SILOS AND SILAGE 



155 



development of our livestock industry that has come since the 

 introduction of modern agricultural machinery (Figs. 30 and 31). 

 The silo is most economical where the number of stock kept is 

 sufficiently large to consume at least 100 tons of silage during the 

 season. The investment in a silo and necessary machinery is rela- 

 tively high for smaller silos, and the cost of storing and loss of silage 

 through spoiling relatively larger than with large silos. The silo 

 belongs with intensive farming, where the greatest profit results 

 from keeping as large a number of livestock as possible on a given 

 acreage. 3 For small herds of, say, 12 head of cattle or less, the 

 growing of roots where the land is suited to these crops may prove 

 a more economical practice for supplying succulence in the rations 

 fed than making silage. 



FIG. 31. Battery of four cement silos on a California cattle ranch. Dimensions 20 feet in 

 diameter, and 60 feet high, capacity about 400 tons each. (Pacific Rural Press) 



SILAGE CROPS. Indian corn is preeminently the great 

 American silage crop and is, in general, better adapted for siloing 

 purposes than any other agricultural crop. The reason for this is 

 easily seen : The thick stems and broad leaves of the corn plant, 

 when cut, pack well in the silo; corn is rich in starch and other 

 non-saccharine carbohydrates, which insures silage of a moderate 

 acidity, and it is relatively low in protein substances, so that the 

 danger of undesirable fermentations in the silo is removed. The 

 acids normally present in corn silage are lactic and acetic. Lactic 

 acid is non-volatile and makes up 'about two-thirds of the acidity of 

 silage made from nearly matured corn, or about 1 per cent on the 

 average, while acetic acid is present in from 0.2 to 0.5 per cent on 



3 Bureau of Statistics, U. S. Department of Agriculture, Bulletin 73, p. 37. 



