12] 



VEGETATIONAL TYPES OF TEMPERATE LANDS 



377 



makes for varied groupings, there is a tendenc)' towards pure con- 

 sociations near the timber-Hne ; at its upper levels the forest also 

 becomes less luxuriant and the canopy lower, until it passes into 

 ' elfin wood ' and ultimately ' Krummholz ' of stunted and twisted 

 trees {see Fig. io8) about where the alpine tundra begins. How- 

 ever, mountain vegetation has no uniform pattern but varies from 

 range to range. Thus in many mountainous regions of the temperate 



Fig. io8.- I'hk 



Cooper.) 



untains. (Phot. 



belt, as for example in central Europe and the White Mountains 

 of New England, there is a tendency for the lower zone of montane 

 forest, like the basal tracts, to be dominated by broad-leafed 

 deciduous trees, and only the higher (subalpine) levels to be pre- 

 dominantly coniferous. Often a fairly wide belt of mixed deciduous 

 and evergreen forest intervenes ; and although there is a general 

 tendencv for corresponding zones to decrease in altitude towards the 

 poles, there mav be wide variation according to local conditions 

 even on the selfsame line of latitude. 



Further Consideration 



Although this chapter represents in outline the results of considerable 

 reading and personal experience, often in obscure periodicals or remote 



