62 DRY-FARMING 



developing the principles uj)on which successful dry- 

 farming rests. Further, it may be said that while 

 in the humid East the farmer must be extremely 

 careful not to turn up with his plow too much of 

 the inert subsoil, no such fear need possess the 

 western farmer. On the contrary, he should use 

 his utmost endeavor to plow as deejjly as possible 

 in order to prepare the very best reservoir for the 

 falling waters and a j^lace for the development of 

 plant roots. Figure 18 shows graphically the dif- 

 ference existing between the soils of the arid and 

 humid regions. 



Gravel seams. — It need be said, however, that 

 in a number of localities in the dry-farm territory 

 the soils have been deposited by the action of running 

 water in such a way that the otherwise uniform 

 structure of the soil is broken by occasional layers 

 of loose gravel. While this is not a very serious 

 obstacle to the downward penetration of roots, it 

 is very serious in dry-farming, since any break in 

 the continuity of the s(jil mass prevents the upward 

 movement of water stored in the lower soil depths. 

 The dry-far'mer should investigate the soil which he 

 intends to use to a dej^th of at least 8 to 10 feet to 

 make sure, first of all, that he has a continuous soil 

 mass, not too claj^y in the lower depths, nor broken 

 by deposits of gravel. 



Hardpan. — Instead of the heavy clay subsoil of 

 humid regions, the so-called hard]jan occurs in 



