There is a Western European environmental imaginary that assumes arid environments are incapable of supporting human life, or that the quality of that life, if it exists, is hardly worth living. From this perspective, it is easy to see agriculture and arid environments as antithetical. Irrigation becomes necessary in arid environments like the Mezquital Valley when the plants you want to eat did not evolve to survive aridity, but there are plants that have evolved in this way, and many of them form the basis of rich culinary traditions in central Mexico. We began researching the arid foodways of one such culinary community in central Mexico, known as the Otomí or ñähñu, in the Mezquital Valley of Hidalgo, Mexico (Map above: Etnografía del Otomí. Jesus Salinas Pedraza. Mexico: Instituto Nacional Indigenista, 1984). Exploring Otomí Indigenous foodways in the Mezquital Valley became a way of questioning the culinary imagination of irrigated agriculture, but it also led us to reflect on deeper biases as well, as we struggled to visually represent the alternative forms of environmental knowledge we encountered in Otomí dryland agriculture.

Today, we find ourselves working in the twilight of natural history, where the normal visual conventions for communicating objects and processes at the blurry boundary between biology and geology tend to fail to convey the kinds of continuity our research suggests is fundamental to these agricultural systems. The traditional disciplinary distinction between plant knowledge and soil knowledge in our academic institutions is something that the entire history of Mesoamerican agriculture suggests is a waste of time. For this reason, our drawings of the soil-plant-animal world of dryland agriculture in the Mezquital Valley embraces a precarious balance between objects and processes that we hope has pragmatic value as a faithful reflection of its key material relationships.

The drawings we developed are an attempt to represent the set of relationships that soil forms within rather than a set of morphological traits it has at the moment it’s measured. To do this, we began with an interest in identifying human and nonhuman agencies that affect soil formation in the Mezquital Valley. Our use of the term “agency” is meant to invoke Karen Barad’s feminist materialist reading of the term in Meeting the Universe Halfway: Quantum Physics and the Entanglement of Matter and Meaning (2006), where agency is something that is produced through material relationships rather than through individual acts of willing. This is a particularly helpful way of thinking about agency in soil, as nothing ever happens in soil that doesn’t clearly depend on something else. Instead of thinking about agency as the authorship that we ascribe to independent actions, soil challenges us to think about agency as something that is always dependent on some other agency for its capacity to act. In other words, there are no heroes in the soil. Everything depends on something else. Instead of drawing the soil as a collection of objects like sand, silt, and clay, we have tried to produce a portrait of the relational network in which these objects become agential in the soil. In this way, our soil profile is intended to reveal the human and nonhuman relationships that the soil of the Mezquital Valley both forms and forms within.

The domestication of corn (maize) involved only five genes, but remained a complete botanical mystery for most of the twentieth century. Unlike the obvious wild progenitors of rice, barley, and wheat, corn seemed to appear out of nowhere, having no clear ancestors. The discovery that teosinte was this missing ancestor was surprising, as it bears almost no resemblance to corn. A dryland grass, teosinte’s fruit has a hard unyielding coating that is inedible, although the stalk of the plant may have been chewed for its mild sweet taste. Transforming teosinte into maize is among the most startling and sophisticated accomplishments in the history of agriculture, effectively turning the fruiting body of teosinte inside-out. The subsequent transformation of this miraculous crop into the essential scaffold for the “three-sisters” of Mesoamerican agriculture was an innovation that made its cultivation sustainable, producing soil fertility rather than diminishing it. Today, we subsidize the high nitrogen requirements of maize with industrial fertilizer, enacting a further and even more unlikely transformation of a perfect food into a petroleum product.

Mesoamerica is the only part of the world to have invented agriculture without the mechanical power, manure, and nutritional protein of large herbivores. Without the ability to plow fields and fertilize them with manure, agricultural fields needed to be multispecies systems that produce soil fertility through geomorphology and plant-soil relationships. A key theme that emerges in Mesoamerican agriculture is precisely this insight, that multispecies agriculture can create soil fertility through the very things that we now associate with the depletion of soil, such as planting and harvesting. In the Milpa system, beans, corn, and squash are planted together. Beans have the ability to fix nitrogen in the soil, but are climbing plants that need a vertical structure to find sunlight. Planting beans under nitrogen-hungry corn gives them a structure to climb and makes more soil resources available for both plants. Squash is then planted around the corn, so the broad leaves of the squash plant protect the soil from direct sun exposure, conserving soil moisture. The fruit of these three plants, called the “three sisters” of Mesoamerican agriculture, then form a perfect protein when consumed together, further eliminating the need for large herbivores as a source of nutrition. The combination of these plants produces the soil fertility that the plants need to survive, as well as the energy that humans need to plant them.

Two rabbit species live in the region of Hidalgo: the black-tailed jackrabbit and the cottontail. The two species share similar characteristics involving diet, reproduction, predators, and habits. The drawing portrays the life cycle of a rabbit and its direct influence on the dispersal of the Opuntia (Nopal) seeds. The rabbit’s diet consists of the prickly pear (Higo chumbo) and desert vegetation such as grass. The fruit of the cacti is favored, but the pads are also eaten during times of prolonged drought. The rabbit expels two types of excrement: cecal and fecal. After the food is digested, the rabbit consumes its own cecal to finally be expelled as fecal. The fecal contains Opuntia seeds, which take approximately 4.4 years to germinate. The rabbit’s digestive habit, named coprophagy, is hypothesized to be the driver for the rapid spread of the Opuntia cacti in the region.

The Nopal cactus is a staple food of the dryland diet for both people and rabbits, but for the Spanish Empire it also produced the most valuable New World export after silver and gold. The Nopal is parasitized by a scale insect called Cochineal (Dactylopius coccus), which produces a vibrant red dye when crushed. Cochineal provided the red color of the British “Redcoats” and Vatican cardinals, it was used by Renaissance painters like Rembrandt and Raphael, and until 2009 it was the red dye used to color Skittles candy. The cultivation of Nopal for Cochineal production is difficult and labor-intensive. It cannot be automated, and took the Spanish Empire a few hundred years to understand. Today it takes around 70,000 insects to produce a single pound of the dye.

Escamoles are the eggs of the velvety tree ant. The nests from which escamoles are harvested are located beneath the Maguey plant. The ants maintain a symbiotic relationship with their host plant, providing antiherbivore and bacterial removal services in exchange for the use of the plant as a source of food and, more importantly, water. The nest itself is composed of clay and sand, with a spongelike formation that reduces compaction and introduces organic matter into the soil profile.

Oxalis sp. are commonly eaten on tacos in dryland environments in Central Mexico. Its rhizome has an intensely acidic taste, and is still used medicinally in many parts of Latin America. It appears in the oldest extant Latin American herbal, the Codex de la Cruz-Badiano, which depicts the plant as a treatment for dry mouth. This acidic taste comes from oxalic acid, which is produced by the plant to discourage herbivory. Oxalic acid also functions as a good chelating agent for zinc, cadmium, and lead, making it an excellent soil remediator in the aftermath of industrial contamination.

Like Oxalis, Datura stramonium appears in the Codex de la Cruz-Badiano (1552) as a medicinal plant defined by its relationship to the ant species Forelius pruinosus, which forms large polygynous underground nests in disturbed dryland soil. Birds disperse its seeds without being affected by its strong hallucinogenic compounds, and a night moth pollinates its large white flowers when illuminated by the right amount of moonlight. Rather than simply seeing Datura as a plant in an arid environment, its very biology seems to invite us to inhabit its hallucinogenic intersection between flower, moon, bird, moth, ant, soil, and the inebriated human plant propagator who sent it to unsuspecting Europeans in the hope of discovering a new sixteenth-century pharmacological commodity.

Urera caracasana is called Atzitzicaztli in Nahuatl, and it is a fortress of plant defenses. Atzitzicaztli produces small pearl-like food bodies that appear on the underside of leaves and around stem offshoot areas, which are rich in lipids, proteins, and carbohydrates. These food bodies attract aggressive ant species, which protect it from larval herbivory. As a stinging nettle, the plant also produces spines containing histamine, anticipating the effect of this toxin on mammalian bodies that might also be interested in grazing its foliage. Within this fortress the nettle offers bright red berries that are toxic to everything but the birds that disperse it. In Atzitzicaztli, we can see our own reflection, as the vague outline of what it rejects and has no use for.