THE COAST FOREST 249 



is the growth denser, the boles less tapering and cleaner 

 of branches, and less knotty. 



This generally undesirable development, due to open 

 stand, is probably caused less by climate than by soil. 

 The soil overlying the rocks of the rugged slopes is 

 scanty, and becomes more and more so as we go 

 north, until finally only the muck of decayed moss and 

 other vegetation furnishes a foothold for the trees. In 

 consequence, fallen timber frequently makes travel im- 

 possible. 



The underbrush and lower vegetation is often dense 

 and luxuriant, comprising species of Vaccinium, Rubus, 

 RibeSy Menziesia and the spiny Echinopanax horridum, 

 which was found as far north as Point Gustavus in Glacier 

 Bay. A heavy cover of moss hides the mucky soil, which 

 is wet probably all the year. 



Now and then swamps occur, which, so far as tree 

 growth is concerned, show only dwarfed specimens of 

 Pinus contortd) or possibly of hemlocks. Along the shores 

 and in the river bottoms deciduous trees and shrubs 

 relieve the monotony of the evergreens, among which 

 occasional clumps of Pyrus rivularis, Sambucus pubens, 

 Sorbus sambucifolid) and Viburnum pauciflorum and in 

 the lower latitudes Oregon alder are observed. Cot- 

 tonwoods {Populus trichocarpa and balsamifera) form 

 groves on the flats as far west as Kadiak Island, and wil- 

 lows, shrubby and in tree form {Salix sitchensis and alax- 

 ensis), fringe the water courses; and whatever other 

 space is left open, high or low, wet or dry, is at once oc- 

 cupied by the ubiquitous shrubby alder (Alnus sinuata) 

 with its many stout stems forming impenetrable thickets. 



One of the most interesting examples of the evolution 

 of a forest growth in progress, which the writer had the 

 opportunity to study, was found in Glacier Bay. The 

 peninsula known as Point Gustavus which juts out from 



