FACTORS IN WHEAT PRODUCTION 117 



farmers the term commercial fertilizer is practi- 

 cally unknown. Such is not the case, however, 

 in the Eastern states. There fertilizers present 

 an important item of cost in wheat production. 

 The following table shows some marked contrasts 

 in the cost per acre in selected states. 1 



Commercial Fertilizers in Wheat Production, 1909 



It is readily seen that the states which can pro- 

 duce profitable crops without the use of commer- 

 cial fertilizers have a distinct advantage in cost 

 of production. In such regions care should be 

 taken to postpone as long as possible the time when 

 the use of such fertilizers will become necessary. 

 Careful tillage, scientific crop rotation, and the 

 use of barnyard manure should be practiced. 



The Effect of Irrigation on Wheat Production. - 

 Where the supply of moisture is deficient, irriga- 

 tion is necessary. This is the case in many of the 

 valleys of the western mountain states. Al- 



1 Crop Reporter, May, 1911. 



