CLIMAX COMMUNITIES : PRESENT DISTRIBUTION 277 



forest is indicated by the luxuriant vegetation of the Olympic 

 Peninsula. Here the ranges of all the major species overlap and 

 most of the trees attain their maximum size. The climax dominants 



FlG. 144. Douglas fir (Pseudotsnga) and western arborvitae (Thuja pli- 

 cata) in the coastal montane forest. Snoqualmie National Forest, Wash.— 

 U. S. Forest Service. 



are western hemlock (Tsuga heterophylla), arborvitae (Thuja pli- 

 cata), and grand fir (Abies grandis). Subordinate broad-leaved spe- 

 cies and many herbaceous species are associated in abundance. 133 

 Douglas fir, which reaches its greatest size here, is the most abun- 

 dant and widespread species, but it occupies drier sites, is relatively 



