SILAGH RATIONS 29 
fact that many of the crops that are suitable for 
soiling belong to the legume family, which are 
relatively richer in nitrogenous substance than the 
cereals; and, because these legumes do not need 
nitrogenous manuring, they may be more cheaply 
raised than others. It frequently happens, also, 
that many of the cereal crops, when in a fit con- 
dition for soiling, are more highly nitrogenous 
than when approaching maturity; and a larger 
use of this nitrogenous food would probably be 
quite as economical as if smaller quantities were 
used and carbohydrates purchased. Hence, in 
soiling systems, the observation of those laws 
which are frequently very potent in regulating 
the cost of nutrients per unit of product when 
dried foods are exclusively used, may be in part 
ignored. 
A soiling system properly conducted requires a 
large number of crops, varying widely in their 
proportion of nitrogenous and non-nitrogenous 
nutrients. The land must be kept occupied; and a 
proper and self-sustaining rotation usually includes 
leguminous plants in order to maintain or increase 
the productiveness of the farm. If the feeder 
thinks that with every change of forage he would 
be required to change his feed ration, he might be 
deterred from adopting the system; but, as has 
already been pointed out, this change would not 
necessarily be required. 
