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WILLIAM S. COOPER 



be seen. Beginning with the latest, we find poorly developed 

 areas of climax forest of the subalpine type. Picea Engelmanni 

 is by far the most abundant, but Ahies lasiocarpa and Pinus 

 albicaulis also occur sparingly. The trees are widely scattered — 

 much more so than upon the neighboring moraine, and between 

 them is found the same thicket growth that occurs upon the 

 moraine. Betula glandulosa is dominant, and Salix spp. and 

 Shepherdia canadensis are common. The soil to a depth of 

 two or three inches has much humus, and the ground cover is 



Fig. 8. Shingle flat protected from erosion by moraines of Robson Glacier. 

 At right, poorly developed climax forest and Salix-Betula thicket; at left, lane- 

 like opening with sparse vegetation— a premorainal stream channel. 



fairly continuous. Dryas octopetala is commonest, and Dryas 

 Drummondii, Ardostaphylos rubra, Hedysarum Mackenzii, Silene 

 acaulis, and Castilleja pallida occur frequently. This forest of 

 poorly developed climax nature is found in irregular patches 

 upon the areas a trifle higher than the rest. Between them are 

 anastomosing channel-like slight depressions, which if traced 

 to the moraine are seen to disappear beneath it. These are 

 practically treeless except for scattered young spruces, and the 

 effect is of lane-like openings between patches of large trees and 



