On Tuesday, March 24, 1579, a Spanish magistrate arrived at the lakeshore. Acting on an order from the viceroy, he set out in a canoe for the small island community of Santa María Magdalena Michcalco, located near the great causeway dividing Lakes Xochimilco and Chalco. The short journey took him from the deeper pool at the dock facilities into a maze of narrow canals. The waterways traversed dozens of rectangular artificial gardens that rose above the lake’s shallow waters. Local, indigenous farmers cultivated these horticultural plots all year round, and if not preparing maize for one of their half dozen annual harvests, they would have been tending to their crops of chiles, squash, tomatoes, and other vegetables. Stretching into the distance with the many gardens were water willows whose root systems, partially visible from the canoe, held together the edges of the aquatic gardens.

The sixth chapter examines how Native communities and haciendas adopted livestock rearing and, in particular, cattle ranching as a new economic activity within the lakes. Responding to the rise of the urban market for meat as well as the demographic decline within Native communities, residents of the chinampa districts expanded into the waters of the lakes in new and destabilizing ways. Alongside the chinampas, many of which survived and retained their value, haciendas and Native communities now fashioned pastures from the swamps. As they pushed further into the lake, pastoralists instituted new environmental management practices and constructed new hydraulic engineering works of their own. At the same time, the colonial administration, responding to renewed fears of flooding in the capital, increasingly intervened in the southern lakes’ hydrology. These new forces for change, when combined with higher rates of rainfall because of renewed climate extremes, undermined both the ecological autonomy and the flood defenses of the Nahua communities, portending of wholesale environmental transformation if not ruination on the eve of Mexico’s Independence.