OCT., 1899.] 



WHITE-r.ARK PIXE BELT. 



30 



11011 Bailey, in following' the w agou road around the inouiitaiu, passed 

 through a belt of it about 8 miles iu length. It begins 3 miles 

 northeast of Ash Creek at an altitude of about 5,400 feet and reaches 

 northerly to about 3 miles northwest of Incon stance Creek, where 

 it ends abruptly at an altitude of 5,000 feet. Here it is the dominant 

 tree, and in half of it the only tree. This area is covered during the 

 latter part of the afternoon by the shadow of the mountain, and conse- 

 quently is colder than places of equal altitude farther north or south. 

 The soil is sandy and barren and the trees are of small size. 



(3) The Upper Belt or Belt of White-Bark Pines {Finns alMcaulis). 



Still above the forest of Shasta firs, braving its way upward over the 

 bare rocky ridp-^s into the very teeth of the domain of perpetual snow, 

 is another timber belt — an c pen belt of straggling, irregular trees, whose 



whitened, twisted trunks with their storm-beaten heads of green are 

 among the most weirdly picturesque objects on the mountain (fig. 20). 

 The tree is the timberline white-bark pine, which, wherever found, 

 pushes its way over steep and barren slopes to the extreme upper limit 

 of tree growth. 



At the lower part of its range it forms an almost continuous though 

 narrow belt around the mountain, and often attains a height of 30 or 40 

 feet and a diameter of 2 feet. In the higher parts of its range it soon 

 becomes restricted to the ridges, leaving the intervening basins and 

 gulches bare, and as it climbs higher and higher becomes more and 

 more reduced iu size and undergoes material changes of form and posi- 

 tion. At certain altitudes the slanting trunks, only 4 or 5 feet in 

 height, serve as pillars to support the flattened tops which form a 

 canopy of intertwined and matted branches (lig. 21). 



