424 



FOREST TREES OP THE PACIFIC SLOPE. 



OCCURRENCE. 



On borders of desert streams and sinks; in gravelly or loamy soils. Forms open groups 

 and patches of pure growth, or occasionally interspersed with desert willow and cotton- 

 wood. 



Climatic Conditions. — Endures climatic conditions marked by high summer tempera- 

 ture, rapid evaporation, small rainfall, dry atmosphere, and mild winters. Nothing is 

 known now of silvical characteristics and reproduction. 



