SINO-MONGOLIAN FRONTIER 



Spruce (Picea sp.) and Larch {Laryx sp.). These 

 trees occur at altitudes of from 5,000 feet upwards, 

 usually growing on slopes exposed to the north, 

 which, remaining snow-covered all the winter 

 and late into spring, are always more moist than 

 those facing south, where the snow usually melts 

 a few hours after it has fallen. Though these 

 forests are often very extensive, the trees seldom 

 attain a growth of more than two feet in diameter. 

 Large areas of forest, consisting of one or other 

 of these species, is the rule, but not infrequently 

 mixed forests occur. 



The lower slopes in these forest areas are often 

 clothed with the Common Pine (Pinus sylvestris), 

 while it is nearly always this tree that goes to 

 make up the woods round temples in the foothills. 

 This tree is prized above either of the foregoing 

 species as a wood producer. The woodcutters 

 strip the saplings of their lower branches, which 

 causes them to grow very tall and straight. 



In Shansi one also comes across the peculiar 

 ^Vhite-barked Pine (Pinus hungeana). It is char- 

 acterized by having a three-needled leaf, and by 

 its smooth silvery-white bark. This tree is very 

 rare indeed. 



In Shensi I came across a small member of the 

 genus Pinus, which grows on rocky cliff surfaces, 

 and is characterized by having five or seven needles. 

 This also seems to be a rare species. 



In the foothills and on the plains of Shansi and 



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