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UNIVERSITY OF COLORADO STUDIES 



of the morainal ridges on the four sides of the lake. The ridge to the 

 south separates the lake from Bog Lake, a small glacial pond in about 

 the same ecological stage. Bog Lake is higher than Redrock Lake; 

 the outlet from it does not flow into Redrock Lake, however, but into 

 the wet meadow to the west. Redrock Lake has no stream inlet; 



Fig. i. — Map of Redrock Lake Showing Plant Zones 

 The enclosed areas in the lake are groups of water lily leaves; dotted areas represent 

 sedges; horizontal shading represents shrubs. Outside of the shrub zone is forest, the 

 exact character of which is discussed in the account of zonation. The small squares, 

 each with a dot in the center, indicate stakes or stations used in making the survey. 



it receives its water supply by seepage, mainly from the wet meadow 

 and from the run-off of the bounding moraines. The outlet is at the 

 northwest side through the low north ridge (see Fig. 1). 



Water Level. — In the spring and early summer the lake is usually 

 overflowing but in the late summer and autumn little or no water leaves 



