250 



THE ESSENTIALS OF AGRICULTURE 



which may be converted into sugar. Very soon after forage has 

 been put into the silo the sugar is acted upon by bacteria and 

 is, in part at least, converted into acid. One may ask why it 

 is necessary to exclude the air if the acid preserves the silage. 



When air is admitted, the 

 acid is destroyed by molds 

 which feed upon it. With 

 the acid destroyed, the bac- 

 teria that cause decay, known 

 as putrefactive bacteria, at- 

 tack the protein and cause 

 the silage to spoil. This may 

 explain why clover, alfalfa, 

 cowpeas, and soy beans do 

 not keep well in the silo. 

 These materials probably do 

 not contain enough sugar 

 to produce the acids required 

 to preserve them. These 

 legumes keep well when 

 mixed with corn, sorghum, 

 or other materials containing 

 sugar. 



324. The advantages of 

 the silo. 1 A well-managed 

 silo makes it possible for its 

 owner to secure many im- 

 portant advantages. More 

 feed can be stored in a given 

 space in the form of silage 



than in the form of hay. The space required to store one ton 

 of hay will hold eight tons of silage. An acre of corn can be 

 placed in the silo at less cost than the same area can be husked 

 and shredded. Crops can be put into the silo in weather that is 



1 Adapted principally from Farmers' Bulletin 556, United States Department 

 of Agriculture. 



FIG. 119. A hollow-tile silo 



