144 SOILS 



What inoculation of the soil means. Not all soils con- 

 tain just the sort of bacteria needed for the legume that 

 you may desire to grow. Some soils never have had 

 legumes growing in them, and hence, the particular bac- 

 teria needed may not be present then at all. If this is the 

 case, the crop will do but poorly, especially if the land is 

 old, deficient in vegetable matter, and worn out. To 

 prepare the way, the soil must be inoculated : bacteria 

 must be introduced into the land. You know how the 

 yeast plant is employed in bread-making, just a tiny 

 bit of it is used. When warmth and moisture are sup- 

 plied these yeast plants develop rapidly and soon leaven 

 the whole. So with the bacteria of the legumes. In the 

 first instance, with no yeast, there can be no "rising" of 

 the bread, while in the second, with no bacteria those of 

 the right kind in the soil, there can be no formation of 

 the tubercles on the roots of the legume. Hence, the need 

 of inoculation, if the wished-for end is to be attained. 



Each legume has its own worker. One of the first 

 steps of inoculation is to get the right bacteria, for the 

 reason that each legume has its own bacteria with which 

 it works personal servants peculiarly loyal and devoted 

 to it. Thus the bacteria that are allied with the cow peas 

 positively refuse to labor with the alfalfa or with the 

 clovers. These bacteria would rather die, than seek 

 dwelling places on the roots of either alfalfa or clover. 

 But the same peculiarity is true of alfalfa and clover bac- 

 teria: these behave in precisely the same way to the cow 

 pea or to the soy bean, as their relatives do to their lords 

 and masters. In other words, each legume becomes a 

 favorite abiding place for some special kind of bacteria, 

 and long coaxing is necessary in order to get them to do 

 differently. In a few cases bacteria are known to be more 

 plastic, burr clover and sweet clover being two exam- 



