DRY-FARMING 



material and for decorative purposes. 

 Hardy, drought -resistant trees, such as 

 honey-locust, Russian mulberry, black 

 locust, green ash, hackberry, bon-elder, 

 yellow pine, Scotch pine and jack pine 

 have been most frequently used. Cotton- 

 wood, silver maple, and Lombardy poplar 

 have been planted where the land hap- 

 pens to be moist. It has been clearly 

 demonstrated that thorough and fre- 

 quent cultivation to form a soil-mulch 

 and so check evaporation is essential for 

 successful tree-growth on the semi- arid 

 plains. Furthermore, the deodar cedar 

 and coulter pine have been planted ex- 

 perimentally by the Forest Service in 

 southern California; and although the 

 experiments have been conducted for a 

 comparatively short time, the results show 

 that both these trees are well adapted to 

 the rather trying conditions of that 

 region. Other species which are being 

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