GENERAL FOREST ASPECTS 



85 



ciers. The marks of previous glaciation are extensive and con- 

 spicuous. Numerous lakes, large and small, are fed by cold 

 mountain streams, many of which flow from glaciers or perpetual 

 snows. There are many cirque basins occupied by deep, cold 

 and dark waters and fringed by forests of fir and spruce. 

 Table 13. Forests of the Flathead Section. 



In this section it will be observed that the white pine, grand- 

 fir, hemlock and arbor vitae are still present but in greatly 

 reduced amounts. Larch and spruce are the main species with 

 lodgepole pine locally dominant. The white pine formation 

 appears usually in the narrower valleys and canyons, protected 

 from excessive influence of wind and sun. The essentially moist 

 condition of the soil is maintained, and atmospheric moisture is 

 relatively high. While the white pine is a less common tree 

 than in some other sections, yet some of the largest trees are 

 found, one on McDonald Creek in Glacier Park measuring seven 

 feet in diameter. Hemlocks also reach a large development in 

 Glacier Park, as in the case of a grove near Avalanche Basin, 

 where some of the trees are three feet or more in diameter. 



The ranges in altitude will be noted. In nearly all of the 

 species the lower limit is near the lowest possible altitude in 

 the section. The upper limit in some of these cases extends to 

 the uppermost altitude habitable by trees. This range differs 

 but little in different parts of the section. 



