STEEP TRAILS 



spicuous plants, occur in warm sheltered open- 

 ings in these lower woods, making charming 

 gardens of wildness where bees and butterflies 

 are at home and many a shy bird and squirrel. 



The next higher is the Fir Zone, made up 

 almost exclusively of two species of silver fir. 

 It is from two to three miles wide, has an 

 average elevation above the sea of some six 

 thousand feet on its lower edge and eight thou- 

 sand on its upper, and is the most regular and 

 best defined of the three. 



The Alpine Zone has a rugged, straggling 

 growth of storm-beaten dwarf pines (Pinus 

 albicaulis), which forms the upper edge of the 

 timber-line. This species reaches an elevation 

 of about nine thousand feet, but at this height 

 the tops of the trees rise only a few feet into 

 the thin frosty air, and are closely pressed and 

 shorn by wind and snow; yet they hold on 

 bravely and put forth an abundance of beauti- 

 ful purple flowers and produce cones and 

 seeds. Down towards the edge of the fir belt 

 they stand erect, forming small, well-formed 

 trunks, and are associated with the taller two- 

 leafed and mountain pines and the beautiful 

 Williamson spruce. Bryanthus, a beautiful 

 flowering heathwort, flourishes a few hundred 

 feet above the timber-line, accompanied with 

 kalmia and spiraea. Lichens enliven the faces 



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