34 FORAGE CROPS 
with the season and kind of crop, nevertheless 
the cost of dry matter in the various crops, not 
including the labor required to bring the food to 
the barn, averaged about $6.50 per ton, while the 
feeding-value of the dry matter was nearly as 
great on the average as that in fine feeds, which 
averaged over $20 per ton; and furthermore, that 
the yield per acre of dry matter ranged from three 
to four and one-half tons. 
In these experiments the land was used, in many 
cases, for three crops, and in others for two; or, 
in other words, the soil was constantly occupied 
with growing crops. It is more than likely that 
the expense of growing these crops would be much 
greater in the East and South than in the richer 
lands of the Central West, because, in addition to 
the manures, it is usually necessary to apply com- 
mercial fertilizers in order to secure maximum 
crops. 
ROTATION SYSTEMS 
As already indicated, in soiling systems it is 
necessary, in order that the largest returns may 
be obtained and that a continuous supply of forage 
may be provided, to adopt systems of rotation 
that will result in the largest yield of food per 
acre. It is impossible to give rotations that are 
likely to be most useful for all conditions, as cli- 
mate, season, and adaptability of crop, vary widely 
