FOREST TREES OF THE PACIFIC SLOPE. 



353 



OCCUKBENCE. 



Borders and vicinity of low mountaia and higher foothil! streams and valleys; in 

 sandy, fertile, fresh soils (here largest), or in dry, gravelly ones (shrubby). Grows in 

 extensive pure thickets and clumps, interspersed with black haw, Oregon crab, Garry 

 oak, western choke cherry, and occasional gray pine. 



Fig. 166. — Primus subcordata. 



Climatic Conditions. — Similar to those of choke cherry. 



Tolerance. — Endures light shade, which is helpful in seedling stage. 



Reproduction. — Prolific periodic seeder in better soils, but fruits sparingly and Irregu- 

 larly in poor, dry soils. Seedlings fairly abundant in fresher soils; very scarce in dry 

 places. 



