To the Corner of the Province: The 1780 Ugarte-Rocha Sonoran Reconnaissance and Implications for Environmental and Cultural Change

In April 1780, Military Governor Ugarte and Chief Engineer Rocha were sent on a reconnaissance mission through the northwestern frontier of New Spain, land that today is northern Sonora and southeastern Arizona. Seeking information on the advisability of placing a presidio at the junction of the San Pedro and Gila Rivers, Ugarte and Rocha described the landscape in unprecedented detail. Their accounts provide valuable baseline information on environment and culture that allows for analysis ...