10 MASS. EXPERIMENT STATION BULLETIN 362 



The grass on the entire field was cut and one half of it was cured and stored as 

 hay, while the other half was put into the silo with molasses. The grass that 

 went into the silo was stored within a few hours after cutting; that made into hay 

 lay out for four days and was exposed to rain four times with considerable extra 

 handling as a consequence. The results of analyses of the grass, hay, and silage 

 are expressed in the table as percentages of the dry substance which each con- 

 tained. This is the only possible basis of comparison since the water content 

 of the grass and the silage was about three times that of the hay. 



Table I. — Composition of Fresh Grass and Grass Stored as Hay and 

 AS Silage 



Percentage in Dry Matter 



Protein Fat Fiber Carbo- 



hydrates 



Fresh mixed grass 11.9 2.3 34.4 43.6 7.9 



Hay made from half the lot of 



grass 9.5 1.9 36.5 46.1 6.0 



Silage made from the other 



half 10.7 3.5 34.7 42.2 8.9 



A study of the table shows that : 



1. The protein content of the grass made into hay was reduced approx- 

 imately one fifth, while that of the grass made into silage was reduced about 

 one tenth. 



2. The crude fat (which, by the way, is largely coloring matter rather than 

 true fat) was reduced roughly one sixth in the hay. The increase of this con- 

 stituent in the silage is apparent only, probably being due for the most part to 

 the presence of waxy or resinous material in the added molasses. 



3. The fiber (of which a minimum is desired) was practically unchanged in 

 the silage, and was increased relatively in the hay, owing to the loss of other 

 soluble and more valuable constituents. 



4. There was a loss of about 3 percent of the carbohydrates in the silage. 

 The gain in this constituent in the hay is relative only, as explained above for 

 fiber. The whole story of hay losses does not appear here, for because of a fire 

 which destroyed the barn in which the hay was stored, samples of the hay after 

 several months storage were not available for analyses. It is generally recognized 

 that in the sweating process which hay undergoes in the mow, considerable of 

 the carbohydrate portion is used up. 



5. About one fourth of the minerals were leached out of the hay by the 

 four-day exposure. As in the case of the fat, the increase in minerals in the 

 silage is apparent only, being due to the presence of a considerable amount of 

 these substances in the added molasses. The minerals and the waxy or resinous 

 material, referred to above, represent the portion of the molasses which is not 

 broken down by the fermentation, being left behind as a residue. 



It is to be regretted that actual tonnage losses by both methods of storage are 

 not available. As already noted, the hay was destroyed by fire, but losses in the 

 silo for the 1937 season have been ascertained. The loss in dry matter was 13.5 



