GRASS SILAGE 7 



molasses or because it is erroneoush- considered necessary. Frequently this 

 results in excessive drainage from the base and through the walls of the silo; 

 the liquid collects in a low spot in the barnyard and becomes an unmitigated 

 nuisance from the standpoint of odor and flies. 



The problem can be controlled in two ways. The first is to safeguard against 

 excessive seepage beforehand (1) by wilting very succulent crops, (2) by adding 

 some moisture absorbent at chopping time — the incidental absorbent effect of 

 ground grain used as a preservative has been noted earlier in this bulletin; some 

 old hay or straw chopped in with the succulent crop is another expedient, (3) 

 by refraining from adding water except when necessary for dilution of molasses 

 — unlike corn which oftentimes gets considerably dried out before it is ensiled, 

 grasses and legumes do not require additional water; better silage will result if 

 they are not "wet down," and (4) wherever practicable to do so, by having the 

 material that goes into the bottom half of the silo somewhat drier than that in 

 the top half. 



The other method is to provide drainage in the silo bottom for the excess 

 liquid to get away underground. This can be done by having a gravel base 

 which in porous soil will act as a dry well, or by having a tile drain which leads 

 off the seepage to some larger drainage channel such as a ditch or small stream 

 Under no circumstances should any attempt be made to retain the excess liquid 

 in the silo; it is so dilute that the loss of nutrients is very small under most con- 

 ditions of practice, and any saving of nutrients by attempting to make a silo 

 leak-proof is more than offset by deterioration in quality in the lower levels of 

 the mass of silage. The excess liquid makes the silage soggy, sour, and unpalat- 

 able. 



In short, good ensiling practice will shut off seepage at the source if that is 

 possible; if not, make provision to have it drain off freely so that it will not lower 

 the quality of the silage or constitute a nuisance. 



Composition of Grass Silage 



A considerable amount of data has accumulated on this subject since our 

 original bulletin was issued. Table 1 summarizes the composition of silage from 

 various crops analyzed in the course of investigations over a period of nine years. 

 It also indicates some of the changes in composition of the crop which are a result 

 of the ensiling process. 



In general the silages made from grasses, legumes, and small grains were higher 

 than corn silage in all constituents determined except carbohydrates. The low 

 carotene values for potato silage are what might be expected; potato tubers do 

 not contain carotene; the small amount found comes from the relatively small 

 amount of roughage mixed with'the potatoes at chopping time. 



The principal effects of the ensiling process on composition are to decrease 

 the protein and carbohydrates somewhat, and to increase the fat and fiber. The 

 losses are caused by some fermentation of the carbohydrate (which is inevitable 

 in the nature of the process) together with some protein breakdown which ac- 

 companies the fermentation. The gains of fat and fiber are of course relative 

 only; in the case of the fat the increase simply represents a transfer from the 

 carbohydrate, because of the formation from it of certain organic acids such as 

 lactic and acetic, which in conventional methods of analysis are determined as 

 crude fat (ether extract). 



