RELATION OF WINDS 



47 



fall decreases. Over the larger part of the arid and 

 semiarid sections the sun shines over 70 per cent of 

 the time (Fig. 16). 



Winds 



The Avinds of any locality, owing to their moisture- 

 dissipating power, play an important part in the 

 success of dry- 

 farming. A per- 

 sistent wind will 

 offset much of 

 the benefit of a 

 heavy rainfall 

 and careful cul- 

 tivation.. While 

 great general 

 laws have been 

 formulated re- 

 garding the movements of the atmosphere, they are 

 of minor value in judging the effect of wind on any 

 farming district. Local observations, however, may 

 enable the farmer to estimate the probable effect of 

 the winds and thus to formulate proper cultural 

 means of protection. In general, those living in a 

 district are able to describe it without special obser- 

 vations as windy or quiet. In the dry-farm terri- 

 tory of the United States the one great region of 

 relatively high and persistent winds is the Great 

 Plains region east of the Rocky Mountains. Dry- 



FiG. 16. 



sunshine. 



lal number of hours of 

 (Cyclo.Ani. Agr.) 



