44 AGRICULTURE 



can easily hold a clear title to a farm by the time one is of 

 age and have it well improved before middle age. 



2. Dry-Farming 



By dry- farming is meant the management and carrying 

 on of agriculture, such as the production of field crops, 

 vegetables and fruit, and the raising of stock, in regions 

 where the rainfall is not sufficiently heavy for successful 

 plant growth and crop production under the common meth- 

 ods of farming especially the careless methods followed 

 in some sections of our country where rainfall and soil 

 conditions are more encouraging for profitable crop pro- 

 duction. 



The use of terms. Territory that has an annual 

 rainfall of above 30 inches is called humid and will do well 

 under ordinary agricultural practises. Regions that receive 

 less than 10 inches of rainfall annually are called arid, and 

 can not be successfully farmed by the methods now known 

 without irrigation. Regions that receive from 10 to 20 

 inches annually are called semi-arid, and those that receive 

 from 20 to 30 inches, sub-humid. By the best methods now 

 known to dry-farming practise, most semi-arid and sub- 

 humid land may be successfully and profitably farmed. 

 Some of the common methods will not serve where the an- 

 nual rainfall is less than 30 inches. 



A surprisingly large proportion of the land surface of 

 the earth is either arid, semi-arid, or sub-humid. The fol- 

 lowing table gives the proportions of the earth's surface re- 

 ceiving varying amounts of precipitation: (Widtsoe, Dry 

 Farming. ) 



Annual Precipitation Earth's Surface 



Under 10 inches 25 per cent. 



From 10 to 20 inches 30 per cent. 



