THE YOSEMITE FLORA 3 



including the Wawona, Yosemite, and Hetch Hetchy valleys are 

 within its confines. There is a strong infusion of foothill species, 

 however, in these lower districts, particularly on warm walls and 

 gravelly slopes. As indicated by its name, this is primarily a 

 forest belt, dominated by the Yellow Pine, one of the noblest of 

 our coniferous trees and the most widely distributed of them all. 

 Within this zone occur not only the largest trees and the grandest 

 forests of which any country can boast, but also the greatest 

 variety of cone-bearing species. Restricted to it are such well- 

 known representatives as the Big Tree, Sugar Pine, White Fir, 

 Douglas Fir, and Incense Cedar, each with its own peculiar 

 attractions and all conspiring with the Yellow Pine and with 

 each other to form open, airy, balsam-scented forests. Along the 

 streams grow such trees as the Nuttall Dogwood, with its showy 

 masses of pure-white bloom, the White Alder, the Black Cotton- 

 wood, and many sorts of willows, while among the flowering 

 shrubs of this belt are the Azalea, the Deer-brush, the Choke- 

 cherry, the Thimble Berry and many others. Along its lower 

 borders the Yellow Pine Belt meets that of the foothills at alti- 

 tudes averaging 3000 feet, as along El Portal Road, but in other 

 places it varies from 2000 to 5000 feet, as already indicated. Its 

 upper limits occur at about 6200 feet, although the belt may be 

 continued upward to 7000 or 8000 feet on warm slopes, or it may 

 be depressed to as low as 4000 feet along cold streams or valleys. 

 The upper edge of this belt is well defined where it crosses the 

 Yosemite Falls Trail at about 5000 feet altitude. As one ascends 

 the trail, he notes such species as Douglas Fir, Incense Cedar, 

 California Laurel, Broad-leaf Maple, Sword-fern, Wild Ginger, 

 and Soap Plant. All of these are plentiful until the 5200-foot 

 contour is reached, but not one of them occurs much above this 

 altitude. 



3. Upper Coniferous Belt (Canadian and Hudsonian Life 

 Zones). Only species of boreal origin are found in this belt. On 

 ascending the trails from the lower valleys, it gradually dawns 

 upon one that he is passing into a new world. One by one the 

 familiar plants of the Yellow Pine Belt drop out, their places in 

 the forest being taken by new forms. The Yellow and Sugar 

 pines are here replaced by the Jeffrey, and that in turn by the 

 Silver Pine; no longer do we see the Black Oak with its tall 

 trunk and spreading crown, but in its place are thickets of the 

 dwarf Huckleberry Oak; the white-plumed Deer-brush remains 

 only as a memory, its mantle having descended to another Cean- 

 othus, the compact, intricately branched Snow-bush, and many 

 lesser sorts of annual and perennial herbs occur only at these 

 higher levels. This is the Upper Coniferous Belt, characterized 



