STUDY AREA 



The study area chosen lies within the boundaries o£ the Great Basin portion of the 

 Basin and Range Province (Hunt 1974), and encompasses 100,437,610 acres (40,663,000 ha) 

 (fig. 1). Sampling for this study was restricted to areas where stands of vegetation 

 were occupied by any one or any combination of the species Finns edulis, Pinus 

 monophylla, and Juniperus osteosperma. 



The topography of the Great Basin typically consists of linear, north-south 

 oriented mountain ranges separated from one another by dry desert valleys (Thornbury 

 1965). The ranges vary in size, but are commonly 50 to 75 miles (80 to 120 km) long 

 and 6 to 15 miles (10 to 25 km) wide (Lustig 1969). The mountain ranges rise 6,000 to 

 14,000 feet (1,800 to 4,300 m) above sea level. The details of the geologic origin of 

 the Basin and Range Province are described by Noland (1943) and Hunt (1974) . The rocks 

 which make up these ranges are largely of sedimentary origin, but many ranges consist 

 partly of wholly of igneous rocks (Hunt 1974) . 



Basic climatic patterns in this area are described by Wernstedt (1960) and 

 Houghton (1969) . An outline of the overall floristics of the Great Basin is discussed 

 in Cronquist and others (1972) . The general vegetation patterns in relation to 

 environment are discussed by Billings (1951) and Young and others (1976) . 



Figure 1. — Map showing the 

 mac or mountain ranges in 

 the studied portion of 

 the Great Basin. The 

 lower moimtain boundaries 

 are the same as those in 

 Cronquist and others (1972). 

 The 66 mountain ranges 

 ohosen for this study are 

 unshaded and numbered. 

 See table 1 for the names 

 of the studied mountain 

 ranges. 



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