Subsistence and Commercial Activitíes. Since pre-Hispanic times, Mam have been primarily subsistence farmers, cultivating the typical Mesoamerican crops of maize, beans, and squashes. Until the 1960s, Mam cleared fields with machete and hoe, planted them for several years, then fallowed them to work other plots. Yields ranged from 570 to 1,000 kilograms of shelled maize per acre. Land was under nearly continuous cultivation in richer valley bottoms, but less promising terrain required five to ten years or more of fallow for at most two years of use. Since the 1960s, chemical fertilizers have extended periods of use and raised yields, but population growth offsets any real gains. Most clearing, planting, and weeding is done between April and August; harvests are between November and January, depending on the elevation. To generate needed income, Mam with suitable lands now also cash-crop in coffee on a small scale. Those without coffee land or enough maize land to feed themselves must migrate seasonally to lowland plantations, where coffee and cotton harvests fall mostly between July and January.
Industrial Arts. During slack periods in the agricultural cycle, many Mam traditionally engaged in artisanal production of cloth, pottery, furniture, and basic necessities such as salt, lime, and stone metates for grinding maize. Almost all Mam women still weave on traditional backstrap looms. Using commercially manufactured thread, they make their own blouses, skirts, belts, and whatever handwoven articles of clothing men in their towns still wear.
Trade. During the late nineteenth century, Guatemala's coffee economy stimulated the growth of rural marketplaces to supply Ladino towns and plantations. Mam traders still work these markets today, peddling local goods from different Mam communities and the few consumer goods that rural Mam need and can afford—coffee, salt, lime, unrefined sugar, soap, kerosene, thread for weaving, clothing, tools, and pots for cooking and for fetching, storing, and heating water; occasional luxuries include cigarettes, sweets, jewelry, radios or tape recorders, and sugarcane rum. Better roads and transportation have eased Mam access to major market centers, but the inflow of cheap imported goods has also undermined local artisanal production.
Division of Labor. Mam men work the fields, engage in trade, and construct and repair buildings; women cook, weave, wash clothes, and provide primary child care. Both men and women work for wages, and, during the harvest season, entire families migrate to the plantations, many for months at a time. Truck and bus transport and commercial weaving on foot looms are prominent among the few nonagricultural Mam professions. Younger Mam also work as schoolteachers, usually in rural posts eschewed by Ladino teachers.
Land Tenure. Until the twentieth century, most Mam municipios held land communally, granting usufruct rights to individuals for specific plots. Because use rights could be sold, sublet, or passed on to heirs, renters often came to consider these parcels private property, although they were forbidden by law actually to sell the land. As competition for land intensified and the Guatemalan government sought to sustain communal land tenure, Mam turned increasingly to individual legal titles to secure access to land. By the 1950s, private landholding predominated in most Mam communities.