Pinus monophylla 



P. m. and Juniperus osteosperma 



P. edulis and J. o. 



F-igure 5. — Distribution of the three major tree species in the piny on- juniper woodlands 

 of the Great Basin. 



The variation in tree dominance was assessed on the 18 mountain ranges on which 

 detailed data were collected by dividing the percent cover of either juniper or pinyon 

 by the total tree cover and multipling by 100 (table 4). 



The average relative percent cover contributed by either pinyon or juniper trees 

 shows a definite geographical distribution pattern in the Great Basin (fig. 6). The 

 lowest average relative percent cover of juniper occured in southwestern and central 

 Nevada. Juniper tends to dominate the woodlands in and near the Salt Lake Desert in 



17 



