MOUNTAIN TREES 



distance along the mountain streams, 

 especially on the desert slopes, where 

 it endures with remarkable fortitude 

 the hot summer days. How refreshing 

 the bright, green groves of cottonwoods 

 must have been to the early western 

 travellers as they approached the moun- 

 tains after their long journey over the 

 parched deserts ! 



With the latter and ascending farther 

 up the mountain streams is the Black 

 Cottonwood (Populus trichocarpa)* 

 It is a tree of more regular form with 

 many ascending branches and broad 

 crown. The lilac-like leaves are dark 

 green and shining above but whitish be- 

 neath. It is often called Balm or Bal- 



*Grinnell in his Biota of the San Bernardino Moun- 

 tains records the occurrence of a cottonwood in Fish 

 Creek Canyon from 7200 to 8000 feet altitude, which is 

 a variety of the P. trichocarpa. "The leaves were very 

 much larger and fewer in number, and there was a far 

 greater amount of balsam in the winter buds, so that 

 the unfolding leaves were extremely sticky with it. The 

 air in the vicinity was strongly charged with the char- 

 acteristic odor far more than with trichocarpa. The 

 trunk was larger in proportion to the height of the 

 tree, smooth barked, and mostly green." A narrow-leaf 

 variety (P. trichocarpa VAR. ingrata) is found in the 

 upper Santa Ana Canyon at the mouth of Nork Fork. 



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