Deserts rarely get their due. During my dissertation-proposal defense a faculty member turned to me with a puzzled look and asked, "But aren't cattle grazers? What are they eating if there's no grass?" In Sonora, where browsers graze and grazers browse, general rules of animal diet tend to fall apart. Given a choice between eating rocks or mesquite pods, cattle favor mesquite. For the most part, cattle adapt quickly and learn to browse shrubs eight months out of the year, as they wait for the summer and mild winter rains to produce herbaceous forage.
Sonora is a place of contradictions. Cattle ranching occupies more than 90 percent of the state's land base, yet this extensive form of land use depends on the irrigated districts for supplementary feed. Cattle ranchers are therefore also agriculturists. A second contradiction is in the rhetoric of buffelgrass (Cenchrus ciliaris), a species of exotic African grass planted on rangelands, which is much decried by local and international environmentalists. Methods of preparing rangeland for seeding with buffelgrass are not pretty: One of my colleagues refers to this as "bulldozer ecology." Aesthetics notwithstanding, soil erosion may actually decrease once buffelgrass is in place - at least that is what my preliminary results indicate.
Although cattle have been present in Sonora for more than four hundred years, ranching as a more formal industry has grown in a remarkably short time. Mexican ranchers, of course, did export to the United States before the aftosa (foot-and-mouth disease) crisis of 1946-1954. The changes wrought by U.S. policies toward diseased Mexican cattle, however, were far-reaching. A sharp decline in cattle exports and numbers led to the importation of "fine" breeds of European ancestry, many times at the expense of the Mexican government, though international moneys certainly contributed. Between 1960 and 1985 the World Bank invested more than U.S.$1.5 billion in Latin American cattle projects, in an effort to "improve" animals. The consequences of such "improvement" are now well known: Improved animals need improved food. In other words, croplands across Latin America have been converted to feed cattle, not people. Small communities, such as Baviacora - where I stay [ILLUSTRATION FOR FIGURE 1 OMITTED] - have witnessed dramatic changes in land use and crop cover. Wheat crops have nearly disappeared, alfalfa and oats have surged forward, and corn is now mostly reserved for other animal industries that have appeared in the Rio Sonora region. Indeed, the pork industry of Sonora is growing at a faster rate than the cattle industry, a fact liberally evident on a drive with the windows down on any Sonoran road. In this matter, Sonora is certainly not unique: Scholars have noted this ganaderizacion (livestockization) of Mexican agriculture for decades.
Studying cattle ranching, and agriculture in general, in an arid realm has its advantages. First, patterns of land use are more readily visible, for the green pastures contrast sharply with the surrounding gray and brown. Extreme temperatures call for extreme measures. When water is lacking, ranchers and smallholders burn the spines from cacti so that cattle can eat and rehydrate at the same time. A final plus for research here is the ecological sensitivity of the place: Small environmental changes can produce dramatic results on the landscape. A gentle spring rain can delay cactus blooms. A cow tumbles down a hill and causes a rockslide; the alluvial material accumulates in a canyon and produces a series of ponded reservoirs for both wildlife and cattle. Small, beautiful things can be accidents, but this makes them no less notable when they occur. Sad events may also lead to a quick environmental impact. A rancher's daughter drowned in a stockpond, and the grief-stricken rancher destroyed the earthen dam that created the reservoir. After the retaining wall was blown up, thick, coffee-colored liquid spewed down the canyon. …