In this paper, we describe and present the results of our effort to establish a spatial delineation of the Mogollon Highlands region—an ecologically fascinating North American transition zone of continental importance. is dramatic landscape of escarpments, canyons, mesas, deserts, and high conifer forests—where the Sonoran Desert of the Basin and Range Province meets the redrock country of the Colorado Plateau and the Southern Rocky Mountains, where the northern limits of some species…

Buffelgrass loves south-facing hillsides in the Sonoran Desert, especially in Sonora. In some cases it replaces nearly all native vegetation except older trees and cactus that persist from before the invasion took place.

This area was cleared and tilled for buffelgrass. Now it is a virtual monoculture of buffelgrass, which provides poor forage for cattle, the whole point of the operation.

The Rock Horned Lizard (Camaleón de Piedra, in Spanish), Phrynosoma ditmarsi, is a poorly known Mexican endemic species with a distribution restricted to the state of Sonora. The International Union for Conservation of Nature (IUCN) has categorized this species as Data Deficient (Frost et al., 2007), but using the Environmental Vulnerability measure (EVS) Wilson et al. (2013) assessed this species with a score of 16, placing it in the middle portion of the high vulnerability…

RESUMEN

Vivimos en el Antropoceno. La superficie completa de la tierra ha sido impactada por la actividad humana y nuestro uso del suelo. En este con- texto, la mayoría de los pastizales en zonas áridas y semiáridas tienen procesos de degradación. Este trabajo describe los cambios provocados por la antropización del paisaje en pastizales del norte de México y Suroeste de Estados Unidos, y la forma como se comporta la hidrología de ellos ante diferentes intensidades de…

Boundary Surveys

The Treaty of Guadalupe Hidalgo in 1848 at the end of the United States-Mexico War established the boundary between the two nations, and expanded the United States to the Pacific Ocean. In 1853, the Gadsen Purchase added the area along the modern Arizona-New Mexico-Sonora border to the United States. The expeditions to survey the border between 1848 and 1855 were the rst biological inventories of the borderlands. Many common Sky Islands plants were…