74 SOILS 



tions on the agricultural value of these soils, or 

 they may indicate a weakness where none is sus- 

 pected. It is well to take a dozen or more samples 

 of soil from different parts of a field in which the 

 soil is all approximately similar, to mix them and to 

 take from the combined lot the sample of soil that is 

 tested. This makes it quite certain that the re- 

 sults obtained represent the field fairly. 



The Bureau of Soils of the United States De- 

 partment of Agriculture is making a "soil survey." 

 The types of soils in all the important agricultural 

 sections of the country are being studied. About 

 100,000 square miles of land in different states 

 have already been studied and reports issued. 

 These reports should be very useful to the farmers 

 in these sections. They may be obtained of the 

 Division of Publications, Washington, D. C. 



