A History of Land Use and Natural Resources in the Middle San Pedro River Valley, Arizona

This paper reconstructs and interprets the land use and natural history of a poorly studied reach of the San Pedro River in southeastern Arizona (figure 1). The paper is organized chronologically, beginning with a summary of prehistoric conditions and human activities. Greater emphasis is placed on the historic period, however, for which human uses and impacts are better documented, more directly relevant to current conditions and issues, and generally more significant than in centuries past. Social, political, and economic topics are covered only to the extent that they bear on the use, ownership, and management of land, water, vegetation, livestock, and wildlife. Similarly, events that occurred outside of the study area are treated only insofar as they affected local conditions and activities.

Elevations in the study area range from 800 m at the north end of the river corridor to more than 2,600 m at the top of the Rincon Mountains. The San Pedro River falls roughly 230 m on its way through the area. Average annual precipitation increases with elevation from roughly 25 cm to more than 60 cm. The terrain is extremely rugged, characterized by deep tributary canyons and washes cut into the foothill slopes on either side of the river. Vegetation communities include cottonwood-willow riparian forests and mesquite bosques along the San Pedro River, mixed broadleaf forests in tributary canyons and washes, Upper Sonoran desertscrub on lower elevation uplands, Sonoran and Chihuahuan semidesert grasslands at intermediate elevations, and madrean oak woodlands in the surrounding mountains. Conifer forests occur at the very highest elevations.

Development is very limited. The three roads that serve the area are unpaved and minimally maintained. Two towns—Redington and Cascabel—appear on the map, reflecting past locations of schools, stores,

Figure 1.

Map of the Middle San Pedro River Valley, Arizona. The river flows from south to north. The area covered by this study encompasses the lands tributary to the river from the Narrows (a geological feature that separates groundwater basins above and below it) downstream to Alder Wash and Kielberg Canyon. (Source: Arizona Geographic Information Council.)

and post offices, but neither has an identifiable commercial center at present. Electrification occurred in the late 1950s and telephone service arrived in 1993. The current population, estimated at 175 year-round residents, is less than was found in the area in the early twentieth century, and probably less than occurred during some prehistoric periods.

Crop agriculture and livestock production have been the dominant land uses since the arrival of Spanish missionaries in the region 300 years ago, although these activities were limited and sporadic due to the threat of Apache depredations until the late 1870s. State lands are leased to private ranchers for grazing, as are most national forest and Bureau of Land Management (BLM) lands. A modest amount of mining occurred in the mountains early in the twentieth century. Hunting is a long-standing land use throughout the area, now limited to fall and winter seasons; other recreational uses are generally concentrated on U.S. Forest Service (USFS) and National Park Service (NPS) lands at higher elevations. In the last 30 years, conservation and residential land uses have increased in significance, but in terms of overall area they remain secondary to agriculture.

Methods and Sources

Compared to the rest of the San Pedro River valley, the study area has experienced relatively little historic human activity and scholarly attention, and consequently it is poorly documented in published sources. Prehistoric settlements did exist but are smaller and less studied than sites elsewhere in the valley. The earliest sites of significant historic activity were upstream at Tres Alamos (Tuthill 1947) and downstream at Aravaipa (Hadley, Warshall, and Bufkin 1991). Later, major mines were established to the south (at Cananea, Bisbee, and Tombstone) and to the north (at San Manuel, Mammoth, and Winkelman), but not in the study area. A railroad was contemplated through the area in the late nineteenth century, and a paved highway was planned in the 1960s and again in...