370 AGRICULTURAL ECONOMICS 



crop costs more than the market price, that the cost of oats is 

 ten cents greater than the price. What can the farmer do about 

 it? He can do a little figuring to see whether or not another 

 crop which requires his attention at the same periods and which 

 serves equally well as a nurse crop, barley for example, can be 

 substituted with a profit or with a smaller loss. If not, should 

 the farmer cut out the small grain crop? Usually not. The 

 total cost of man and horse labor would be reduced little by 

 omitting the oat crop, because oats and corn require labor at 

 different seasons and are supplementary to each other. If this 

 crop were not grown the hours of productive labor would prob- 

 ably be reduced and the average charge per hour for labor 

 applied to the corn would be greater. 



But this is not all. Oats are used as a nurse crop for clover, 

 and while it may be possible to grow clover without a nurse crop, 

 this would cost nearly as much as putting in the oats. Hence 

 the growing of small grain is usually the cheapest way to get 

 a seeding of clover, and where clover thrives this is the best way 

 to secure nitrogen for the corn crop. Thus it is the joint results 

 of the joint costs which are important. 



Having adopted a system of farming, the parts of it should 

 be adhered to so long as the system as a whole continues to be 

 attractive, and so long as each part of the system continues to 

 pay better than the substitute which is competing for a place in 

 the system. 



The corn, oats, and clover combination is not a complete sys- 

 tem of farming in itself. It is usually combined with one or 

 more live stock enterprises. Beef cattle and hogs, dairy cattle 

 and hogs, or straight dairying may be combined with this crop- 

 ping system. In each of these systems there are many instances 

 of joint costs. The joint cost of fattening steers and hogs is 

 commonly understood among feeders. Where butter fat and 

 pigs and veal calves are the products sold, these three products 

 have elements of joint cost. Where pure-bred cattle and milk 

 are sold the costs are joint and inseparable ; the important ques- 

 tion relates to the profit of the system as a whole. 



Where grade cows are purchased and used for the production 



