The Beaver Creek Biosphere Reserve and Experimental Watershed is located about 80 km south of Flagstaff in north-central Arizona. The experimental watershed was established in 1956 as a major center for watershed management research within the pinyon-juniper (Juniperus sp.) and ponderosa pine (Pinus ponderosa) vegetation types and semi-desert shrubs. Beaver Creek has a long history of human influence. Since the late 19th century, the area has had various degrees of modification by man, the earliest being the introduction of domestic livestock. Most of the ponderosa pine area has been logged, which has changed its size and age class distribution. Protection from natural fire occurred since the early 1900’s. Pinyon-juniper woodlands were converted for range and water yield improvement in the early 1960’s. Today, the main goals of the Beaver Creek Programme are to provide land managers with essential information about the biological, physical, social, and economic effects of management practices in the ponderosa pine forests and pinyon-juniper woodlands. Furthermore it aims at predicting, displaying, and evaluating differences among the probable results of management alternatives before actions are initiated. Source: UNESCO