Reading Practice 5

[1] At the beginning of the 13th century, a tribe of hunting and gathering nomads arrived in Mesoamerica, which is the south-central area of what we now call Mexico. These people were called the Aztecs. It is said that, upon their arrival at Lake Texcoco, they saw an eagle perched on a cactus and accepted it as a sign to settle there. 300 years later, this group of people had managed to establish a mighty empire, ruling over a population in the millions, from their architecturally wondrous capital city of Tenochtitlan. What made this possible was, in part, the Aztecs ingenuity in agriculture. While they didn’t enjoy the benefits of the wheel or the beast of burden, they still managed to use the land around the lakes of central Mexico to support their population through several methods.

 

[2] The first, and simplest form of agriculture is known as rainfall cultivation. This method involves cultivating only some of the land reserved for agriculture. The uncultivated land was left to fallow, which means the farming plots were left empty to collect rainfall, which helped to revitalize the soil for future crops. This prevented soil from being depleted of nutrients through overfarming. This process was abandoned as the population of the empire grew and required larger crops.

 

[3] In the hilly areas unsuitable for farming by traditional methods, particularly in the highlands, the Aztecs used terrace agriculture. Several stone walls were painstakingly built along the contours of the hillside, one above the other. The earth in each level created by these walls was filled in and flattened, creating a stepped, or terraced, arrangement of land. In this way, a sloped area was transformed into flat steps of land suitable for agriculture. Different types of terraces were used in different circumstances. On steeper slopes, they used hillslope contour terraces, with stone walls, as previously described. On gentler slopes, they created semi-terraces. These were built with less sturdy walls made of Maguey plants instead of stones. Finally, in the least steep areas, they used cross-channel terraces.

 

[4] The third method of agriculture used by the Aztecs, primarily in the empire’s valley regions, was irrigation farming. This was accomplished by using dams and channels to divert water from natural springs to the fields. What this meant was that crops depended less on rainfall, and thus the Aztecs had greater control over their own agricultural success. Even in dry years, they were able to harvest food for their population. In fact, the Aztecs didn’t invent irrigation farming, but further developed the systems that were already in place. Their achievements in this area involved taking irrigation farming to a whole new level, creating an intricate network of canals, and even redirecting part of the Cuauhtitlan River to bring water to some of their larger plots of agricultural land.

 

[5] Not all of the Aztecs’ agricultural lands were in regions that required careful management of water; some were in the swampy lands around lakes that were too wet for traditional agriculture. In these regions, they created what they are most famous for, agriculturally speaking: the “chinampas.” Chinampas were fashioned by laying down alternating layers of mud and plant matter on the bottom of the swamp or lake. Enough layers were laid down to create raised beds rising about a meter above the surface of the water. These raised beds – the chinampas – were between 2 and 4 meters wide and up to 40 meters long. The chinampas were built in rows, separated by narrow channels of water, and to tend their crops the Aztecs would move along these channels in canoes. Built within the water, and partly from organic matter, the chinampas were incredibly fertile. They yielded, on average, seven crops each year, which provided an amazing amount of food per hectare. In fact, the Aztecs managed to grow a surplus of food which they were able to sell to others.