24 BULLETIN 994, U. S. DEPARTMENT OE AGRICULTURE. 
labor that has gone into the enterprise. The point is made that the 
going rate of wages paid to hired men is not a fair figure to cover 
the management and supervision given by the farm proprietor. In 
instances where hired managers are employed the total cost of 
then employment is distributed as a labor cost over the various 
enterprises, so that this question usually arises only with reference 
to the work of a proprietor. 
The position is taken by the Office of Farm Management and 
Farm Economics, and by most authorities, that the net returns 
from an enterprise or from the farm as a whole should pay for the 
supervision of the proprietor, and that the work he does should be 
counted as a charge at what such service could have been hired for. 
If a separate estimate of the value of the farmer's time is used as a 
supervisory charge, there is always a question as to the validity of 
the estimate made, and in some instances this estimate may distort 
the cost so that the results will be valueless for comparison. 
Fertility. — Not only have questions been raised as to the method 
of charging crops with the manure applied to them, and at the 
same time crediting it to the live stock responsible for its production, 
but the point has been made that in estimating the costs of producing 
crops an allowance should be made for the value of the fertility 
consumed in production, regardless of whether any fertilizer is applied. 
In instances where commercial fertilizer is used the practice has 
been to charge the first crop with all or a share of the actual cash cost, 
depending on the rate of availability of the fertilizer. In the case of 
farm manure the increase in returns due to the application of the 
manure is very difficult to estimate accurately, as the increase 
varies greatly with the kind of soil, the topography of the farm, 
the present yielding qualities of the land, the kind of manuje, the 
time of year applied, the rate of application, the manner of handling 
in the barnyard, and other factors that complicate the problem. 
It is apparent that an application of manure or fertilizer to a 
crop in one year provides a residue that is made available to succeed- 
ing crops through a term of years. In the case of barnyard manure 
it has been arbitrarily decided, where the farm is operated on a 
more or less definite rotation plan, to apportion the manure expense 
on the basis of either 50, 30, and 20 per cent over three years, or 
40, 30, 20, and 10 per cent over four years, depending somewhat 
upon the nature of the soil. In the case of commercial fertilizer, 
the more quickly acting fertilizers, such as nitrate of soda, are often 
charged as an annual expense, but lime and rock phosphate are 
usually charged over a four or five year period. More definite 
results from experimental work will probably give a more definite 
basis for this charge in the future than exists at the present time. 
