their lands, the more rural communities relied on seasonal wage labor. Unable to survive on the diminishing returns of subsistence farming, seasonal wages became indispensable. Not only did these communities supply major shares of harvesters on coastal plantations, but the proportion of their populations making the yearly trips down to the coast also grew. In El Salvador, up to 70 percent of beleaguered peasant communities in the north migrated annually in search of wages. In Guatemala, whereas between 10 and 15 percent of cotton-harvest workers were from the capital during the 1960s, far more descended yearly from peripheral highland provinces: by the end of the decade, over three-fifths of seasonal migrants came from two western highland Mayan provinces, and most of the working population from Kiché and Huehuetenango were harvesters.36