114 AGRICULTURE. 



"The way in which the liquid culture may be 

 introduced into the soil varies somewhat with 

 the character of the seed to be used and the 

 area of the field to be treated. With large seed 

 it is often more convenient to simply soak them 

 in the fluid, or moisten them with it, and then, 

 after they are sufficiently dry, to sow them in 

 the ordinary way. In other cases it is frequently 

 more feasible to introduce the liquid culture 

 directly into the soil. This may be done by 

 spraying, or perhaps a simpler method is to mix 

 the culture thoroughly with a wagon-load of 

 earth, and then to distribute and harrow this in, 

 just as a fertilizer would be handled."* 



III. Other Conditions. 



It may be possible that some condition of the 

 soil prevents the healthy growth of the species 

 of bacteria. They require an abundant supply 

 of air (see "Tillage") and plenty of moisture, 

 though this should not be present in sufficient 

 quantities to prevent the free circulation of the 

 air. They will not thrive in an acid soil; hence, 

 if difficulty is found in growing leguminous 

 crops, it would be well to give the soil a light 

 application of lime if it is not known to already 

 contain it. 



* Year-book, United States Department of Agriculture, 1902, 

 p. 341- 



