22 ARID AGRICULTURE. 



however, for they reach so high in the atmos- 

 phere that they catch as much precipitation in a 

 year as falls in humid sections. 



Over much of the region, especially on the 

 higher plateaus and over portions of the Pacific 

 Slope, there is much wind ; while other portions 

 are comparatively free from strong winds. The 

 wind seldom blows hard enough to be destructive, 

 and tornadoes are unknown throughout the 

 mountain regions. Hail and thunder storms are 

 common over a goodly portion of the western 

 prairies and plateaus, and in some sections the 

 farmer should consider the possibility of hail 

 when he selects his principal crops, planting 

 those which will be the least injured. The cli- 

 mate is marked by great freedom from those 

 storms which prove destructive to life and prop- 

 erty in other countries. 



THE The length of season free from frost varies 



from no frost during the year to places with 

 frost every month. Profitable farming may be 

 done where light frosts may occur at any time 

 during the growing months. In middle latitudes 

 where the altitude reaches 7,000 feet to 8,000 

 feet the light frosts of summer are practically 

 harmless to short season crops. The grains and 

 grasses, alfalfa and potatoes, beets and turnips, 

 Canadian field peas and other crops will stand 

 several degrees of frost in the spring. Young 

 seedling plants are not injured by an amount of 



