28 DRY-FARMING 
were needed for the lively interest taken in the sub- 
ject of dry-farming, it is amply furnished by these 
figures showing the vast extent of the country 
interested in the reclamation of land by the methods 
of dry-farming. As will be shown below, nearly 
every other large country possesses similar immense 
areas under limited rainfall. 
Of the one billion, one hundred and ninety-one 
million, four hundred and fifty-seven thousand, two 
hundred and eighty acres (1,191,457,280) repre- 
senting the dry-farm territory of the United States, 
about 22 per cent, or a little more than one fifth, is 
sub-humid and receives between 20 and 30 inches of 
rainfall, annually; 61 per cent, or a little more than 
three fifths, is semiarid and receives between 10 and 
20 inches, annually, and about 17 per cent, or a little 
less than one fifth, is arid and receives less than 
10 inches of. rainfall, annually. 
These calculations are based upon the published 
average rainfall maps of the United States Weather 
Bureau. In the far West, and especially over the 
so-called ‘‘desert”’ regions, with their sparse popula- 
tion, meteorological stations are not numerous, nor 
is it easy to secure accurate data from them. It is 
strongly probable that as more stations are estab- 
lished, it will be found that the area receiving less 
than 10 inches of rainfall annually is considerably 
smaller than above estimated. In fact, the United 
States Reclamation Service states that there are only 
