168 FORAGE CROPS 



time, and investigation of the composition of 

 the two showed that this difference was due to a 

 larger proportion of nitrogenous substance in the 

 clover than in the timothy. 



It is now known that the individual members of 

 this group of plants possess the peculiar property 

 of being able to secure the important element ni- 

 trogen, in part, at least, from the air. Therefore, 

 they may not need nitrogenous fertilizers after they 

 are well established, and they may add to the 

 nitrogen content of the soil when they are returned 

 to the earth. The advantage of leguminous crops 

 to the feeder lies in the fact that the plants 

 themselves contain a larger proportion of nitroge- 

 nous matter than those of the grass family, and 

 thereby may be used to supplement other foods 

 and to reduce bills for purchased and concentrated 

 feeds. One can more profitably utilize the carbo- 

 hydrates usually contained in excess in other 

 plants; and he is relieved of some of the necessity 

 of purchasing nitrogenous fertilizers to increase 

 the growth of the cereal crops. 



Soil inoculation 



While leguminous crops possess this superior 

 advantage in the ability to appropriate nitrogen, it 

 must be remembered that this power is not constant 

 for all soils and under all conditions ; but in order 



